State-dependent retrieval describes the experimental finding that subjects who learn something in one state (e.g., a drug, nondrug, or mood state) remember more if they recall in the same state, rather than in a changed state. Context-dependent retrieval describes the same phenomenon. Numerous states or contexts can act as retrieval cues to facilitate remembering if reinstated at recall. Graham Davies and Donald Thomson (1988) provide an excellent reference source describing the different contexts found to influence memory. These include external states, where the learning environment is reinstated (e.g., the room, or a crime scene), and internal states, where the inner experiential state is reinstated (e.g., with alcohol, drugs, or mood states). In one experiment with subaqua divers, the divers who learned and recalled word lists in the same context (on land or under water) remembered 50 percent more words. In another experiment, subjects performed memory tasks while sober or under the influence of alcohol. Twenty-four hours later they were tested under the same or different conditions; those who learned and recalled in the same state remembered more than those who changed states. Endel Tulving and Donald Thomson proposed that specific retrieval cues facilitate recall if the information about them is encoded and stored at the same time as the material to be remembered (Tulving and Thomson 1973). Their “Encoding Specificity” principle states that a cue must reinstate information present in the original memory trace to be effective at retrieval.
State-dependent retrieval has been studied extensively in animals using drugs to induce state changes. Donald Overton (1974) commented that many experiments using pharmacologically induced states suffer from methodological problems. Eric Eich (1980) reviewed fifty-seven experiments of human drug state-dependent retrieval and noted that the phenomenon is not always reproducible; it is also unclear whether drugs exert an influence directly on memory or indirectly through changes in mood.
Researchers became interested in the effects of mood on memory, particularly the perpetuation of depressive mood states. Mood was thought to have a state-dependent effect on memory. This suggestion arose from the findings of studies in the 1980s by John Teasdale (1983) and others that happy past memories were significantly more likely to be retrieved in happy moods and sad memories more often in depressed moods. These mood congruity effects were thought to result from mood state acting as a context; support for the mood-state-dependent retrieval explanation came from experiments demonstrating that similarity of mood state at time of encoding and retrieval produced less forgetting of emotionally neutral material than changed mood states. Gordon Bower (1981) advanced his “Associative Network Theory of Memory and Emotion” to explain these findings, but controversy surrounded mood-state-dependent retrieval; the effect was elusive and unpredictable (Blaney 1986; Kuiken 1991). Analysis of experiments investigating mood-state-dependent retrieval identified methodological problems that contributed to the controversy surrounding the reliability of the effect (Kenealy 1997). In particular, designs confounded encoding and retrieval by not measuring (or reporting) initial learning scores; some lacked objective measures of mood manipulation; and others used the same method of mood induction at encoding and retrieval, confounding the effects of mood and induction procedure. The phenomenon is intriguing, but the evidence does not allow definitive statements to be made concerning the generality and reliability of state-dependent retrieval.
Blaney, Paul H. 1986. Affect and Memory: A Review. Psychological Bulletin 99: 229–246.
Bower, Gordon H. 1981. Mood and Memory. American Psychologist 36: 129–148.
Davies, Graham M., and Donald M. Thomson, eds. 1988. Memory in Context: Context in Memory. Chichester, U.K.: John Wiley and Sons.
Eich, Eric. 1980. The Cue-Dependent Nature of State-Dependent Retrieval. Memory amd Cognition 8: 157–173.
Gerrards-Hesse, Astrid, Kordelia Spies, and Friedrich W. Hesse. 1994. Experimental Inductions of Emotional States and Their Effectiveness: A Review. British Journal of Psychology 85: 55–78.
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Kenealy, Pamela M. 1997. Mood-State-Dependent Retrieval: The Effects of Induced Mood on Memory Reconsidered. Quarterly Journal of Experimental Psychology 50A: 290–317.
Kuiken, Don, ed. 1991. Mood and Memory: Theory, Research, and Applications. Newbury Park, CA: Sage.
Peeters, Rudi, and Géry d’Ydewalle. 1987. Influences of Emotional States Upon Memory: The State of the Art. Communication & Cognition 20: 171–190.
Teasdale, John D. 1983. Negative Thinking in Depression: Cause, Effect or Reciprocal Relationship? Advances in Behavious Research & Therapy 5: 3–25.
Tulving, Endel, and Donald M. Thomson. 1973. Encoding Specificity and Retrieval Processes in Episodic Memory. Psychological Review 80: 353–373.
Pamela M. Kenealy