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'''Context-dependent memory''' is a [[psychology|psychological]] concept that refers to improved [[recall (memory)|recall]] of specific episodes or information when the [http://en.wiktionary.org/wiki/context ''context''] present at [[Encoding (memory)|encoding]] and [[recall (memory)|retrieval]] are similar. One particularly common example of context-dependence at work occurs when an individual has lost an item (e.g. lost car keys) in an unknown location. Typically, people try to systematically "retrace their steps" to determine all of the possible places where the item might be located. Based on the role that context plays in determining recall, it is not at all surprising that individuals often quite easily discover the lost item upon returning to the correct context.
'''Context-dependent Memory'''<br />
When contextual cues affect remembering, [[memory]] is said to be context dependent<ref name = "Smith, S. M. (1994)">Smith, S. M. (1994). Theoretical principles of context-dependent memory. In P. Morris & M. Gruneberg (Eds.),''Theoretical aspects of memory'' (2nd ed., pp. 168-195). London, England: Routledge. </ref>. Context-dependent memory implies that when events are represented in memory, contextual information is stored along with memory targets; the context can therefore cue memories containing that contextual information. It is important to note that in this case [[context]] refers to that which surrounds a target, whether the surrounding is spatial, temporal, or meaningful in nature. Experimental studies of the effects of context on various aspects of memory date back to at least experiments by [[Edward Carr]], who examined influences of incidental environmental manipulations on maze running in rats. Since that time, numerous studies of contextual effects on human memory have been published<ref> Smith, S. M. (1988). Environmental context-dependent memory. In G. M. Davies & D. M. Thomson (Eds.), ''Memory in context:
Context in memory'' (pp. 13-34). New York: Wiley.</ref>.


This example best describes the concept of context-dependent forgetting. However, the research literature on context-dependent memory describes a number of different types of contextual information that may affect recall such as environmental context-dependent memory, state-dependent memory, cognitive context-dependent memory and mood-congruent memory.<ref name = "BEA1">Baddeley, A., M. W. Eysenck, and M. C. Anderson. 2009. Memory. Psychology Press, New York, NY, US. </ref>. Research has also shown that context-dependence may play an important role in numerous situations, such as memory for studied material, or events that have occurred following the consumption of alcohol or drugs.
== Paradigms ==


==History==
=== Reinstatement ===
===Early Research===
[[Image:GandBStudy.jpg|thumb|right|Godden and Baddeley's 1975 Reinstatement Study.]] The most popular memory [[paradigm]] used has been that of reinstatement. Memory testing occurs either in the context in which the targets were experienced, or another target <ref name ="Smith, S. M. (1994)" />. Evidence of contextual cueing is then the finding that events are remembered better when the original context has been reinstated. Original studies used rats as subjects and found that if a rat [[learned]] to run a maze that was oriented in a particular way towards the overhead room lights, performance was better if the lighting arrangement was reinstated, rather than altered <ref>Carr, H. A. (1917). 'Maze studies with the white rat: I. Normal animals; II. Blind animals; III. Anosmic animals'. ''Journal of Animal Behavior, 7,'' 259-306. </ref>. Researchers had divers learn a list of words both on land and underwater and then subsequently recalled those words on land or underwater <ref>Godden, D. R. & Baddely, A. D. (1975).Context-dependent memory in two natural environments: on land and underwater. ''British Journal of Psychology, 66''(3), 325-331.</ref>. Being underwater was a good example of a natural environment that differed dramatically from that on land. Results demonstrated that what was learned underwater was best recalled underwater and what was learned on land was best recalled on land.
Psychologists have sought to understand the influence of contextual information on human memory for many years. Some of the earliest research on this topic was conducted by researchers in the 1930's who analyzed how changes in context affect an individual’s memory for [[nonsense syllable]]s.<ref name = "Pes1">Pessin, J. (1932). The effect of similar and dissimilar conditions upon learning and relearning. J. exp. Psychol. 15, 427-435.</ref> <ref name = "Far1"> Farnsworth, P.R. (1934). Examinations in familiar and unfamiliar surroundings. J. soc. Psychol. 5, 128-129.</ref> These early studies were unable to demonstrate an effect of context-dependent memory. Such [[statistical significance|non-significant]] results encouraged the development of new methods, such as a [[interference theory|retroactive interference]] paradigm, to analyze the effect of context on memory. By the 1950s, this technique was utilized to successfully demonstrate an effect of contextual information on memory recall.<ref name = "BS1">Bilodeau, I. M. & Schlosberg, H. (1951). Similarity in stimulating conditions as a variable in retroactive inhibition. J. exp. Psychol. 41, 119-204.</ref> However, the validity of using this particular paradigm has been questioned.<ref name = "S1">Strand, B.Z. (1970). Change of context and retroactive inhibition. J. verb. Learn. verb. Behav. 9 202-206.</ref> Indeed, much of the early literature on this topic failed to provide conclusive evidence of any context-dependent effects on memory.


By the end of the 1970's, numerous successful demonstrations of a context-dependent effect appear in the literature. As early as 1971, Jansen et al. found evidence that contradicted previous findings by demonstrating a context-dependent effect on memory for nonsense syllables.<ref name = "JHA1">Jansen, L.C., Harris, K. and Anderson, D. C. (1971). Retention following a change in ambient contextual stimuli for six age groups. Dev. Psychol. 4, 394-399.</ref> Further, in 1975, the question of whether contextual information influences memory recall was resolved following the publication of Godden and Baddeley’s seminal paper on the topic.<ref name = "GB1">Godden, D, & Baddeley, A. (1975). Context dependent memory in two natural environments. British Journal of Psychology, 66(3), 325-331.</ref> A few years prior to the publication of this study, researchers demonstrated that the memory of deep sea divers for events witnessed underwater was reduced after resurfacing.<ref name = "EWB1">Egstrom, G.G., Weltman, G., Baddeley, A.D., Cuccaro, W.J., and Willis, M.A. (1972). Underwater work performance and work tolerance. Report no. 51, Bio-Technology Laboratory, University of California, Los Angeles.</ref> The authors note in their 1975 paper that this incidental result immediately suggested a possible influence of the contextual environment (being underwater) on recall.<ref name = "GB1">Godden, D, & Baddeley, A. (1975). Context dependent memory in two natural environments. British Journal of Psychology, 66(3), 325-331.</ref> In order to test this hypothesis, Godden and Baddeley had divers learn and recall word lists in two separate environments; under water and on dry land. Their results demonstrated that memory for word lists learned under water was better when recall sessions occurred under water as well, and that a congruent effect existed for words learned and recalled on land. In simplified form: changing the context between encoding and retrieval reduced the divers’ ability to recall learned words. The publication of this study likely initiated the current synthesis of context-dependent memory as it is studied by psychologists today.<ref name = "BEA1"/>
=== Interference-Reduction ===
The interference paradigm uses a target list and an interfering list that are learned either in the same environment or in a different environment <ref name="Smith, S. M. (1994)" />. When interference effects are reduced because the lists are learned in different environments, this is taken as evidence of context-dependent memory. If contextual cues are associated with only the target list rather than with both the target and interfering lists, then the contextual information used in recall should cue fewer interfering memories. Context effects have been more robust with interference reduction than reinstatement paradigms.


===Theoretical background===
=== Multiple Input Context ===
In the Multiple Input Context paradigm a target set is studied repeatedly and tested with a free recall test <ref name ="Smith, S. M. (1994)" />. The study sessions are conducted either all within a single context or each in a different context. Recall is typically tested in a new unfamiliar context in all conditions. Material is recalled more accurately if the input contexts are varied rather than kept constant. This means that there is less association with the context of where the information is learned and there is little context-dependence, whereas if the study sessions are conducted in a single context there is much more context-dependence and since recall is tested in a new environment the context-dependence hinders recall.


A number of factors are thought to affect how contextual information interacts with memory recall. For example, a [[meta-analysis]] of the literature on environmental context-dependent memory by Smith and Vela<ref name = "SV1">Smith, S., and E. Vela. 2001. Environmental context-dependent memory: A review and meta-analysis. Psychon. Bull. Rev. (8) 203-220.</ref> has suggested that in cases where contextual information is not particularly salient, context-dependent effects on memory are reduced. Similarly, this meta-analysis suggests that reinstatement of context can be achieved not only by physically returning to the encoding environment, but also by mentally visualizing that environment. It should be noted that this study only considered environmental context-dependence.
== Types of Test ==
The type of memory test given to the subject is influential in determining whether or not contextual-dependent memory is found<ref name ="Smith, S. M. (1994)" />. The memory tests can vary in terms of the cues they provide, in terms of the number of cues, strength of the association of the cues targets, specificity, and a variety of other dimensions.


Additionally, other psychological constructs suggest further limits on how context can affect memory. For example, Johnson et al.’s Source Monitoring Framework proposes that the ability of an individual to remember the source of an episode will affect the likelihood of that memory being recalled.<ref name = "JHL1">Johnson, M.K., Hashtroudi, S., & Lindsay, D.S. (1993). Source Monitoring. Psychological Bulletin, 114 (1), 3-28.</ref> Hence, in the case of context-dependent memory, this Framework suggests that the effects of context on memory may also be limited by cognitive factors such as the ability of individuals to differentiate between individual contexts.
=== Outshining Principle ===
The '''Outshining Hypothesis''' states that tests that provide non-contextual cues, or that encourage subjects to generate such cues from memory, are the least likely to find context-dependence<ref name ="Smith, S. M. (1994)" />. Tests that encourage subjects to use non-contextual cues, even those generated imaginably from the subjects’ own memories, are less likely to find effects of contextual manipulations than tests that do not encourage the use of non-contextual cues.


==Neuroanatomy==
=== Context and Recognition Tests of Memory ===
[[File:Hippocampus.png|thumb|left|alt=Hippocampus|''The hippocampus is a brain structure which has been shown to be involved in context-dependent memory'']] There are a number of neuroanatomical structures that are thought to play a role in context-dependent memory which include [[File:Prefrontal cortex.png|thumb|right|alt=Prefrontal Cortex|''The prefrontal cortex is thought to play an important role in context-dependent memory'']] the [[hippocampus]] and [[prefrontal cortex]]. For example, [[functional magnetic resonance imaging]] (fMRI) has been used to demonstrate elevated activation in the hippocampus when contextual information matches from encoding to retrieval, suggesting that the hippocampus may be important in mediating context-dependent memory processes.<ref name = "wagner"> Wagner, A.D., Desmond, J.E., Glover, G.H., Gabrieli, J.D.E. (1998) Prefrontal cortex and recognition memory. Functional-MRI evidence for context-dependent retrieval processes. Brain 121:1985–2002</ref> Kalisch et al. provide further support for this role by demonstrating that context-dependent [[extinction]] memory is correlated with activation in both the hippocampus and ventromedial prefrontal cortex.<ref name = "kalischn">Kalisch et al. (2006) Context-Dependent Human Extinction Memory Is Mediated by a Ventromedial Prefrontal and Hippocampal Network. The Journal of Neuroscience, 26(37):9503-9511 </ref> Similarly, an experiment by Wagner et al. using fMRI demonstrated that activation of the right prefrontal cortex was dependent on contextual information.<ref name =wagn> Wagner, A.D., Desmond, J.E., Glover, G.H., & Gabrieli, J.D.E. (1998) Prefrontal cortex and recognition memory: Functional-MRI evidence for context-dependent retrieval processes. Brain, 121, 1985-2002. </ref> The authors of this study suggest that differential activation of the prefrontal cortex occurs because the different contexts require unique attempt processes for retrieval. In other words, depending on the retrieval context, participants used different strategies to recall information. Overall, the patterns of activation in the hippocampus and the prefrontal cortex following changes in contextual information suggest that these brain regions play an important role in context-dependent memory.
*The effect of context on memory has been far more inconsistent with [[recognition]] tests than [[recall]] tests and some investigations have found effects while others have not <ref>Hockley, W. E. (2008). The effects of environmental context on recognition memory and claims of remembering. ''Journal of Experimental Psychology, 34''(6), 1412-1429.</ref>.
<br><br><br><br>


==Environmental context-dependent memory==
*Early researchers suggested that item recognition is the degree to which information in the retrieval cue matches information stored in memory<ref>Murnane, K., & Phelps, M. P. (1995). Effects of changes in relative cue strength on context-dependent recognition. ''Journal of Experimental Psychology: Learning, Memory, and Cognition, 21'', 158–172.</ref>. Memory is activated in response to both the item information and the context information. A target presented in the same context at study and test would have a high degree of activation, because both item and context information would match the stored information. A target presented in a new context would have a lower degree of activation because only the item itself would match with information stored in memory; the nonmatching context would serve to decrease the overall [[familiarity]] value of the probe.
Environmental context-dependent memory, as defined by Smith, refers to a phenomenon whereby environmental context influences [[cognitive]] processing. <ref name ="Memoryincontext"></ref> As mentioned earlier, pioneering work on environmental context-dependent memory was performed by Godden and Baddeley in 1975. Their work looked at the memory recall of deep-sea divers on land and under water. Baddeley’s earlier research had indicated that the cold environment underwater could create a strong context dependency in deep sea divers. <ref name = "BEA1"></ref> They conducted an experiment where divers were placed under water or on the beach and listened to a prerecorded list of 36 unrelated, two-and-three syllable words.<ref name = "GB1"></ref> After listening to the list of words they were tested on their recall of the words either in the same environment they were tested in or in the alternative environment. <ref name = "BEA1"></ref> The results clearly showed that words learned underwater were best recalled underwater, and words learned on land were best recalled on land.<ref name = "GB1"></ref>
===Environmental reinstatement effect===
The most commonly researched area of environmental context-dependent memory is the phenomenon of the environmental reinstatement effect. This effect occurs when the reinstatement (i.e. revisiting) of an environmental context acts as a cue for past memories related to that particular environmental context. <ref name ="Memoryincontext">Smith, S.M. (1988) Environmental context-dependent memory. In G. Davies (Ed.), Memory in Context (pp. 13-31). John Wiley & Sons Ltd.</ref> Commonly, the memories that are recalled in this situation are those which were believed to be forgotten and it is only when an individual revisits this environmental context that these memories can be recalled. The degree to which this effect occurs varies depending on a number of factors, and may be classified under two types of reinstatement effects: long-term and short-term.


