False memories: How emotional distracters affect recall and recognition

False memories: How emotional distracters affect recall and recognition

False memory encompasses human recollections that are distorted from the event that actually took place, or fabricated entirely. These errors in memory can be thought of in two distinct categories: ‘commission’ and ‘omission’. Commission memory error refers to the creation, or ‘commission’, of a memory that did not actually occur, as opposed to ‘omission’ where a true memory is forgotten. The pioneering research of Bartlett (1932) suggested that an individual’s recollection of the past is  of past events is shaped by their own schemas and understandings of the present. This foundational hypothesis guided subsequent investigations in false memory  Understanding of false memories has practical applications in many sectors of society, as it has been in analysing false recollections of abuse that patients have formed in therapy (Roediger & McDermott, 1995). The foundation of empirical research into this phenomenon is often cited back to Bartlett (1932), whereby the recall of elements of a popular Indian folktale was warped with the cultural expectations of the British participants. Bartlett’s pioneering research suggests that an individual’s reconstruction of past events is shaped by their own schemas and understandings of the present, but offers little scientific explanation of this. Another noteworthy contribution of his research was the distinction made between reproductive memory, which was evidenced in his British subjects reproducing a story they had been told, and reconstructive memory, whereby individuals are asked to ‘fill in’ the gaps of a memory (Bartlett, 1932). It is both of these two types of memory – recall and recognition respectively – with which our present study is concerned.

The research of Deese (1959) was important in the detection of ‘extralist intrusions’ in free recall, but it was largely unexplored until later developed by Roediger and McDermott (1995). The two separate studies in conjunction offer a more precise understanding of false recall as a by-product of activating semantic, cognitive networks in the brain. Deese, Roediger and McDermott’s combined research formed the basis of the Deese-Roediger-McDermott (DRM) paradigm, which has been replicated in subsequent experiments pertaining to false memory. A DRM test typically involves presenting participants with lists of words, typically 12 words, which are all semantically related to a critical non-presented, or ‘lure’, word. When asked to recall the words after each list is presented, a significant number of participants confidently recall seeing the word to which all of the shown words are related, even though this word was never shown itself. A popular example of this test would be the words ‘snooze’, ‘tired’, ‘bed’, etc being presented and forming a false memory of seeing the lure word ‘sleep’ (Roediger & McDermott, 1995). The rationalization for this false memory is, according to Spreading Activation Theory, that the presentation of each word activates a semantic network in the brain that includes the lure word (Gallo, Roberts & Seamon, 1997). As the same semantic network is continuously engaged, the lure word is eventually encoded as a false memory. The physiological explanation as to how the memory is created is not explored in either Deese or Roediger and McDermott’s research, but other studies have hypothesized it as an error in the encoding or retrieval process (McDermott & Watson, 2001), or a criterion shift adopted during retrieval (Miller & Wolford, 1999 as cited in McDermott & Watson, 2001). Irrespective, the DRM paradigm forms the foundation for a large amount of empirical research on false memory, and is central to our experimentation.

From the foundational question of whether or not false memories can be created, experimenters have become interested in what factors could influence the strength or potency of a false memory. Backwards Associative Strength (AS) refers to the probability that a listed word semantically activates the lure word (Browning, 2009). As an example, the probability of the list word ‘bed’ activating the lure word ‘sleep’ is .638 (Nelson, McEvoy, & Schreiber, 1998 as cited in Browning, 2009). The higher the BAS, the more likely a false memory will be encoded. Other factors that have been shown to influence the strength of a false memory are the length of the lure word and the number of times the lure word appears in print, known as its ‘raw frequency’ (Roediger et al., 2001 as cited in Browning, 2009). McDermott and Watson’s 2001 study showed that longer presentation duration of list words weakens the false memory of a lure word, whilst Gallo, Roberts and Seamon’s 1997 research found that a forewarning about false memories did serve to minimise false recall, but not false recognition, of lure words.

A particular factor with which the second part of our study is concerned is the effect of emotional connotation in the list and lure words. Choi, Kensinger and Rajaram (2013) contend that the distinctive nature and ‘conceptual relatedness’ of emotional words mean that they have a distractive effect over other words. Emotionally distracting words, both in the list and lure words in a DRM task, can disrupt the encoding process of a memory.

The aims of the present study are twofold. The experiment aimed to ascertain whether or not DRM lists will produce a false memory effect. That is, it intended to find out to what extent participants will falsely state having seen the lure word, at both the stages of recall and recognition. The other aim of the experiment was to measure the effect of inserting an emotionally distracting word in the DRM list on the actual given words, and the lure words, at the stages of recall and recognition.

It was hypothesised that a false memory effect would indeed be induced by the DRM lists, and would be recorded during testing of both recall and recognition. Also, it was predicted that the emotionally distracting word would improve the recall and recognition of the actual given words, but will reduce both the recall and recognition of the lure words.

References

Bartlett, F. C. (1932). Remembering: A study in experimental and social psychology. Cambridge, UK: Cambridge University Press.

Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58(1), 17-22.

Roediger, H. L., & McDermott, K. B. (1995). Creating false memories: remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory and Cognition, 21(4), 803-814. doi: 10.1037/0278-7393.21.4.803

McDermott, K. B., & Watson, J. M. (2001). The rise and fall of false recall: The impact of presentation duration. Journal of Memory and Language, 45(1), 160-176. doi: 10.1006/jmla.2000.2771

Browning, E. S. (2009). Backward associative strength and illusory recollection: Extension of the source-strength effect to item location (Unpublished master’s thesis). The University of New Mexico, Albuquerque, New Mexico.

Gallo, D. G., Roberts, M. J., & Seamon, J. G. (1997). Remembering words not presented in lists: Can we avoid creating false memories?. Psychonomic Bulletin & Review, 4(2), 271-276. doi: 10.3758/BF03209405

Choi, H-Y., Kensinger, E. A., & Rajaram, S. (2013). Emotional content enhances true but not false memory for categorized stimuli. Memory & Cognition, 41(3), 403-15. doi: 10.3758/s13421-012-0269-2