Context-Dependent Memory

Context-Dependent Memory

When we learn and memorize new information, our brain also stores associated information from the surrounding area. Contextual cues such as the spatial layout of a room or even its smell are gathered and integrated alongside the new material being learned. Then, during retrieval, if the environment is the same, the stored contextual information activates automatically, providing a deeper interconnected neural network of associated information, improving recall performance. This idea, that recall memory performance is better when tested in the same environment as the initial learning, is best described as context-dependent memory (Anderson, 2010, p. 196).

The following three studies most dramatically showcase the context-dependent memory phenomenon. First tested by Godden & Baddeley (1975), then replicated and enhanced by Finn et al. (2010), then further tested and disrupted by Schwabe et al. (2009). Together, these experiments help further our understanding of learning environments that enhance recall and retrieval performance. 

Godden & Baddeley (1975) were one of the first to show conclusive evidence of context-dependent memory. Hypotheses and theories about context-dependent memory previously were either inconclusive, speculative or the effects were generalized only to a laboratory setting. In their free recall experiment “Context-Dependent Memory in Two Natural Environments: On Land and Underwater,” Godden and Baddeley proved their hypothesis that when “performance learning and recall took place in the same environment [it was] significantly better than when recall took place in a different environment to that of learning” (p. 326).  This hypothesis was based on the belief that what is learned in a given environment is best recalled in that same environment.

Eighteen subjects were tested. 13 male and 5 females divers were split into four groups of four (2 subjects were tested later due to technical difficulties) and tested on their ability to recall a random list of words in two different scenarios. In the first scenario, the subjects used the same environment to learn and then recall the words, either both underwater in full scuba gear or both on dry land with normal attire. In the second condition, the environment to learn and then recall were different. The subjects either learned underwater then tested on dry land, or learned on dry land and then tested underwater. Each word list contained 36 unrelated words which were presented to the subjects on recorded tape in blocks of three words. Each list was presented twice with a 10 second interval between presentations. After the second presentation a quick writing task was performed to eliminate any possibly primary memory effects. Then they were asked to recall as many words as possible.

In the condition where learning and recall environments were the same, the subjects scored significantly higher than when the environments were different. There was no significant difference between scores in the same environment, suggesting that both environments were equally advantageous.  Since there was some delay switching between the different environments, a second experiment was run to test if any advantage was given to the extra study time. In this test, 16 subjects were required to dive into the water during the 4 minute delay between presentation and the subsequent dry test. The extra time showed no significant advantage. The results of this study were one of the first times strong experimental evidence of contextual memory was seen. But considering the participants only studied seemingly arbitrary word lists, it was hard to see the practical use contextual-memory had.

In a more recent study, Finn et al. (2010) suggested that the original Godden & Baddeley (1975) experiment, though powerful, failed to test subjects in a real-world setting. The goal of “The Impact of Wearing Scrubs on Contextual Learning” (2010) was to see if “seemingly trivial contexts, such as clothing” had an impact on learning and recall (p. 381). Furthermore, since the vast majority of medical education takes place in a classroom or laboratory, where medical students are faced with real-world situations, they are expected to recall information in an environment that is vastly different from where they learned it. This could lead to poorer performance for medical students in their first real-world clinical settings.

82 medical students completed all aspects of the experiment. They first were required to take a pre-test to establish a baseline of their existing knowledge on anatomy. The pre-test consisted of 12 multiple-choices questions. All students were then divided into eight randomly assigned groups and issued ceil-colored scrubs. Depending on the group allocation, students either wore scrubs or their own clothes during the first anatomy teaching session. Each group was tested immediately after the teaching session. This test was in the same format as the pre-test, 12 multiple choice questions. Students then changed into the opposite clothing and attended a different anatomy teaching session. They were then subsequently tested using the same format as before. Finally, after five weeks, students completed two post-tests, one for each session, in their own clothes, online.

In the condition where the contexts were the same (either wearing their own clothes for both tests or scrubs for both tests), scores were significantly higher than when the contexts were different (p. 382). Students recalled significantly more information when examined in the same context they were taught. This essentially replicated the results of the Godden & Baddeley (1975) study, however, it was a significant result in its own right given the seemingly trivial context of clothing. These results imply that medical education should move towards simulated contexts during lecturing to improve recall during real-world clinical environments. Since scrubs are commonplace in clinical practice, this study suggests that scrubs should also be worn during training and learning as well.