====Long-term reinstatement effects====
*More recently a dual-processing account of context effects in recognition memory was proposed. Subjects were asked to clarify recognition decisions as being made based on the [[recollection]] of specific details of a prior experience or on a strong sense of familiarity. The effects of context were only seen when the recognition was based on recollection<ref>Macken, W. J. (2002). Environmental context and recognition: The role of recollection and familiarity. ''Journal of Experimental Psychology: Learning, Memory, and Cognition, 28'', 153–161.</ref>.
The effects of environmental context-dependent memory are positively [[correlated]] with the length of time between initial [[encoding]] and [[retrieval]] of a memory, such that these effects increase with duration between encoding and retrieval. <ref name = "BEA1"></ref> This correlation may help to explain the "flood" of memories an individual experiences after returning to a previous residence or school following a long period of absence. <ref name = "BEA1"></ref> This common example of long-term reinstatement effects may occur for a number of reasons. For instance, a long duration of residence in a particular location is likely to increase the amount of environmental contextual information that is encoded to memory. When an individual moves to a new location with different contextual information, remembering and recalling information from this new environment may interfere with the old memories and result in "forgetting". However, when returning to the former location, the presence of contextual information "reactivates" these old memories, allowing them to be recalled, even after many years of absence. <ref name ="Memoryincontext"></ref>
<br><br>Another example of a long-term reinstatement effect is the revival of wartime memories by veterans and prisoners of war. Upon return to old battlefields, many of these individuals have been known to reconstruct tragic memories of life during wartime. Interestingly, a similar effect may occur when such individuals watch television war documentaries and broadcasts of battles, an affect attributed to [[generalization]] of the contextual cues associated with war <ref name ="Memoryincontext"></ref>. Importantly, due to the trauma associated with some of their experiences, recall of these past memories of war has been reported to lead many veterans to seek mental health care following exposure to this contextual information. <ref name ="Memoryincontext"></ref>


====Short-term reinstatement effects====
*Experiments have further examined the roles of recollection and familiarity in the effects of environmental context on recognition memory. Context was manipulated by presenting words in different screen colors and locations and by presenting words against real-world photographs. Overall hit and false-alarm rates were higher for tests presented in an old context compared to a new context. This effect was seen in both remember responses and estimates of familiarity. The results show that subjective feelings of recollection play a role in the effects of environmental context but are likely based more on a sense of familiarity that is evoked by the context than on explicit associations between targets and their study context.<ref>Smith, S. M. (1988). Environmental context-dependent memory. In G. M.
Momentary forgetting, such as forgetting what you wanted to get from the kitchen after getting up from your desk, is frequently experienced in day-to-day life. Usually what was forgotten can be remembered again by returning to the context where the event began.<ref name ="Memoryincontext"></ref> For example, imagine sitting at your desk and deciding you want to get a drink from the kitchen. Once you get to the kitchen, you completely forget what you wanted there. If you return to your desk, you will most likely remember what you wanted from the kitchen. <br><br>
Davies & D. M. Thompson (Eds.), ''Memory in context: Context in memory'' (pp. 13–34). New York: Wiley.</ref>
There is also evidence to support that our lives and memories may be compartmentalized by our environmental surroundings. Different environments, such as home, the work place, a restaurant or a theater, are associated with different memories and incidentally, different roles.<ref name ="Memoryincontext"></ref> This implies that surroundings cue memories, situations and even personal roles specific to the context a person is in at any given time.


===The Outshining Hypothesis===
=== Context and Implicit/Explicit Memory ===
The Outshining Hypothesis is based on the idea that a heavenly body is more difficult to see when it is obscured by a full moon. Similarly, incidental encoding of environmental context-dependent cues can be completely "outshone" when there are better cues available. However, these incidentally encoded environmental cues can be used to prompt memory recall if stronger cues are not present at encoding. A cue may be considered "better" simply because it has been more deeply processed, repeated more often, or has fewer items associated with it.<ref name ="Memoryincontext"></ref> As an example, a study by Steuck and Levy showed that environmental context-dependent memory has a decreased effect in word recall tests if the words are embedded into meaningful text.<ref name ="Memoryincontext"></ref> This is because meaningful texts are stored better in memory and are more deeply processed.
*The majority of research on context effects has been conducted using tests of [[explicit memory]]<ref name="Parker">Parkerm A., Dagnall, N., & Coyle, A. (2007). Environmental context effects in conceptual explicity/implicit memory. ''Memory, 15''(4), 423-434.</ref>.
*The investigation of context effects on [[implicit memory]] tests is more recent and unclear. Performance on implicit tests does not require retrieval from a particular study episode.
*Despite this some have suggested that context does play a role. However methodological problems limit these findings.
*When appropriate controls are taken only explicit test performance was reduced by context effects <ref name="Parker" />.


==State-dependent learning==
== Theoretical Principles ==
State-dependent learning refers to the finding that people recall more information when their physiological state is the same at encoding and retrieval.<ref name = "Pet1">Petersen, R.(1979) Scopolamine State-dependent memory processes in man. Psychopharmacology, 64, 309-314. </ref> For example, people that undergo alcohol intoxication while encoding information recall significantly more when they are also intoxicated during retrieval, compared to those whose alcoholic states differ from encoding to retrieval.<ref name = "Good1">Goodwin, D., Powell, B., Bremer, D., Hoine, H., & Stern, J. (1969) Alcohol and recall: state-dependent effects in man. Sciences, 163(3873), 1358-1360. </ref> This state-dependent learning effect has been shown in both human and animal research.<ref name = "Good1">Goodwin, D., Powell, B., Bremer, D., Hoine, H., & Stern, J. (1969) Alcohol and recall: state-dependent effects in man. Sciences, 163(3873), 1358-1360. </ref> ,<ref name=Nishi> Nishimura, M. Shiigi, Y, & Kaneto, H. (1990) State dependent and/or direct retrival by morphine in mice. Psychopharmacology, 100, 27-30. ,</ref> The state-dependent effect has also been generalized to a variety of drugs, including morphine,<ref name=Nishi> Nishimura, M. Shiigi, Y, & Kaneto, H. (1990) State dependent and/or direct retrival by morphine in mice. Psychopharmacology, 100, 27-30. ,</ref> cigarettes <ref name=Peters1> Peters, R., & McGee, R. (1982) Cigarette smoking and state-dependent memory. Psychopharmacology, 76, 232-235.</ref>, scopolamine,<ref name = "Pet1">Petersen, R.(1979) Scopolamine State-deoebdebt memory processes in man. Psychopharmacology, 64, 309-314. </ref> and nitric oxide <ref name = Mew> Mewaldt, S.P., Ghoneim, M.M, Choi, W.W., Kortilla, K., & Peterson, R.C. (1988) Nitrous Oxide and Human State-dependent memory. Pharmacology Biochemistry & Behavior, 30, 83-87. </ref>


=== Cue-Dependent Memory ===
Performance on memory tasks have been shown to be influenced by associated memory cues<ref name =
"Smith, S. M. (1994)" />. If contextual information is associated with target material, then contextual cues should stimulate memory for associated memory. By keeping memory searches within a delimited set, a set of information to be deliberately searched, then one’s retrieval efforts could be more efficient <ref>Smith, S. M., Glenberg, A.M. & Bjork, R.A. (1978). Environmental context and human memory. ''Memory and Cognition, 6'', 342-353.</ref>. Environmental contexts may cue memory by helping to delimit such a search set and therefore only memories with contextual associations are included. Although retrieval is of fundamental importance in free recall, it is not in recognition memory tasks, explaining why context-dependent memory does not impact recognition tests.


It is important to note, however, that certain drug states impair learning. For example, a study done by Rickles et al. demonstrated that despite the state-dependent effect associated with light marijuana use, people smoking marijuana showed slower learning than people in a placebo group.<ref name = "Rick1">Rickles, W., Cohen, M.J., Whitaker, C.A., & McIntyre, K.E.(1973) Marijuana induced state-dependent verbal learning </ref> More precisely, people who consumed marijuana during both the encoding and retrieval phases managed to learn the material in an average of 10 trials, whereas people who were in the [[placebo]] condition for both phases learned the same material in only 5.6 trials, on average.
=== Overshadowing ===
Not all information in the [[stimulus]] environment is necessarily [[encoded]] and stored in memory<ref name ="Smith, S. M. (1994)" />. A feature may not be stored when other more salient features are present in the environment because of a limited attentional capacity to encode and store features of stimuli. This explains why context effects are sometimes not observed. Inter-item associations occupy a subject’s attentional capacity, reducing the amount of [[attention]] that could be used to store contextual information.


===State as a contextual cue===
=== Contextual Fluctuation Theory ===
A tentative explanation for state-dependent recall is the use of the physiological state as a contextual cue. <ref name = Eich> Eich, J.M. (1980) The cue-dependent nature of state-dependent retrieval. Memory & Cognition, 157-173. </ref> Results of converging studies have shown that in tasks where no contextual cue is provided, internal states may serve as contextual cues. Therefore, people who are in a certain drug state at the time of encoding may utilize this state as a cue for retrieval. In contrast, when information is encoded and retrieved in different states, individuals have no [[sensory cue|cue]]s available to aid them in recalling information, leading to a decline performance. Eich provides further evidence for this theory, demonstrating that the introduction of additional contextual cues abolishes the state-dependent effect.<ref name = Eich /> If a cue such as a sound or an image is provided to remind people of what they encoded, they no longer require the state to prompt retrieval. In this instance, participants perform equally, regardless of the states at encoding and retrieval. According to Eich, the complete absence of any other observable reminders is critical for showing state-dependent cueing effects.
In a given stimulus environment, only a subset of the stimulus elements are conditioned on any learning trial <ref name ="Smith, S. M. (1994)" />. For example, if the word “MOUSE” were given as a to-be-learned target in a memory test, it would be encoded in several ways, such as a “small animal”, a “word that rhymes with house” or a “noun beginning with the letter m”. It was demonstrated that each target is encoded by an active encoding operator, and that the set of operators active at any given moment is smaller than the entire set of possible encoders <ref>Bower, G. H. (1972). Stimulus-samping theory of encoding variability, in A.W. Melton and E. Martin (eds).''Coding Processes in Human Memory,'' pp. 85-124, Washington, DC: Winston.</ref>. The active set of encoding operators was influenced by prevailing context.


==Cognitive context-dependent memory==
The '''Contextual Drift Hypothesis''' states in a lieu of systematic changes in context, there will be a gradual fluctuation of external events as well as internal mental events that increases contextual changes over time. Therefore, the probability that the same encoding operators active on two occasions decreases with greater time owing to greater contextual drift.
===Language of discourse===
Cognitive context-dependent memory is a term that describes improved memory recall for information that is both encoded and retrieved in the same cognitive state.<ref name = "BEA1"/> The clearest example of a cognitive context-dependent effect has been demonstrated in studies of proficient bilingual speakers, as it has been hypothesized that different languages provide a different cognitive context. It has been shown that both [[autobiographical]] and [[semantic]] memories could be better recalled when the same language was used for both encoding and retrieval. In particular, Marian and Neisser studied this effect in Russian immigrants to the United States by looking at autobiographical memory. <ref name = "MN1"> Marian, V., & Neisser, U. (2000). Language-dependent recall of autobiographical memories. Journal of Experimental Psychology: General, 129(3), 361-368.</ref> For this study, participants were asked to recall specific autobiographical memories in response to word cues. By varying both the language of the interview (either Russian or English) and the language in which word cues were presented, it was possible to alter which autobiographical memories were recalled. Importantly, interviewing and word-cueing in Russian biased participants towards recalling memories that had occurred in that language.


Matsumoto and Stanley found a similar effect for Japanese-American students. In particular, they demonstrated that cues words written in Japanese were more likely than English cue words to induce memories from participants’ past experiences in Japan.<ref name = "MS1">Matsumoto, A., & Stanny, C. (2006). Language-dependent access to autobiographical memory in japanese-english bilinguals and US monolinguals. Memory, 14(3), 378-390.</ref> Other studies have suggested similar results for bilinguals in Spanish and English<ref name = "SR1"> Schrauf, R. W., & Rubin, D. C. (2000). Internal languages of retrieval: The bilingual encoding of memories for the personal past. Memory and Cognition, 28(4), 616– 623.</ref>, and in Polish and Danish.<ref name = "LSF">Larsen, S., Schrauf, R. W., Fromholt, P., & Rubin, D. C. (2002). Inner speech and bilingual autobiographical memory: A Polish-Danish cross-cultural study. Memory, 10(1), 45 – 54.</ref> However, these studies used a different experimental design that does not demonstrate a causal effect. Additionally, Marian and Fausey found an effect of language on recall of semantic information in studies of Spanish-English bilinguals.<ref name = "MF1">Marian, V., & Fausey, C. M. (2006). Language-dependent memory in bilingual learning. Applied Cognitive Psychology, 20(8), 1025-1047. </ref> In particular, they show that accuracy and reaction times are improved for recall of academic information when the language of encoding and retrieval are similar. However, they also suggest that this effect is partially dependent on participants’ language proficiency (i.e. poor English speakers did not show an improvement in scores when English was used for both encoding and retrieval).
=== Component Level Theory ===
Componet level theory notes that environmental fluctuation is not random in most memory experimental contexts; faster changing cues are likely to be more specific than slower changing cues<ref name ="Smith, S. M. (1994)" />.
*The fastest changing cues are '''descriptive''' such as spelling or meaning.
*The next fastest cues are '''structural''' and represent the items categorical structure.
*The slowest changing components are '''contextual''' and are the most general because essentially all of the target traces contain the same contextual information.


=== Cue Overload ===
==="Motivational state"===
It has also been suggested that changes in “motivational state” between encoding and retrieval may affect memory recall for events. In a study by Woike et al.<ref name = "WLB1"> Woike, B. A., Lavezzary, E., & Barsky, J. (2001). The influence of implicit motives on memory processes. Journal of Personality and Social Psychology, 81, 935–945.</ref> participants were asked to read stories of differing motivational contexts and to recall specific information from these stories. The authors found that recall was biased towards stories containing information that matched participants’ own motivational state. Another study by Woike et al. provides a more direct examination of context-dependence by testing the effect of motivational contextual cues on recall of specific word pairs.<ref name = "WBB1"> Woike, B. A., Bender, M., & Besner, N. (2009). Implicit motivational states influence memory: Evidence for motive by state-dependent learning in personality. Journal of Research in Personality, 43(1), 39-48.</ref> Specifically, the authors demonstrated that associating word pairs with achievement cues produced a motivational context that increased memory for these word pairs. It should be noted that this study in particular uses neutral motivational cues as a control. These neutral cues did not produce similar improvements in recall for word pairs.
Context cues are the most overloaded, have more targets associated, and therefore are the weakest cues<ref name ="Smith, S. M. (1994)" />. Poorer recall has been found for list learning that occurs in a single context than when parts are learned in different contexts. The context cue in the single context condition is more overloaded than the cues in the multiple input context condition and is therefore a weaker cue.


==Mood-congruent and Mood-dependent memory==
=== Source Monitoring ===
One commonly reported phenomenon is that when individuals are in a "bad mood", they typically recall more bad things having happened to them and evaluate episodes in their lives in a more negative way than usual. It has been suggested that this effect occurs because a person’s mood at any given time has a strong influence on which aspects of their environment seem most salient. This affects what they remember about the past, and what they encode about the present <ref name = "Seventh Citation"> Lewis, P. & Critchley, H. (2003). Mood-dependent memory. Trends in Cognitive Sciences. </ref>. This particular effect is referred to as mood-congruent and mood-dependent memory.
Source Monitoring refers to determining the origin of one’s own remembered material and it can involve various types of decision processes related to attributions about memories<ref name ="Smith, S. M. (1994)" />. One important component of source monitoring is the retrieval of episodic contexts associated with or “bound to” remembered events<ref>Smith, S. M. & Vela, E. (2001). Environmental context-dependent memory: a review and meta-analysis. ''Psychonomic Bulletin & Review, 8''(2), 203-220.</ref>.These episodic contexts are retrieved to help the individual respecify the circumstances in which the remembered event has occurred. It is a process that helps distinguish among memories. Contextual information can benefit the retrieval of episodically associated events.


===Mood-congruent memory===
== Hippocampus and Context-Dependent Memory ==
Mood-congruent memory has been demonstrated by the finding that emotional material is remembered more reliably in moods that match the emotional content of these memories. <ref name = "Seventh Citation" /> For example, when feeling depressed, it is quite typical for an individual to remember more of the negative events in his/her past than of the positive events. Hence, the mood-congruence memory effect refers to better recall for information contained in experiences that match an individual’s current emotional state. This effect has been found to occur for both happy and sad memories. Specifically, happy people will remember more happy than sad information, whereas sad people will better remember sad than happy information. <ref name = "Eight Citation"> Mayer, D. McCormick, L. Strong. S. (1995). Mood-Congruent Memory and Natural Mood: New Evidence. Personality and Social Psychology Bulletin, 21(7), 736-746 </ref> Mood-congruent memory bias has been found for explicit but not implicit memory tasks,<ref name = "Ninth Citation"> Watkins, P.C., Vache, K., Vernay, S.P., & Muller, S. (1996). Unconscious mood-congruent memory bias in depression. Journal of Abnormal Psychology, 105, 34-41. </ref> which suggests that mood-congruent memory requires an awareness of one's own mood state. <ref name = "Tenth Citation"> Rothkopf, J. & Blaney, P. (1991) Mood congruent memory: The role of affective focus and gender. Cognition & Emotion, 5(1), 53-64.</ref> There also seems to be a higher occurrence of mood-congruent memory in females, possibly due to a purportedly greater amount of mood awareness. <ref name = "Tenth Citation" />
Further evidence for the existence of mood-congruent memory comes from studies demonstrating altered memory recall following experimentally-induced changes in mood using drugs.<ref name = "Eleventh Citation"> Klassen, T. Riedel, W.J. Deutz, N.E.P. & Van Praag, H.M (2002). Mood congruent memory bias induced by tryptophan depletion. Psychological Medicine, 32(1),167-172. </ref> Additionally, mood-congruent memory bias in explicit memory has been found to be specific to information congruent with negative moods rather than to all negative information. <ref name = "Twelfth Citation"> Watkins, P.C., Vache, K., Vernay, S.P., & Muller, S. (1996). Unconscious mood-congruent memory bias in depression. Journal of Abnormal Psychology, 105, 34-41.</ref> Studies of clinical depression have demonstrated congruent findings. <ref name = "Eight Citation" />


===Mood-dependent memory===
[[Image:hippocampus1.jpg|thumb|right|The Hippocampus (in green)]]In the 1970’s a theory about [[hippocampus]] function emerged from [[Pavlovian]] and instrumental learning which holds that the hippocampus is involved in processing the background ‘contextual’ information. Extensive literature on experimental [[brain]] [[lesions]] has accumulated demonstrating that the hippocampus is in fact involved in contextual processing. Hippocampal lesions impair conditioned fear responses to contextual stimuli and lesions render subjects insensitive to changes in context <ref name = "Smith, D. M. (2006)">Smith, D. M, & MIzumori, S. J. (2006). Hippocampal place cells, context, and episodic memory. ''Hippocampus, 16'', 716-729.</ref> The hippocampus generates a neural representation of the context, which can be transmitted to extrahippocampal brain regions to facilitate contextual modulation of behavioural responses and memories. Subjects were to distinguish two contexts that differed only in terms of behavioural requirements. Rats were trained to retrieve rewards from one location on a plus maze during the first half of each training session and from a different location in the same environment during the second half of the sessions. Learning to distinguish the two contexts was associated with the development of highly differential spatial firing patterns in rats given context training. The firing patterns of hippocampal [[neuronal]] populations were unique to each context and could therefore serve as a neuronal representation of the context.
Mood dependence is the facilitation of memory when mood at retrieval is matched to mood at encoding. <ref name = "Seventh Citation" /> Thus, the likelihood of recalling an event is higher when encoding and recall moods match than when they are mismatched. <ref name = "Thirtheenth Citation"> Eich, E. Macaulay, D. & Ryan, L. (1994) Mood dependent memory for events of the personal past. Journal of Experimental Psychology, 123(2), 201-215. </ref> However, it seems that only authentic moods have the power to produce these mood-dependent effects. <ref name = "Fourteenth Citation"> Eich, E. & Macaulay, D. (2000) Are real moods required to reveal mood-congruent and mood dependent memory? Psychological science, 11(3), 244-248.</ref> It has also been found that events which originate through internal mental operations such as reasoning, imagination and thought are more connected to one's current mood than are those that emanate from external sources—making the former less likely than external events to be recalled after a shift in mood state. <ref name = "Fifteenth Citation"> Eich, E. and Metcalfe, J. (1989). Mood-dependent memory for internal versus external events. Journal of Experimental Psychology, 15. 3. </ref> Importantly, this role of emotional state in memory recall suggests a potential mechanism for enhancing retrieval of past memories.


==Context-dependent forgetting==
*The idea that hippocampal lesions impair context processes is also well documented <ref name = "Smith, D. M. (2006)"/>. A [[GABA]]<sub>A</sub> [[agonist]], musimol, was used to temporarily inactivate the dorsal hippocampus before the training sessions. The loss of hippocampal processing was associated with a loss in behavioural flexibility.<br />
A large body of research has shown that memory performance is reduced when an individual’s environment differs from encoding to retrieval than if the two environments were the same. This effect is known as context-dependent forgetting. <ref name = "First Citation">Chu, S., Handley, V., & Cooper, S.R. (2003). Eliminating context-dependent forgetting: changing contexts can be as effective as reinstating them. The Psychological Record, 53, 549-559.</ref> As a result, a number of techniques have been created for the purpose of reducing context-dependent forgetting associated with environmental cues.