But what if the benefits of contextual-memory could be disrupted? In “Stress Disrupts Context-Dependent Memory,” Schwabe et al. (2009) suggested that since the brain structures for contextual memory, the hippocampus and prefrontal cortex, also have high density of cortisol receptors (stress receptors), context-dependent memory could be disrupted (p. 110). Since stress suppresses memory-related processes such as spatial or working memory, Schwabe et. al. suggested that contextual learning could also be similarly impacted by stress, essentially reducing or completely removing the beneficial effects.

72 young adults split up into four groups of 9 women and 9 men participated in the study. Participants were screened for any pre-existing health issues that could affect the stress results. Before the experiment they were asked to refrain from doing anything that could affect their stress levels, such as consuming caffeine or participating in severe physical exercise. The test was a computer version of the card game “memory” where 15 card pairs were laid face down and participants then choose two cards to turn face up to see if they were the same or not. If not, the second card was turned face down and they continued to search the other cards until they found a match. This was repeated until all card pairs were found. Participants were given four trials to memorize the spatial arrangement of the randomized card pairs. During this learning phase, the room was filled with a vanilla odor as earlier studies have shown odors can facilitate memory (p. 110).

Before the memory card learning phase, however, participants were either subjected to a stress condition or no stress in the control condition. In the stress condition, participants immersed their hands in ice water for up to 3 minutes as described by the “socially evaluated cold pressor test” or SECPT as a legitimate, ethical way to produce stress in participants of study (p. 110). In the control condition, participants placed their hands into warm water. Saliva samples were taking before, during and after the stress test to measure cortisol concentrations. Blood pressure and each subject’s verbal ratings of stress were also calculated.  Because cortisol levels reach peak levels after 20 minutes, twenty-five minutes elapsed before the memory test began.  To control for the diurnal rhythm of stress, testing took place between 1:00 p.m. and 5:30 p.m.

The following 24-hour period, retention performance was tested either in the same, congruent context (same room and same scent) or in a different, incongruent context (new room without the scent). The measure of performance was the number of correct pair locations without error and the time needed to complete the memory game as compared to the last trial 24 hours before. Participants in the control group showed significantly better memory performance if the recall and learning environment were the same (p. 111), about 30% better than the stress group. When subjects were stressed before learning, these enhancements essentially disappeared. Stress, therefore, impaired and interfered with the participant’s ability to integrate contextual cues into memory, a phenomenon commonly seen in post-traumatic stress disorder patients.

With reasonable confidence, these studies suggest that a context-dependent phenomenon does exist and that recall performance depends upon the environment of learning. Context-dependent memory helps to give a deeper understanding and also improves long-term knowledge decay. The scrubs study enhanced and replicated the original findings of Godden & Baddely (1975) by using seemingly trivial items such as clothing, and it also showed that simulation, especially of real-world environments, is part of contextual memory as well.

In order for learners to become better members of the community, they must also learn to function as part of the culture and content of the community. Learning from experience using contextual memory, rather than from abstractions in textbooks seems to contribute to this “situated learning” experience and improve community and real-world assimilation. Authentic aspects of simulation may then provide a way to bridge the gap between classroom learning and legitimate contexual participation. The high level of authenticity in these simulations have a significant, safe and supportive impact on learning.

However, to be beneficial, great care must be taken to ensure learning environments not only mimic real-world situations but are relaxed and relatively stress free. When stressed, we tend to discount contextual cues and simply focus on information related to the primary task. Associated cues are not integrated into our memories and the information learned sits relatively “alone” in our brain. Retrieval and recall suffer, leading to poor performance in experimental and real-world scenarios. Successful learning and recall, therefore, depend heavily on stress-free, authentic or congruent environments.

Anderson, John. (2009). Cognitive Psychology and its Implications, 7^th Ed. New York: Worth Publishers. Print.

Finn, Gabrielle, Debra Patten and John McLachlan. (2010). “The Impact of Wearing Scrubs on Contextual Learning.” Medical Teacher. 32(5), 381-384 doi: 10.3109/01421590903437196

Godden, D.R and A.D. Baddeley. (1975). “Context-Dependent Memory in Two Natural Environments: On Land and Underwater.” British Journal of Pscyhology 66(3), 325-31. Retrived from http://www.niu.edu/user/tj0dgw1/classes/411/GoddenBaddeley1975.pdf

Schwabe, Lars, Andreas Bohringer, and Oliver Worlf. (2009). “Stress Disrupts Context-Dependent Memory.” Learning & Memory, 16, 110-113. doi:10.1101/lm.1257509