===Context recall technique===
A follow up study tested whether nonspatial, context-dependent memory retrieval required the hippocampus. Rats deprived of food or water were trained to enter one of three visually distinct goal boxes to obtain a [[reward]] <ref>Kennedy, P. M. & Shapiro, M. L. (2004). Retrieving memories via internal context requires the hippocampus. ''The Journal of Neuroscience, 24''(31), 6079-6085.</ref>. Two goal boxes were paired with either food or water, and a third box was never rewarded. To prevent rats from adopting a spatial response strategy, the goal boxes were moved among three locations at the start of each trial. In this manner, rats presented with identical external cues, including available [[visible]], [[auditory]], and [[olfactory]] stimuli, learned to approach and avoid equally reinforced goal objects depending on their current internal context. Rats were given complete lesions of either the [[fornix]] or the hippocampus. Contextual retrieval performance declined to near chance levels, but rats continued to avoid the unrewarded box and showed normal deprivation-based reward preference. The results demonstrate that the hippocampus is necessary for internally cued contextual retrieval of nonspatial memory.
One strategy for overcoming context-dependent forgetting is the context recall technique. This technique involves consciously generating old environmental cues from memory rather than physically reinstating the cued environment. <ref name = "Second Citation">Smith, S.M. (1984). A Comparison of two techniques for reducing context-dependent forgetting. Memory & Cognition, 12(5), 477-482.</ref> For example, if an individual learned material in a classroom in which the desks were organized in rows, that person could visualize that specific arrangement at a later testing date in a new environment (i.e. with the desks arranged in a circle). In a study conducted by Smith in 1979, participants who used this technique while being tested in a new room were able to recall as many words as participants who were tested in the original learning room <ref name = "Third Citation">Smith, S.M. (1979). Remembering in and out of context. Journal of Experimental Psychology: Human Learning and Memory, 4(5), 460-471.</ref>. Participants who were tested in a new room that did not use this technique showed typical context-dependent forgetting, recalling only two-thirds of the words recalled by the other groups. <ref name = "Second Citation" /> Therefore, the effects of context-dependent forgetting can reduced by visualization of the learning environment without full reinstatement.<ref name = "Third Citation" /> However, this technique is only useful and successful when the learning context is easy to remember. <ref name = "Second Citation" />


===Multiple learning context technique===
== Encoding Specificity Principle ==
The multiple-learning-context-technique is another strategy proposed by Smith to combat context-dependent forgetting. This technique involves presenting subsets of the learning material in multiple contexts rather than presenting them all in the same environment. <ref name = "Second Citation" /> When given a [[free recall]] test in a new room, participants who studied in multiple rooms recalled more words than participants who only studied in one room <ref name = "Second Citation" />. Smith suggests that when individuals have additional environmental cues their performance will be sustained because it will be less likely that all of the cues will be forgotten.
Encoding Specificity originated in experimental work by Thompson and [[Tulving]] designed to uncover effectiveness of [[retrieval]] [[cues]]<ref>Tulving, E., & Thomson, D. M. (1973). Encoding specificity and retrieval processes in episodic memory. ''Psychological Review, 80'', 352–373.</ref>. Specific encoding operations performed on what is perceived determine what is stored, and what is stored determines what retrieval cues are effective in providing access to what is stored. It was demonstrated that encoding of target words was influenced by an interaction between the perceptual input and its cognitive environment. [http://alicekim.ca/tulving.htm The Works of Endel Tulving]
<br />
There are four assumptions to be made:
# The ‘goodness’ of a particular encoding operation depends on the nature of the cues present at the time of retrieval.
# Effectiveness of a cue, with respect to a particular target item, depends on the conditions under which the target item was encoded.
# Successful recollection of an event depends on the compatibility between the trace and the cue.
# The compatibility relation between the trace and the cue, as a necessary condition of recollection of an event, is determined by specific encoding operations at the time of study and not by the properties of cues and target items, and their relations in semantic memory.


Along with the multiple learning context technique, other research has demonstrated that increasing the number of environmental cues will increase an individual's recall performance. <ref name = "Second Citation" /> The cue-overload theory proposed by Watkins and Watkins in 1975 explains that the effectiveness of an environmental cue will decline when there is an increase in the number of items that it is associated with. <ref>Watkins, M.J., & Watkins, O.G. (1976). Cue-overload theory and the method of interpolated attributes. Bulletin of the Psychonomic Society, 7(3), 289-291.</ref> Therefore, when given a fixed number of items to recall, performance will increase if the number of cues also increases. <ref name = "Second Citation" /> This theory focuses on one of the two factors that must be considered when determining the effectiveness of multiple learning environments: the variety of contextual cues. However, research conducted by Jones in 1976 demonstrates that in order for this technique to be useful, the cues must use different senses. <ref>Jones, G.V. (1979). Multirate forgetting. Journal of Experimental Psychology: Human Learning and Memory, 5(2), 98-114.</ref> For example, there is no recall advantage when only the number of visual cues is increased. On the other hand, there is a recall advantage when different sensory media such as sight, sound, and smell were added together. <ref name = "Fourth Citation">Parker, A., & Gellatly, A. (1997). Moveable cues: a practical method for reducing context-dependent forgetting. Applied Cognitive Psychology, 11, 163-173.</ref> Hence, this suggests that using multiple sensory media as sources for cues during encoding will provide an advantage in different testing environments where the number of contextual cues has been reduced.
A number of experiments have been directed at determining the generality of the conditions under which the encoding specificity principle can be demonstrated. Some have suggested that that the phenomena are general while others have led to conclusions that encoding specificity is limited <ref>Wiseman, S. & Tulving, E. (1976). Encoding specificity: relation between recall superiority and recognition failure. ''Journal of Experimental Psychology, 2''(4), 349-367.</ref>.Researchers analyzed the reasons for;
* '''recall superiority'''
* '''recognition failure'''
Results demonstrated that superiority of recognition over recall does not mean that all recallable words are recognized. Since recognition failure is obtained whether or not recall performance exceed recognition, the failure to find recall superiority does not demonstrate a limit to encoding specificity. Therefore recognition failure is dependent on the overall level of recognition but not on recall superiority.


===Attention===
== State-dependent Memory ==
The second factor to be considered when determining the effectiveness of multiple learning environments is the likelihood that an individual will even use environmental cues when recalling. Instructing subjects to use self-generated cues (i.e. the context recall technique) will increase recall for participants tested in a different environment. However, individuals do not automatically do this when learning occurs in a single location. <ref name = "Second Citation" /> Therefore, by moving individuals from room to room, they may pay more attention to the environmental cues. Smith claims that both the context recall technique and the multiple learning context technique work similarly, in that both methods force individuals to pay attention to and remember environmental information. <ref name = "Second Citation" />
State dependent memory differs from encoding specificity in that it depends upon manipulations of internal states as opposed to external stimuli <ref name ="Smith, S. M. (1994)" />. These internal states can include [[drug]]-induced (i.e. [[caffeine]]) or pharmacological states, as well as mood states. The theory states that one will remember more accurately when in the same physical state as they were when the information was encoded. Most state-dependent studies use a reinstatement paradigm and thus show that reinstatement of learning conditions optimize recall<ref name ="Smith, S. M. (1994)" />.


In 2003, Chu et al. demonstrated that conscious effort and attention is important to overcome context-dependent forgetting. Their research has shown that active processing of the context during the encoding phase is an important factor of successful performance. <ref name = "First Citation" /> When actively attending to environmental cues with the goal of using a technique such as the context recall technique, stronger associations are created between the material and the environment.<ref name = "First Citation" /> However, if an individual does not actively attend to environmental cues during the encoding phase, such cues may not be easily visualized in the recall phase if a new context is present.
=== Procedure of Tests and Results ===


===Ambient and transferable cues===
It is said that there are five factors that may play key roles in the occurrence of state-dependent effects in man: <ref>Eich, J. E. (1980). The cue-dependent nature of state-dependent retrieval. ''Memory and Cognition". 8 (2), 157-173. </ref>
The word [http://en.wiktionary.org/wiki/ambient ''ambient''] is defined as completely surrounding and encompassing.[[File: Orchestra.PNG|thumb|right|alt=Ambient and transferable cues|''Music is considered an ambient cue in that it is all encompassing and aids in recall when learning context and recall context are different'']] Some researchers have suggested that ambient cues, such as odour and sound, aid in recall when the learning context and recall context are different. <ref name = "Fourth Citation" /> In addition, these cues are useful in recall because they can also be transferable. For example, if music is played in a room in which material is learned, it is sometimes possible to transfer that musical source to a different room in which material will be tested. This phenomenon, which occurs when a memory or emotion is reactivated by a song that is associated to a specific event, demonstrates the effectiveness of sound (and odour) as useful cues in the absence of the original context.<ref name = "Fourth Citation" /> Using transferable cues may be useful for individuals who have difficulty using the context recall technique because they have trouble creating a mental image of the original environment. For example, this technique has been proven useful for patients at home who are trying to reproduce skills that they learned in a hospital environment <ref name = "Fourth Citation" />.
# The type of psychoactive drug administered
# The dosage of the drug dispensed
# The nature of the to-be-remembered items
# The "level" of item analysis
# The nature of retrieval cues available to the rememberer


==Context-dependent extinction==
When results are extrapolated from a state-dependent memory test that involves aspects of these five components, they are often deemed assymetrical. This term is used to indicate a specific configuration of results coming from an experimental design that has used two different states during the encoding and testing phases, 'drug' and '[[placebo]]'<ref name ="Smith, S. M. (1994)" />. An assymetrical result would mean that there was a [[main effect]] of drug and a state dependent [[interaction]] statistically. For example, if a substance impairs recall, yet has a state-dependent effect, the pattern of results is assymetric <ref name ="Smith, S. M. (1994)" />.
[[extinction (psychology)|Extinction]] refers to the loss of performance after a [[conditioned stimulus]] is no longer paired with an [[unconditioned stimulus]]. It can also refer to the loss of an [[operant conditioning |operant response]] when it is no longer reinforced.
Research done by Bouton (2002) has shown that extinction is not an example of unlearning, but a new type of learning where the performance of the individual is dependent on the context.<ref name= Bouton> Bouton, M.E. (2002) Context, ambiguity, and unlearning: sources of relapse after behavioral extinction. Biol. Psychiatry, 52, 976-986. </ref> The renewal effect is seen when a participant is first conditioned in a context (context A) and then shows extinction in another context (B). Returning to context A may renew the conditioned response. This evidence demonstrates that appropriate responses underlying extinction may be linked to contextual information.<ref name= Bouton> Bouton, M.E. (2002) Context, ambiguity, and unlearning: sources of relapse after behavioral extinction. Biol. Psychiatry, 52, 976-986. </ref> Hence, if a person is in the context in which he/she initially learned the material, that context is likely to cue this person to act as they were initially conditioned to act. If he/she is in the extinction context, then that context will likely prompt him/her not to respond.


=== Alcohol ===
===Clinical applications===
Extinction is often used in a type of clinical therapy called [[exposure therapy]] to treat disorders such as [[phobia]]s and [[anxiety]] and is also used to treat [[drug dependence]]. <ref name= Bouton> Bouton, M.E. (1988) Context and ambiguity in the extinction of emotional learning: implications for exposure therapy. Behaviour research & therapy, 26(2), 137-149. </ref> For example, if a person learns to associate snakes with a traumatic event such as being bitten, he or she may develop a phobia. As a treatment, a therapist may choose to expose the person to snakes in the absence of any traumatic event, leading to extinction of maladaptive behaviours related to fear. However, due to the fact that extinction is a context-dependent process, it may lead to relapse once the patient is no longer in the extinction context. <ref name= Bouton> Bouton, M.E. (2002) Context, ambiguity, and unlearning: sources of relapse after behavioral extinction. Biol. Psychiatry, 52, 976-986. </ref>
Testing the effect of drugs on memory began on [[animals]], not unlike many other psychological tests. Researchers found that animals tested in a "drugged" state remembered their training better if tested in a comparable drugged state as opposed to a non-drugged state. It was expected that animals would acquire learned responses better in a non-drugged state than when drugged<ref name = "Goodwin et. al (1969)">Goodwin, D. W., Powell, B., Bremer, D., Hoine, H., & Stern, J. (1969). Alcohol and Recall: State-Dependent Effects in Man. ''Science, 163,'' 1358-1360. </ref>. It was found, however, that that performance may actually improve in a drugged state, given that the original learning state was maintained<ref name = "Goodwin et. al (1969)" />.
In a study by Crombag and Shaham, rats were taught to self-administer a heroin and cocaine mixture followed by twenty days of extinction. Half of the rats experienced extinction in the same context as the original self-administration and the other half in a new context. The rats that underwent extinction in a new context renewed drug self-administration significantly more than the other rats when they were put back in the original context. <ref name=Crom> Crombag, H.S., & Shaham, Y. (2002) Renewal of drug seeking by contextual cues after prolonged extinction in rats. Behavioral Neuroscience, 116(1), 169-173. </ref>
A similar effect was shown in human exposure therapy for severe fear of spiders. The participants who were treated through extinction and later tested in the same context were significantly less afraid than the participants who were treated and tested in different contexts. This shows the lack of generalizability of one context to another in exposure therapy. <ref name=Min> Mineka, S., Mystkowski, J.L., Hladek, D., & Rodriguez, B.I. (1999) The effects of changing contexts on return of fear following exposure therapy for spider fear. Journal of Consulting and Clinical Psychology, 67(4), 599-604. </ref>
Hence, it should be taken into consideration that context-dependence of extinction is critical for successful treatments. In order to acquire stable and effective extinction of phobias, anxiety, or drug-seeking, the context of extinction must be as similar as possible to the day-to-day encounters with emotion-arousing cues that patients may experience.


==Tips for studying==
A breakthrough test pertaining to the effects of [[alcohol]] on human memory was conducted by Goodwin et al. in 1969. In this study, males were assigned randomly to one of four groups for a period of two days. Groups were either sober on both days, intoxicated on both days, or intoxicated for either day one or day two. Subjects were presented with a variety of skill-testing lessons and tasks for the duration of the study<ref name = "Goodwin et. al (1969)" />.


[[File:Studying.jpg|thumb|left|alt=student studying|''A student is suggested to prepare for an upcoming test by studying in a similar context as he or she is expected to be tested, for example, under silent conditions'']] According to the literature cited above, information is better recalled when the context matches from encoding to retrieval. Therefore, when a person is studying, he/she should match the studying context as best as possible to the testing context in order to optimize the amount of material that will be recalled. This idea was made apparent in a study done by Grant et al. <ref name=Grant> Grant, H.M., Bredahl, L.C., Clay, J., Ferrie, J., Groves, J.E., McDorman, T.A., Dark, V.J. (1998) Context-dependent memory for meaningful material: Information for students. Applied Cognitive Psychology, 12, 617-623.</ref> In this study, participants were asked to study meaningful information under either quiet or noisy conditions. Afterwards, they were asked short-answer and multiple choice questions on the previously learned material, which prompted both recognition and recall. Half of them were tested under silent conditions and the other half under noisy conditions. The participants whose noise-level matched during studying and testing conditions remembered significantly more information than those whose noise-level was mismatched. Grant et al. conclude that students should take into consideration the context of testing, such as the noise level, while studying in order to maximize their performance on both recall and recognition tasks.
===== Results =====
It was found that in tasks involving recall interference, learning transfer was better when the subject was intoxicated on both days (learning session and testing session) than when they were intoxicated during the learning session alone. However, with regards to tasks pertaining to recognition in specific, learning transfer was not significantly affected by the changes in internal states. Therefore, it is proven that alcohol had a state-dependent effect on men, but it does not affect all forms of human memory<ref name = "Goodwin et. al (1969)" />.
Further, in cases where it is not possible to have similar learning and testing contexts, individuals who pay conscious attention to cues in the learning environment may produce better results when recalling this information. By doing so, individuals are better able to create a mental image of the original context when trying to recall information in the new testing context—allowing for improved memory retrieval. <ref name = "Second Citation">Smith, S.M. (1984). A Comparison of two techniques for reducing context-dependent forgetting. Memory & Cognition, 12(5), 477-482.</ref> Further, several contextual cues should be attended to, using more than one sensory system, in order to maximize the number of cues that can help in remembering information. <ref name = "Second Citation" />

<br>
=== Nicotine ===
==References==
After the effects of alcohol on memory were investigated, Roger Peters and Rob McGee pioneered a landmark study developed to test the effects of [[nicotine]] on memory in humans in 1982. Volunteers who had smoked more than 12 [[cigarettes]] a day for the previous two years were chosen to participate. Subject's were asked not to smoke for 9 hours prior to the experiment and were assigned to groups (high, low and no nicotine intake) at random, upon arrival. Subjects were not aware of what group they were assigned to. They were then asked to smoke at their own pace, and rate their stress level afterwards (ex. "I feel rested.", "I feel upset", etc.). Later on, the subjects were tested on performance during several forms of memory tasks <ref name = "Peters et. al )1982)">Peters, R., & McGee, R. (1982). Cigarette Smoking and State-Dependent Memory. ''Psychopharmacology, 76,'' 232-235. </ref>.

===== Results =====
It was found that subjects performed better on recall tests when they were in the same state as they had been when the information was first encoded. In addition, the observed state-dependent memory effect on memory was due to the [[physiological arousal]] that came about as a product of the nicotine content of the cigarette <ref name = "Peters et. al )1982)" />.

=== Marijuana ===
The effects of [[marijuana]] on memory were tested by Eich, Weingartner, Stillman and Gillin in 1975. For their two-day study, subjects were divided into two groups at random upon their arrival. On day one of the experiment, subjects in one group smoked cigarettes containing [[tetrahydrocannabinol]] (also known as THC - the active ingredient in marijuana), or not (placebo condition). The subjects then underwent an encoding process which involved learning a series of words. On day two, half of the subjects smoked a THC cigarette, and the other half smoked herbal (placebo) cigarettes before engaging in both free-recall and cued-recall tests.<ref name = "Eich et. al (1975)">Eich, J. E., Weingartner, H., Stillman, R. C., & Gillin, J. C. (1975). State-dependent accessibility of retrieval cues in the retention of a categorized list ''Journal of Verbal Learning and Verbal Behavior, 14,'' 408-417. </ref>.

===== Results =====
This study proved that participants who smoked the cigarettes during both the encoding and retrieval processes did better than those participants who smoked the cigarettes containing [[THC]] in either the encoding or the retrieval process and not in the other. It is important to note however, that participants in the placebo-placebo condition did better overall than participants in the THC-THC condition <ref name = "Eich et. al (1975)" />.

== Transfer Appropriate Memory ==

Transfer appropriate processing is the [[phenomenon]] that demonstrates that the memory performance is also influenced by the relationship between how information is encoded and how the information is then retrieved. Transfer appropriate processing suggests that the more similar the context of encoding and retrieval processes are, more information will be remembered. Transfer appropriate processing was originally proposed as a principle of memory processing relations between encoding and retrieval <ref name = "Morris et al 1977"> Morris D. C., Bransford J. D., Franks J. J. (1977) Levels of Processing Versus Transfer Appropriate Processing. ''Journal of verbal learning and verbal behavior,21'', 519-533 </ref>. With this, transfer appropriate processing is seen as a complement to the encoding specificity principle <ref name = "Hornberg et al 2004" > Hornberg M., Morcom A. M., Rugg M. D. (2004) Neural correlates of retrieval orientation: effect of study-test similarity. ''Journal of Cognitive Neuroscience, 16,'' 3962-3972. </ref>.



This phenomenon has plenty of support; it was found that when you learn words by looking at their meaning you are best at remembering them while being tested on their meaning as compared to being tested on their phonetics. Conversely it was found that if you learn words through rhyming, you are best at remembering when being tested on their phonetics, whereas the performance declines when being tested for its meaning. <ref name = "Morris et al 1977" /> This also holds true when looking at pictures versus words. <ref name = "Hornberg et al 2004" />



=== Transfer Appropriate Processing and Prospective Memory ===


Transfer appropriate processing was developed to help explain [[retrospective memory]], but it has also been shown to help explain [[prospective memory]]. The two types of memory differ in that prospective memory deals with everyday things, like remembering to go to the grocery store after work, and retrospective is more like having to write a test about things you have learned in class. The main difference involves cue recognition, in retrospective memory there is an awareness of the cues and some form of direction with how to use them, whereas prospective memory involves no cue aid, it typically deals with having to know when to recognize the cues needed to remember the information. Transfer appropriate processing has been shown to hold true about prospective memory so long as during the learning process the individual is aware of and learns the cues <ref> Meier B., Graf P. (2000) Transfer appropriate processing for prospective memory tests. ''Applied Cognitive Psychology, 14,'' S11-S27 </ref>.

=== Transfer Appropriate Processing and functional Magnetic Resonance Imaging (fMRI) ===

When looking at a brain imaging using fMRI, there is greater activation in the brain when the testing phase matches the learning phase. If people learned information by looking at images, there was greater activation if they were tested with pictures as opposed to being tested by words, and the same phenomenon was shown when people learned words and were tested with words as opposed to pictures <ref> Park H., Rugg M. D. (2008) The relationship between study processing and the effects of cue congruency at retrieval: fMRI support for transfer appropriate processing. ''Cerebral Cortex, 18,'' 868-875. </ref>.

== Mood-Congruent Memory ==
Refers to contexts that are internal to a person. <br />Emotional material is preferentially processed in [[mood]] states with a matching affective valence <ref>Blaney, P. H. (1986). Affect and memory: a review. ''Psychological Bulletin, 99'', 229-246.</ref>.For example, a happy mood makes it easier to recall memories of positive occurrences or information with positive connotations, while negative memories predominate in negative moods <ref>Lewis, P.A., Critchley, H. D., Smith, A.P, & Dolan, R.J. (2004). Brain mechanisms for mood congruent memory facilitation. ''NeuroImage, 25'', 1214-1223.</ref>.Mood congruent memory is said to occur when mood-congruent material is learned and recalled better than mood incongruent memory<ref>Mayer, J.D., McCormick, L. J., & Strong, S. E. (1995). Mood congruent memory and natural mood: new evidence. ''Personality and Social Psychology, 21''(7), 736-746.</ref>.
<br />
It may be related to another effect, mood-congruent judgment. The mood-congruent judgment effect states that mood-congruent material will be judged as possessing “greater merit” in many ways. For example, a happy person will judge positive events as more likely than negative events. The two effects are related.

Because mood is a complex concept, any one of several operations may be employed to study it:

*Moods may be experimentally induced, which permits random assignment of moods. This method however may fail to create an ecologically valid version.
*[[Psychopathological]] moods may be studied but may be confounded with mental illnesses.
*Natural everyday moods may be surveyed.

Most laboratory mood studies begin with manipulating a participant’s mood to make them happy or sad, and then measure the person’s memory for happy and sad experimental material. [[Gordon H. Bower]] did just this in his 1981 study on the effects of mood on memory. He found that when subjects learned information in a happy state, their percentage of recall was much better when tested in a happy state (moreso than a sad or neutral state). The same effect was found when subjects were in a sad state when information was encoded; their percentage of recall was much better when tested in a sad state as opposed to happy or neutral.<ref>Bower, G. H. (1981).Mood and Memory. ''American Psychologist''. 36, 129-148.</ref>. This proves that similarity of state has a significant effect on performance.

Using natural-mood and experimental approaches provide more valid evidence however have often failed to find the effect. Recently researchers proposed to test natural mood and succeeded in finding mood-congruent memory with natural mood because of inaccuracies of previous studies.

=== Processes that Mediate Mood Congruent Memory ===
*The first possibility is that mood-congruence is directly produced by changes in arousal associated with the presence of an emotional state, either a prevailing mood or one produced by experimental procedures<ref>Varner, L. J. & Ellis, H. C. (1998). Cogntive activity and physiological arousal: processes that mediate mood-congruent memory. ''Memory & Cognition'', 26(5), 939-950.</ref>.
*The second possibility is that mood congruence is a result of cognitive processes activated as a consequence of the emotional state experienced and not physiological arousal. This is the dominant model.

Findings of two experiments support the proposal that cognitive activity mediates the mood congruence phenomenon. The findings provide a picture of how an emotional state leads to the selective processing of different types of information based on content. Mood congruence can be understood in terms of the cognitive activity that occurs at the time of the processing of information and not one’s state of arousal.

=== Brain mechanisms for Mood-congruent memory ===
Recently researchers have addressed the neural processes mediating mood congruent effects in memory by using [[functional magnetic resonance imaging]] (fMRI)<ref name = "Mayer, J. D. (1995)">Mayer, J. D., McCormick, L. J., & Strong, S. E. (1995). Mood-congruent memory and natural mood: new evidence. ''Personality and Social Psychology Bulletin, 21''(7), 736-746.</ref>. One dominant model of emotional context states that memories are stored as distributed [[traces]], with different [[nodes]] in the trace network representing different aspects of the memory (i.e. the place where it happened, the sounds or smells present, and the emotional valence of the memory). The emotional nodes can be excited by a wide range of stimuli with the appropriate valence. Once they are active they can propagate excitation to the rest of the associated [[network]], bringing the whole trace nearer to the threshold of excitation required for retrieval and thus facilitating recall.

The theory was tested and results showed that the subgenule cingulate and posteriolateral orbitofronal cortex demonstrated shared activity across both encoding and retrieval contrasts. The results are in line with the predictions of the associative memory hypothesis, however further studies will be required to determine whether or not these activities are in fact associated with facilitation <ref name = "Mayer, J. D. (1995)"/>.

Another experiment used event-related fMRI to index neural activity during the retrieval of emotional and non-emotional contextual information<ref>Maratos, E. J., Dolan, R. J., Morris, S. J., Henson, R. N. A. & Rugg, M. D. (2001). Neural activity associated with episodic memory for emotional context. ''Neuropsychogiaq, 39'', 910-920.</ref>. Recognition of words presented in emotionally negative relative to emotionally neutral contexts was associated with enhanced activity in right dosolateral prefrontal cortex, left [[amygdala]] and hippocampus, right lingual gyrus and posterior cingulated cortex. Recognition of words from positive relative to neutral contexts were associated with increased activity in bilateral prefrontal and orbitofrontal cortices, and left anterior temporal lobe. There was enhancement of activity in networks supporting episodic retrieval of information. Also regions known to be activated when emotional information is encountered in the environment are also active when emotional information is retrieved from memory.

== Colour and Context-Dependent Memory ==

A [[meta-analysis]] has demonstrated the [[reliability]] of context-dependent memory, however for theoretical reasons has excluded such contexts as background [[colour]], [[voice]], [[posture]], and [[odor]] <ref>Isarida, T, & Isarida, T. K. (2007). Environmental context effects of background colour in free recall. ''Memory and Cognition, 35''(7), 1620-1629.</ref>.

Early studies found no context effect for sentence recall when the to-be-remembered (TBR) items were printed on different coloured sheets of paper <ref>Pointer, S. C. & Bond, N. W. (1998). Context-dependent memory: Colour versus odour. ''Chemical Senses, 23'', 359-362.</ref>.

Recently, it was reported that background-colour effects in recognition discrimination appeared when six background colours were used but disappeared when two background colours were used. In these studies, background colours changed item-by-item in both conditions however the two colour condition was more likely to be cue overloaded. However, it was still unknown whether the background colour context effect was exclusively determined by cue overload. In order to solve this question, undergraduate students studied words presented one by one against a background colour, and oral free recall was tested. Significant context effects were found in which two background colours were randomly alternated word by word. However, context effects were not found when a common background colour was presented for all items. The results indicate that a change in background colours is necessary and sufficient to produce context effects. At the time of encoding, an item-by-item change in background colour is necessary for producing context effects, whereas the other environmental contexts can produce context effects with the total list of items.

This functional difference may relate to a difference in the generality of contextual association. Contexts can be classified in terms of their associative generality. One type of context can associate with a limited number of elements of an event because it changes relatively quickly, and is called '''local context'''. Another type of context can associate with all elements of an event because it remains stable or changes very slowly during the event, and is called '''global context'''.

== Context and Individual Differences ==
Individuals may be differential to environmental context-dependent effects<ref name ="Smith, S. M. (1994)" />. Individuals may differ in terms of encoding the environmental context information, retrieving it from memory, and performing other processes which affect context-dependent memory. One possibility is field dependence/independence. Field dependence is considered to be one aspect of a more general personality factor defined by a holistic (field-dependent) versus an analytical (field-independent) orientation to the world. Field-dependent subjects are less able than field-independent ones to avoid contextual influences in making perceptual judgements; that is, they are more affected by perceptual contexts. It may also be the case that field-dependent subjects are more affected by learning and memory contexts than field-independent subjects. More research is needed to clarify this hypothesis.

== Stress and Context-dependent Memory ==
The brain structures underlying contextual influences on memory are susceptible to stress <ref>Schwabe, L., Bohringer, A., & Wolf, O. T. (2008). Stress disrupts context-dependent memory. ''Learning and Memory, 16,'' 110-113.</ref>.<br /> Healthy adults were exposed to either a stressful condition or a control condition before they learned an object-location task in a room that was scented with vanilla. The subject's memory was tested one day later in either the same room or in a different context. Stress prior to the encoding abolished the context-dependent memory enhancement that was displayed in the control group. These findings represent the first implications of impaired context-dependent memory following stress.

== Practical Applications ==

=== Context and Application in the classroom ===
Whether or not classroom exam scores suffer as a function of the testing environment (e.g. testing in the same classroom versus an unfamiliar environment) is an educational concern<ref name ="Smith, S. M. (1994)" />. If environmental changes lead to poorer test scores, it is not only a concern of the student, but also to educators. As a student, one may think it is better to study in the same room where you will take the exam. However it has been shown that this is applying context-dependent memory in a less than optimal way. If something is learned in many different contexts, and one studies in many different places, then the information becomes context-independent. One can use knowledge when needed, rather than having to be in the same place.

The classroom provides a more typical non-laboratory situation for observing the occurrence or the nonoccurance of context-dependent memory than previous nonlaboratory situations used such as being underwater vs. on land <ref>Saufley, W. H., Otaka, S. R., & Bavaresco, J. L. (1985). Context effects: classroom tests and context independence. ''Memory & Cognition, 13''(6), 522-528.</ref>. One study reported an absence of contextual dependence in the college/university classroom, concluding that there are limits to the influence of contextual associations. One possibility is that unlike tests that have previously shown context dependence, Godden and Baddely's study underwater, college/university exams are not exclusively tests of rote memory. These classes have other characteristics that could account for the lack of influence of contextual associations and even make the classroom an inappropriate environment for testing context-dependent memory. Therefore, there is no evidence that in a natural environment a change in the classroom context affects test performance.

=== Eyewitness Testimony ===
[[Eyewitness testimony]] may or may not be enhanced by returning the eyewitness to the scene of the witnessed event<ref name =
"Smith, S. M. (1994)" />. The efficiency of context reinstatement procedures for improving eyewitness memory accuracy is an important issue for criminal investigators. Researchers had unexpected events staged before numerous eyewitnesses<ref>Smith, S. M., & Vela, E. (1992). Environmental context-dependent eyewitness recognition. ''Applied Cognitive Psychology, 6'', 125-139.</ref>. The participant's ability to identify the person committing the crime was tested using a photo lineup. The hypothesis was supported and physical reinstatement of the environmental context of a live scene improves eyewitness testimony of a person seen at the event. One reason is that the recognition of faces may be more likely than words to be context-dependent.

The [[Cognitive interview]] (CI) has been developed in response to improve communication during an interview with an eyewitness <ref>Memon, A., Wark, L., Bull, R., & Koehnken, G. (1997). Isolating the effects of the cognitive interview techniques. ''British Journal of Psychology, 88''(2), 179- 198. </ref>. One of four components that are used is the mental reinstatement of the physical and personal contexts that existed at the time.

Contextual reinstatement appears to be an effective method for improving eyewitness recognition, but more extensive research in this area will be needed to improve the effectiveness of these memory-enhancement techniques.

=== Memory in Clinical Therapy ===
Another application area that that could be affected by environmental context-dependent memory<ref name ="Smith, S. M. (1994)" />. Clinical populations may differ in the way context information tends to be encoded. One possibility is that individuals with [[depression]] have a greater tendency than nondepressed individuals to integrate information associated with their emotional state with information in ongoing events. If this is the case, stored ensembles (context and item information) that incorporate information regarding a depressed emotional state may lead to a greater tendency to recognize future events as depressing. This finding is based on the ICE theory of context-dependent recognition memory.

=== Memory and Aging ===
One method for alleviating memory deficits due to age could be used to use environmental support<ref name ="Smith, S. M. (1994)" />. That is, to use specially designed environments that provide the elderly with physical cues that serve as memory aids.

It has been well established that older adults do not perform as well as younger adults on many standard [[episodic memory]] tests <ref>Murnane, K., Phelps, M. P., & Malmberg, K. (1999). Context-dependent recognition memory: the ICE theory. ''Journal of Eperimental Psychology, 128''(4), 403-415.</ref>. This difference might, in part, be caused by differences in context encoding between the two age groups. However, as with results of context-dependent recognition tests, the findings have been ambiguous. Some researchers have found no differences in context effects between the young and the elderly, whereas other have found impairments in context processing among the elderly compared to younger adults.

== References ==


{{reflist}}
<references/>


{{memory}}
== External Links ==


[[Category:Memory processes]]
[http://alicekim.ca/tulving.htm The Works of Endel Tulving]

Revision as of 20:23, 24 March 2010

Context-dependent memory is a psychological concept that refers to improved recall of specific episodes or information when the context present at encoding and retrieval are similar. One particularly common example of context-dependence at work occurs when an individual has lost an item (e.g. lost car keys) in an unknown location. Typically, people try to systematically "retrace their steps" to determine all of the possible places where the item might be located. Based on the role that context plays in determining recall, it is not at all surprising that individuals often quite easily discover the lost item upon returning to the correct context.

This example best describes the concept of context-dependent forgetting. However, the research literature on context-dependent memory describes a number of different types of contextual information that may affect recall such as environmental context-dependent memory, state-dependent memory, cognitive context-dependent memory and mood-congruent memory.[1]. Research has also shown that context-dependence may play an important role in numerous situations, such as memory for studied material, or events that have occurred following the consumption of alcohol or drugs.

History

Early Research

Psychologists have sought to understand the influence of contextual information on human memory for many years. Some of the earliest research on this topic was conducted by researchers in the 1930's who analyzed how changes in context affect an individual’s memory for nonsense syllables.[2] [3] These early studies were unable to demonstrate an effect of context-dependent memory. Such non-significant results encouraged the development of new methods, such as a retroactive interference paradigm, to analyze the effect of context on memory. By the 1950s, this technique was utilized to successfully demonstrate an effect of contextual information on memory recall.[4] However, the validity of using this particular paradigm has been questioned.[5] Indeed, much of the early literature on this topic failed to provide conclusive evidence of any context-dependent effects on memory.

By the end of the 1970's, numerous successful demonstrations of a context-dependent effect appear in the literature. As early as 1971, Jansen et al. found evidence that contradicted previous findings by demonstrating a context-dependent effect on memory for nonsense syllables.[6] Further, in 1975, the question of whether contextual information influences memory recall was resolved following the publication of Godden and Baddeley’s seminal paper on the topic.[7] A few years prior to the publication of this study, researchers demonstrated that the memory of deep sea divers for events witnessed underwater was reduced after resurfacing.[8] The authors note in their 1975 paper that this incidental result immediately suggested a possible influence of the contextual environment (being underwater) on recall.[7] In order to test this hypothesis, Godden and Baddeley had divers learn and recall word lists in two separate environments; under water and on dry land. Their results demonstrated that memory for word lists learned under water was better when recall sessions occurred under water as well, and that a congruent effect existed for words learned and recalled on land. In simplified form: changing the context between encoding and retrieval reduced the divers’ ability to recall learned words. The publication of this study likely initiated the current synthesis of context-dependent memory as it is studied by psychologists today.[1]

Theoretical background

A number of factors are thought to affect how contextual information interacts with memory recall. For example, a meta-analysis of the literature on environmental context-dependent memory by Smith and Vela[9] has suggested that in cases where contextual information is not particularly salient, context-dependent effects on memory are reduced. Similarly, this meta-analysis suggests that reinstatement of context can be achieved not only by physically returning to the encoding environment, but also by mentally visualizing that environment. It should be noted that this study only considered environmental context-dependence.

Additionally, other psychological constructs suggest further limits on how context can affect memory. For example, Johnson et al.’s Source Monitoring Framework proposes that the ability of an individual to remember the source of an episode will affect the likelihood of that memory being recalled.[10] Hence, in the case of context-dependent memory, this Framework suggests that the effects of context on memory may also be limited by cognitive factors such as the ability of individuals to differentiate between individual contexts.

Neuroanatomy

Hippocampus
The hippocampus is a brain structure which has been shown to be involved in context-dependent memory

There are a number of neuroanatomical structures that are thought to play a role in context-dependent memory which include

Prefrontal Cortex
The prefrontal cortex is thought to play an important role in context-dependent memory

the hippocampus and prefrontal cortex. For example, functional magnetic resonance imaging (fMRI) has been used to demonstrate elevated activation in the hippocampus when contextual information matches from encoding to retrieval, suggesting that the hippocampus may be important in mediating context-dependent memory processes.[11] Kalisch et al. provide further support for this role by demonstrating that context-dependent extinction memory is correlated with activation in both the hippocampus and ventromedial prefrontal cortex.[12] Similarly, an experiment by Wagner et al. using fMRI demonstrated that activation of the right prefrontal cortex was dependent on contextual information.[13] The authors of this study suggest that differential activation of the prefrontal cortex occurs because the different contexts require unique attempt processes for retrieval. In other words, depending on the retrieval context, participants used different strategies to recall information. Overall, the patterns of activation in the hippocampus and the prefrontal cortex following changes in contextual information suggest that these brain regions play an important role in context-dependent memory.





Environmental context-dependent memory

Environmental context-dependent memory, as defined by Smith, refers to a phenomenon whereby environmental context influences cognitive processing. [14] As mentioned earlier, pioneering work on environmental context-dependent memory was performed by Godden and Baddeley in 1975. Their work looked at the memory recall of deep-sea divers on land and under water. Baddeley’s earlier research had indicated that the cold environment underwater could create a strong context dependency in deep sea divers. [1] They conducted an experiment where divers were placed under water or on the beach and listened to a prerecorded list of 36 unrelated, two-and-three syllable words.[7] After listening to the list of words they were tested on their recall of the words either in the same environment they were tested in or in the alternative environment. [1] The results clearly showed that words learned underwater were best recalled underwater, and words learned on land were best recalled on land.[7]

Environmental reinstatement effect

The most commonly researched area of environmental context-dependent memory is the phenomenon of the environmental reinstatement effect. This effect occurs when the reinstatement (i.e. revisiting) of an environmental context acts as a cue for past memories related to that particular environmental context. [14] Commonly, the memories that are recalled in this situation are those which were believed to be forgotten and it is only when an individual revisits this environmental context that these memories can be recalled. The degree to which this effect occurs varies depending on a number of factors, and may be classified under two types of reinstatement effects: long-term and short-term.

Long-term reinstatement effects

The effects of environmental context-dependent memory are positively correlated with the length of time between initial encoding and retrieval of a memory, such that these effects increase with duration between encoding and retrieval. [1] This correlation may help to explain the "flood" of memories an individual experiences after returning to a previous residence or school following a long period of absence. [1] This common example of long-term reinstatement effects may occur for a number of reasons. For instance, a long duration of residence in a particular location is likely to increase the amount of environmental contextual information that is encoded to memory. When an individual moves to a new location with different contextual information, remembering and recalling information from this new environment may interfere with the old memories and result in "forgetting". However, when returning to the former location, the presence of contextual information "reactivates" these old memories, allowing them to be recalled, even after many years of absence. [14]

Another example of a long-term reinstatement effect is the revival of wartime memories by veterans and prisoners of war. Upon return to old battlefields, many of these individuals have been known to reconstruct tragic memories of life during wartime. Interestingly, a similar effect may occur when such individuals watch television war documentaries and broadcasts of battles, an affect attributed to generalization of the contextual cues associated with war [14]. Importantly, due to the trauma associated with some of their experiences, recall of these past memories of war has been reported to lead many veterans to seek mental health care following exposure to this contextual information. [14]

Short-term reinstatement effects

Momentary forgetting, such as forgetting what you wanted to get from the kitchen after getting up from your desk, is frequently experienced in day-to-day life. Usually what was forgotten can be remembered again by returning to the context where the event began.[14] For example, imagine sitting at your desk and deciding you want to get a drink from the kitchen. Once you get to the kitchen, you completely forget what you wanted there. If you return to your desk, you will most likely remember what you wanted from the kitchen.

There is also evidence to support that our lives and memories may be compartmentalized by our environmental surroundings. Different environments, such as home, the work place, a restaurant or a theater, are associated with different memories and incidentally, different roles.[14] This implies that surroundings cue memories, situations and even personal roles specific to the context a person is in at any given time.

The Outshining Hypothesis

The Outshining Hypothesis is based on the idea that a heavenly body is more difficult to see when it is obscured by a full moon. Similarly, incidental encoding of environmental context-dependent cues can be completely "outshone" when there are better cues available. However, these incidentally encoded environmental cues can be used to prompt memory recall if stronger cues are not present at encoding. A cue may be considered "better" simply because it has been more deeply processed, repeated more often, or has fewer items associated with it.[14] As an example, a study by Steuck and Levy showed that environmental context-dependent memory has a decreased effect in word recall tests if the words are embedded into meaningful text.[14] This is because meaningful texts are stored better in memory and are more deeply processed.

State-dependent learning

State-dependent learning refers to the finding that people recall more information when their physiological state is the same at encoding and retrieval.[15] For example, people that undergo alcohol intoxication while encoding information recall significantly more when they are also intoxicated during retrieval, compared to those whose alcoholic states differ from encoding to retrieval.[16] This state-dependent learning effect has been shown in both human and animal research.[16] ,[17] The state-dependent effect has also been generalized to a variety of drugs, including morphine,[17] cigarettes [18], scopolamine,[15] and nitric oxide [19]


It is important to note, however, that certain drug states impair learning. For example, a study done by Rickles et al. demonstrated that despite the state-dependent effect associated with light marijuana use, people smoking marijuana showed slower learning than people in a placebo group.[20] More precisely, people who consumed marijuana during both the encoding and retrieval phases managed to learn the material in an average of 10 trials, whereas people who were in the placebo condition for both phases learned the same material in only 5.6 trials, on average.

State as a contextual cue

A tentative explanation for state-dependent recall is the use of the physiological state as a contextual cue. [21] Results of converging studies have shown that in tasks where no contextual cue is provided, internal states may serve as contextual cues. Therefore, people who are in a certain drug state at the time of encoding may utilize this state as a cue for retrieval. In contrast, when information is encoded and retrieved in different states, individuals have no cues available to aid them in recalling information, leading to a decline performance. Eich provides further evidence for this theory, demonstrating that the introduction of additional contextual cues abolishes the state-dependent effect.[21] If a cue such as a sound or an image is provided to remind people of what they encoded, they no longer require the state to prompt retrieval. In this instance, participants perform equally, regardless of the states at encoding and retrieval. According to Eich, the complete absence of any other observable reminders is critical for showing state-dependent cueing effects.

Cognitive context-dependent memory

Language of discourse

Cognitive context-dependent memory is a term that describes improved memory recall for information that is both encoded and retrieved in the same cognitive state.[1] The clearest example of a cognitive context-dependent effect has been demonstrated in studies of proficient bilingual speakers, as it has been hypothesized that different languages provide a different cognitive context. It has been shown that both autobiographical and semantic memories could be better recalled when the same language was used for both encoding and retrieval. In particular, Marian and Neisser studied this effect in Russian immigrants to the United States by looking at autobiographical memory. [22] For this study, participants were asked to recall specific autobiographical memories in response to word cues. By varying both the language of the interview (either Russian or English) and the language in which word cues were presented, it was possible to alter which autobiographical memories were recalled. Importantly, interviewing and word-cueing in Russian biased participants towards recalling memories that had occurred in that language.

Matsumoto and Stanley found a similar effect for Japanese-American students. In particular, they demonstrated that cues words written in Japanese were more likely than English cue words to induce memories from participants’ past experiences in Japan.[23] Other studies have suggested similar results for bilinguals in Spanish and English[24], and in Polish and Danish.[25] However, these studies used a different experimental design that does not demonstrate a causal effect. Additionally, Marian and Fausey found an effect of language on recall of semantic information in studies of Spanish-English bilinguals.[26] In particular, they show that accuracy and reaction times are improved for recall of academic information when the language of encoding and retrieval are similar. However, they also suggest that this effect is partially dependent on participants’ language proficiency (i.e. poor English speakers did not show an improvement in scores when English was used for both encoding and retrieval).

"Motivational state"

It has also been suggested that changes in “motivational state” between encoding and retrieval may affect memory recall for events. In a study by Woike et al.[27] participants were asked to read stories of differing motivational contexts and to recall specific information from these stories. The authors found that recall was biased towards stories containing information that matched participants’ own motivational state. Another study by Woike et al. provides a more direct examination of context-dependence by testing the effect of motivational contextual cues on recall of specific word pairs.[28] Specifically, the authors demonstrated that associating word pairs with achievement cues produced a motivational context that increased memory for these word pairs. It should be noted that this study in particular uses neutral motivational cues as a control. These neutral cues did not produce similar improvements in recall for word pairs.

Mood-congruent and Mood-dependent memory

One commonly reported phenomenon is that when individuals are in a "bad mood", they typically recall more bad things having happened to them and evaluate episodes in their lives in a more negative way than usual. It has been suggested that this effect occurs because a person’s mood at any given time has a strong influence on which aspects of their environment seem most salient. This affects what they remember about the past, and what they encode about the present [29]. This particular effect is referred to as mood-congruent and mood-dependent memory.

Mood-congruent memory

Mood-congruent memory has been demonstrated by the finding that emotional material is remembered more reliably in moods that match the emotional content of these memories. [29] For example, when feeling depressed, it is quite typical for an individual to remember more of the negative events in his/her past than of the positive events. Hence, the mood-congruence memory effect refers to better recall for information contained in experiences that match an individual’s current emotional state. This effect has been found to occur for both happy and sad memories. Specifically, happy people will remember more happy than sad information, whereas sad people will better remember sad than happy information. [30] Mood-congruent memory bias has been found for explicit but not implicit memory tasks,[31] which suggests that mood-congruent memory requires an awareness of one's own mood state. [32] There also seems to be a higher occurrence of mood-congruent memory in females, possibly due to a purportedly greater amount of mood awareness. [32] Further evidence for the existence of mood-congruent memory comes from studies demonstrating altered memory recall following experimentally-induced changes in mood using drugs.[33] Additionally, mood-congruent memory bias in explicit memory has been found to be specific to information congruent with negative moods rather than to all negative information. [34] Studies of clinical depression have demonstrated congruent findings. [30]

Mood-dependent memory

Mood dependence is the facilitation of memory when mood at retrieval is matched to mood at encoding. [29] Thus, the likelihood of recalling an event is higher when encoding and recall moods match than when they are mismatched. [35] However, it seems that only authentic moods have the power to produce these mood-dependent effects. [36] It has also been found that events which originate through internal mental operations such as reasoning, imagination and thought are more connected to one's current mood than are those that emanate from external sources—making the former less likely than external events to be recalled after a shift in mood state. [37] Importantly, this role of emotional state in memory recall suggests a potential mechanism for enhancing retrieval of past memories.

Context-dependent forgetting

A large body of research has shown that memory performance is reduced when an individual’s environment differs from encoding to retrieval than if the two environments were the same. This effect is known as context-dependent forgetting. [38] As a result, a number of techniques have been created for the purpose of reducing context-dependent forgetting associated with environmental cues.

Context recall technique

One strategy for overcoming context-dependent forgetting is the context recall technique. This technique involves consciously generating old environmental cues from memory rather than physically reinstating the cued environment. [39] For example, if an individual learned material in a classroom in which the desks were organized in rows, that person could visualize that specific arrangement at a later testing date in a new environment (i.e. with the desks arranged in a circle). In a study conducted by Smith in 1979, participants who used this technique while being tested in a new room were able to recall as many words as participants who were tested in the original learning room [40]. Participants who were tested in a new room that did not use this technique showed typical context-dependent forgetting, recalling only two-thirds of the words recalled by the other groups. [39] Therefore, the effects of context-dependent forgetting can reduced by visualization of the learning environment without full reinstatement.[40] However, this technique is only useful and successful when the learning context is easy to remember. [39]

Multiple learning context technique

The multiple-learning-context-technique is another strategy proposed by Smith to combat context-dependent forgetting. This technique involves presenting subsets of the learning material in multiple contexts rather than presenting them all in the same environment. [39] When given a free recall test in a new room, participants who studied in multiple rooms recalled more words than participants who only studied in one room [39]. Smith suggests that when individuals have additional environmental cues their performance will be sustained because it will be less likely that all of the cues will be forgotten.

Along with the multiple learning context technique, other research has demonstrated that increasing the number of environmental cues will increase an individual's recall performance. [39] The cue-overload theory proposed by Watkins and Watkins in 1975 explains that the effectiveness of an environmental cue will decline when there is an increase in the number of items that it is associated with. [41] Therefore, when given a fixed number of items to recall, performance will increase if the number of cues also increases. [39] This theory focuses on one of the two factors that must be considered when determining the effectiveness of multiple learning environments: the variety of contextual cues. However, research conducted by Jones in 1976 demonstrates that in order for this technique to be useful, the cues must use different senses. [42] For example, there is no recall advantage when only the number of visual cues is increased. On the other hand, there is a recall advantage when different sensory media such as sight, sound, and smell were added together. [43] Hence, this suggests that using multiple sensory media as sources for cues during encoding will provide an advantage in different testing environments where the number of contextual cues has been reduced.

Attention

The second factor to be considered when determining the effectiveness of multiple learning environments is the likelihood that an individual will even use environmental cues when recalling. Instructing subjects to use self-generated cues (i.e. the context recall technique) will increase recall for participants tested in a different environment. However, individuals do not automatically do this when learning occurs in a single location. [39] Therefore, by moving individuals from room to room, they may pay more attention to the environmental cues. Smith claims that both the context recall technique and the multiple learning context technique work similarly, in that both methods force individuals to pay attention to and remember environmental information. [39]

In 2003, Chu et al. demonstrated that conscious effort and attention is important to overcome context-dependent forgetting. Their research has shown that active processing of the context during the encoding phase is an important factor of successful performance. [38] When actively attending to environmental cues with the goal of using a technique such as the context recall technique, stronger associations are created between the material and the environment.[38] However, if an individual does not actively attend to environmental cues during the encoding phase, such cues may not be easily visualized in the recall phase if a new context is present.

Ambient and transferable cues

The word ambient is defined as completely surrounding and encompassing.

Ambient and transferable cues
Music is considered an ambient cue in that it is all encompassing and aids in recall when learning context and recall context are different

Some researchers have suggested that ambient cues, such as odour and sound, aid in recall when the learning context and recall context are different. [43] In addition, these cues are useful in recall because they can also be transferable. For example, if music is played in a room in which material is learned, it is sometimes possible to transfer that musical source to a different room in which material will be tested. This phenomenon, which occurs when a memory or emotion is reactivated by a song that is associated to a specific event, demonstrates the effectiveness of sound (and odour) as useful cues in the absence of the original context.[43] Using transferable cues may be useful for individuals who have difficulty using the context recall technique because they have trouble creating a mental image of the original environment. For example, this technique has been proven useful for patients at home who are trying to reproduce skills that they learned in a hospital environment [43].

Context-dependent extinction

Extinction refers to the loss of performance after a conditioned stimulus is no longer paired with an unconditioned stimulus. It can also refer to the loss of an operant response when it is no longer reinforced. Research done by Bouton (2002) has shown that extinction is not an example of unlearning, but a new type of learning where the performance of the individual is dependent on the context.[44] The renewal effect is seen when a participant is first conditioned in a context (context A) and then shows extinction in another context (B). Returning to context A may renew the conditioned response. This evidence demonstrates that appropriate responses underlying extinction may be linked to contextual information.[44] Hence, if a person is in the context in which he/she initially learned the material, that context is likely to cue this person to act as they were initially conditioned to act. If he/she is in the extinction context, then that context will likely prompt him/her not to respond.

Clinical applications

Extinction is often used in a type of clinical therapy called exposure therapy to treat disorders such as phobias and anxiety and is also used to treat drug dependence. [44] For example, if a person learns to associate snakes with a traumatic event such as being bitten, he or she may develop a phobia. As a treatment, a therapist may choose to expose the person to snakes in the absence of any traumatic event, leading to extinction of maladaptive behaviours related to fear. However, due to the fact that extinction is a context-dependent process, it may lead to relapse once the patient is no longer in the extinction context. [44] In a study by Crombag and Shaham, rats were taught to self-administer a heroin and cocaine mixture followed by twenty days of extinction. Half of the rats experienced extinction in the same context as the original self-administration and the other half in a new context. The rats that underwent extinction in a new context renewed drug self-administration significantly more than the other rats when they were put back in the original context. [45] A similar effect was shown in human exposure therapy for severe fear of spiders. The participants who were treated through extinction and later tested in the same context were significantly less afraid than the participants who were treated and tested in different contexts. This shows the lack of generalizability of one context to another in exposure therapy. [46] Hence, it should be taken into consideration that context-dependence of extinction is critical for successful treatments. In order to acquire stable and effective extinction of phobias, anxiety, or drug-seeking, the context of extinction must be as similar as possible to the day-to-day encounters with emotion-arousing cues that patients may experience.

Tips for studying

student studying
A student is suggested to prepare for an upcoming test by studying in a similar context as he or she is expected to be tested, for example, under silent conditions

According to the literature cited above, information is better recalled when the context matches from encoding to retrieval. Therefore, when a person is studying, he/she should match the studying context as best as possible to the testing context in order to optimize the amount of material that will be recalled. This idea was made apparent in a study done by Grant et al. [47] In this study, participants were asked to study meaningful information under either quiet or noisy conditions. Afterwards, they were asked short-answer and multiple choice questions on the previously learned material, which prompted both recognition and recall. Half of them were tested under silent conditions and the other half under noisy conditions. The participants whose noise-level matched during studying and testing conditions remembered significantly more information than those whose noise-level was mismatched. Grant et al. conclude that students should take into consideration the context of testing, such as the noise level, while studying in order to maximize their performance on both recall and recognition tasks.

Further, in cases where it is not possible to have similar learning and testing contexts, individuals who pay conscious attention to cues in the learning environment may produce better results when recalling this information. By doing so, individuals are better able to create a mental image of the original context when trying to recall information in the new testing context—allowing for improved memory retrieval. [39] Further, several contextual cues should be attended to, using more than one sensory system, in order to maximize the number of cues that can help in remembering information. [39]

References

  1. ^ a b c d e f g Baddeley, A., M. W. Eysenck, and M. C. Anderson. 2009. Memory. Psychology Press, New York, NY, US.
  2. ^ Pessin, J. (1932). The effect of similar and dissimilar conditions upon learning and relearning. J. exp. Psychol. 15, 427-435.
  3. ^ Farnsworth, P.R. (1934). Examinations in familiar and unfamiliar surroundings. J. soc. Psychol. 5, 128-129.
  4. ^ Bilodeau, I. M. & Schlosberg, H. (1951). Similarity in stimulating conditions as a variable in retroactive inhibition. J. exp. Psychol. 41, 119-204.
  5. ^ Strand, B.Z. (1970). Change of context and retroactive inhibition. J. verb. Learn. verb. Behav. 9 202-206.
  6. ^ Jansen, L.C., Harris, K. and Anderson, D. C. (1971). Retention following a change in ambient contextual stimuli for six age groups. Dev. Psychol. 4, 394-399.
  7. ^ a b c d Godden, D, & Baddeley, A. (1975). Context dependent memory in two natural environments. British Journal of Psychology, 66(3), 325-331.
  8. ^ Egstrom, G.G., Weltman, G., Baddeley, A.D., Cuccaro, W.J., and Willis, M.A. (1972). Underwater work performance and work tolerance. Report no. 51, Bio-Technology Laboratory, University of California, Los Angeles.
  9. ^ Smith, S., and E. Vela. 2001. Environmental context-dependent memory: A review and meta-analysis. Psychon. Bull. Rev. (8) 203-220.
  10. ^ Johnson, M.K., Hashtroudi, S., & Lindsay, D.S. (1993). Source Monitoring. Psychological Bulletin, 114 (1), 3-28.
  11. ^ Wagner, A.D., Desmond, J.E., Glover, G.H., Gabrieli, J.D.E. (1998) Prefrontal cortex and recognition memory. Functional-MRI evidence for context-dependent retrieval processes. Brain 121:1985–2002
  12. ^ Kalisch et al. (2006) Context-Dependent Human Extinction Memory Is Mediated by a Ventromedial Prefrontal and Hippocampal Network. The Journal of Neuroscience, 26(37):9503-9511
  13. ^ Wagner, A.D., Desmond, J.E., Glover, G.H., & Gabrieli, J.D.E. (1998) Prefrontal cortex and recognition memory: Functional-MRI evidence for context-dependent retrieval processes. Brain, 121, 1985-2002.
  14. ^ a b c d e f g h i Smith, S.M. (1988) Environmental context-dependent memory. In G. Davies (Ed.), Memory in Context (pp. 13-31). John Wiley & Sons Ltd.
  15. ^ a b Petersen, R.(1979) Scopolamine State-dependent memory processes in man. Psychopharmacology, 64, 309-314. Cite error: The named reference "Pet1" was defined multiple times with different content (see the help page).
  16. ^ a b Goodwin, D., Powell, B., Bremer, D., Hoine, H., & Stern, J. (1969) Alcohol and recall: state-dependent effects in man. Sciences, 163(3873), 1358-1360.
  17. ^ a b Nishimura, M. Shiigi, Y, & Kaneto, H. (1990) State dependent and/or direct retrival by morphine in mice. Psychopharmacology, 100, 27-30. ,
  18. ^ Peters, R., & McGee, R. (1982) Cigarette smoking and state-dependent memory. Psychopharmacology, 76, 232-235.
  19. ^ Mewaldt, S.P., Ghoneim, M.M, Choi, W.W., Kortilla, K., & Peterson, R.C. (1988) Nitrous Oxide and Human State-dependent memory. Pharmacology Biochemistry & Behavior, 30, 83-87.
  20. ^ Rickles, W., Cohen, M.J., Whitaker, C.A., & McIntyre, K.E.(1973) Marijuana induced state-dependent verbal learning
  21. ^ a b Eich, J.M. (1980) The cue-dependent nature of state-dependent retrieval. Memory & Cognition, 157-173.
  22. ^ Marian, V., & Neisser, U. (2000). Language-dependent recall of autobiographical memories. Journal of Experimental Psychology: General, 129(3), 361-368.
  23. ^ Matsumoto, A., & Stanny, C. (2006). Language-dependent access to autobiographical memory in japanese-english bilinguals and US monolinguals. Memory, 14(3), 378-390.
  24. ^ Schrauf, R. W., & Rubin, D. C. (2000). Internal languages of retrieval: The bilingual encoding of memories for the personal past. Memory and Cognition, 28(4), 616– 623.
  25. ^ Larsen, S., Schrauf, R. W., Fromholt, P., & Rubin, D. C. (2002). Inner speech and bilingual autobiographical memory: A Polish-Danish cross-cultural study. Memory, 10(1), 45 – 54.
  26. ^ Marian, V., & Fausey, C. M. (2006). Language-dependent memory in bilingual learning. Applied Cognitive Psychology, 20(8), 1025-1047.
  27. ^ Woike, B. A., Lavezzary, E., & Barsky, J. (2001). The influence of implicit motives on memory processes. Journal of Personality and Social Psychology, 81, 935–945.
  28. ^ Woike, B. A., Bender, M., & Besner, N. (2009). Implicit motivational states influence memory: Evidence for motive by state-dependent learning in personality. Journal of Research in Personality, 43(1), 39-48.
  29. ^ a b c Lewis, P. & Critchley, H. (2003). Mood-dependent memory. Trends in Cognitive Sciences.
  30. ^ a b Mayer, D. McCormick, L. Strong. S. (1995). Mood-Congruent Memory and Natural Mood: New Evidence. Personality and Social Psychology Bulletin, 21(7), 736-746
  31. ^ Watkins, P.C., Vache, K., Vernay, S.P., & Muller, S. (1996). Unconscious mood-congruent memory bias in depression. Journal of Abnormal Psychology, 105, 34-41.
  32. ^ a b Rothkopf, J. & Blaney, P. (1991) Mood congruent memory: The role of affective focus and gender. Cognition & Emotion, 5(1), 53-64.
  33. ^ Klassen, T. Riedel, W.J. Deutz, N.E.P. & Van Praag, H.M (2002). Mood congruent memory bias induced by tryptophan depletion. Psychological Medicine, 32(1),167-172.
  34. ^ Watkins, P.C., Vache, K., Vernay, S.P., & Muller, S. (1996). Unconscious mood-congruent memory bias in depression. Journal of Abnormal Psychology, 105, 34-41.
  35. ^ Eich, E. Macaulay, D. & Ryan, L. (1994) Mood dependent memory for events of the personal past. Journal of Experimental Psychology, 123(2), 201-215.
  36. ^ Eich, E. & Macaulay, D. (2000) Are real moods required to reveal mood-congruent and mood dependent memory? Psychological science, 11(3), 244-248.
  37. ^ Eich, E. and Metcalfe, J. (1989). Mood-dependent memory for internal versus external events. Journal of Experimental Psychology, 15. 3.
  38. ^ a b c Chu, S., Handley, V., & Cooper, S.R. (2003). Eliminating context-dependent forgetting: changing contexts can be as effective as reinstating them. The Psychological Record, 53, 549-559.
  39. ^ a b c d e f g h i j k Smith, S.M. (1984). A Comparison of two techniques for reducing context-dependent forgetting. Memory & Cognition, 12(5), 477-482.
  40. ^ a b Smith, S.M. (1979). Remembering in and out of context. Journal of Experimental Psychology: Human Learning and Memory, 4(5), 460-471.
  41. ^ Watkins, M.J., & Watkins, O.G. (1976). Cue-overload theory and the method of interpolated attributes. Bulletin of the Psychonomic Society, 7(3), 289-291.
  42. ^ Jones, G.V. (1979). Multirate forgetting. Journal of Experimental Psychology: Human Learning and Memory, 5(2), 98-114.
  43. ^ a b c d Parker, A., & Gellatly, A. (1997). Moveable cues: a practical method for reducing context-dependent forgetting. Applied Cognitive Psychology, 11, 163-173.
  44. ^ a b c d Bouton, M.E. (2002) Context, ambiguity, and unlearning: sources of relapse after behavioral extinction. Biol. Psychiatry, 52, 976-986. Cite error: The named reference "Bouton" was defined multiple times with different content (see the help page).
  45. ^ Crombag, H.S., & Shaham, Y. (2002) Renewal of drug seeking by contextual cues after prolonged extinction in rats. Behavioral Neuroscience, 116(1), 169-173.
  46. ^ Mineka, S., Mystkowski, J.L., Hladek, D., & Rodriguez, B.I. (1999) The effects of changing contexts on return of fear following exposure therapy for spider fear. Journal of Consulting and Clinical Psychology, 67(4), 599-604.
  47. ^ Grant, H.M., Bredahl, L.C., Clay, J., Ferrie, J., Groves, J.E., McDorman, T.A., Dark, V.J. (1998) Context-dependent memory for meaningful material: Information for students. Applied Cognitive Psychology, 12, 617-623.
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