Underestimation of prior remembering and susceptibility to false memories: two sides of the same coin?

In two studies, we explored whether susceptibility to false memories and the underestimation of prior memories (i.e., forgot-it-all-along effect) tap overlapping memory phenomena. Study 1 investigated this issue by administering the Deese/Roediger–McDermott task (DRM) and the forgot-it-all-along (FIA) task to an undergraduate sample (N = 110). It was furthermore explored how performances on these tasks correlate with clinically relevant traits such as fantasy proneness, dissociative experiences, and cognitive efficiency. Results show that FIA and DRM performances are relatively independent from each other, suggesting that these measures empirically apparently refer to separate dimensions. However, they do not seem to define different profiles in terms of dissociation, fantasy proneness, and cognitive efficiency. Study 2 replicated the finding of relative independence between false memory propensity (as measured with the DRM task) and the underestimation of prior memories (as measured with an autobiographical memory dating task) in people with a history of childhood sexual abuse (N = 35).     

Why are there limits on theory of mind use? Evidence from adults' ability to follow instructions from an ignorant speaker

Keysar et al. (Keysar, Barr, Balin, & Brauner, 2000 Keysar, B., Barr, D. J., Balin, J. A. and Brauner, J. S. 2000. Taking perspective in conversation: The role of mutual knowledge in comprehension. Psychological Sciences, 11: 32–38. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Keysar, Lin, & Barr, 2003 Keysar, B., Lin, S. H. and Barr, D. J. 2003. Limits on theory of mind use in adults. Cognition, 89(1): 25–41. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) report that adults frequently failed to use their conceptual competence for theory of mind (ToM) in an online communication game where they needed to take account of a speaker's perspective. The current research reports 3 experiments investigating the cognitive processes contributing to adults' errors. In Experiments 1 and 2 the frequency of adults' failure to use ToM was unaffected by perspective switching. In Experiment 3 adults made more errors when interpreting instructions according to the speaker's perspective than according to an arbitrary rule. We suggest that adults are efficient at switching perspectives, but that actually using what another person knows to interpret what they say is relatively inefficient, giving rise to egocentric errors during communication.     

True and false memory for colour names versus actual colours: Support for the visual distinctiveness heuristic in memory for colour information

In a colour variation of the Deese–Roediger–McDermott (DRM) false memory paradigm, participants studied lists of words critically related to a nonstudied colour name (e.g., “blood, cherry, scarlet, rouge … ”); they later showed false memory for the critical colour name (e.g., “red”). Two additional experiments suggest that participants generate colour imagery in response to such colour-related DRM lists. First, participants claim to experience colour imagery more often following colour-related than standard non-colour-related DRM lists; they also rate their colour imagery as more vivid following colour-related lists. Second, participants exhibit facilitative priming for critical colours in a dot selection task that follows words in the colour-related DRM list, suggesting that colour-related DRM lists prime participants for the actual critical colours themselves. Despite these findings, false memory for critical colour names does not extend to the actual colours themselves (font colours). Rather than leading to source confusion about which colours were self-generated and which were studied, presenting the study lists in varied font colours actually worked to reduce false memory overall. Results are interpreted within the framework of the visual distinctiveness hypothesis.     

Similarity on the rebound: Inhibition of similarity assessment leads to an ironic postsuppressional rebound

A widely held but rarely tested assumption among cognitive scientists is that different cognitive tasks may rely upon a single basic cognitive process. Using an established methodology to examine the suppression and subsequent rebound of mental operations, the present research indicates that suppressing use of similarity in one domain results in the subsequent rebound of similarity assessment in a different domain, suggesting that both domains rely on the same underlying cognitive process. In two studies, we demonstrate that leading people to suppress natural similarity assessment in one task produces increased reliance on similarity in subsequent, different, and apparently unrelated tasks. In Experiment 1, participants led to suppress similarity in a concentration task subsequently made more errors in a false-memory paradigm than did control participants. In Experiment 2, participants suppressing similarity in a categorization task made more false-memory errors and perceived more similarity between word pairs than participants who did not suppress. The findings suggest that the cognitive process of similarity assessment may be a domain-general process, such that it is widespread across a number of different mental tasks.     

False recall in the Deese–Roediger–McDermott paradigm: The roles of gist and associative strength

Theories of false memories, particularly in the Deese–Roediger–McDermott (DRM) paradigm, focus on word association strength and gist. Backward associative strength (BAS) is a strong predictor of false recall in this paradigm. However, other than being defined as a measure of association between studied list words and falsely recalled nonpresented critical words, there is little understanding of this variable. In Experiment 1, we used a knowledge-type taxonomy to classify the semantic relations in DRM stimuli. These knowledge types predicted false-recall probability, as well as BAS itself, with the most important being situation features, synonyms, and taxonomic relations. In three subsequent experiments, we demonstrated that lists composed solely of situation features can elicit a gist and produce false memories, particularly when monitoring processes are made more difficult. Our results identify the semantic factors that underlie BAS and suggest how considering semantic relations leads to a better understanding of gist formation.     

What is “theory of mind”? Concepts,cognitive processes and individual differences

Research on “theory of mind” has traditionally focused on a narrow participant group (preschool children) using a narrow range of experimental tasks (most notably, false-belief tasks). Recent work has greatly expanded the age range of human participants tested to include human infants, older children, and adults, has devised new tasks, and has adopted methods from cognitive psychology and neuroscience. However, theoretical work has not kept pace with these changes, with the result that studies using one kind of method or participant group often inherit assumptions about the nature of theory of mind from other research, with little regard for whether these assumptions are appropriate. I argue that three distinct approaches to thinking about theory of mind are already implicit in research practice, and that future work, whether with infants, children, or adults, will benefit from articulating these approaches more clearly and following their different implications for what theory of mind is and how it should be studied.     

Variation in individuals' semantic networks for common knowledge is associated with false memory

Three experiments assessed the relationships between false memories of words and their degree of connectedness within individual semantic networks. In the first two experiments, participants studied associated word lists (e.g., hot, winter, ice), completed a recognition test that included related nonstudied words (e.g., cold, snow), and then rated the semantic relatedness of all word pairs including studied and nonstudied words. In the third experiment, the task order was reversed; participants completed pairwise ratings and then, two weeks later, completed the false memory task. The relatedness ratings were analysed using the Pathfinder scaling algorithm. In all experiments, items that an individual falsely recognized had higher semantic Pathfinder node densities than those items correctly rejected.     

Differential effects of cue specificity and list length on the prospective and retrospective prospective-memory components

Event-based prospective memory (PM) refers to the ability to remember to perform an intended action at an appropriate moment that is indicated by some cue. It has been shown that increasing the number of PM cues as well as decreasing the cues' specificity can impair PM performance. Although both manipulations result in similar detrimental effects to PM accuracy, they may affect different underlying cognitive processes. To test this hypothesis, we manipulated both the number of cues and cue specificity and found the expected detrimental effects on PM accuracy. Analyses with the multinomial model of PM, which considers false PM responses and accounts for guessing biases, imply that the cue-list-length manipulation affected cue singularisation as well as intention retrieval, whereas cue specificity selectively affected intention retrieval. These results are original evidence that the performance decrements from the two manipulations have different cognitive underpinnings.     

False memories in patients suffering from obstructive sleep apnoea syndrome (OSAS)

We assessed the propensity for false memories among patients with obstructive sleep apnoea syndrome (OSAS). Twenty-one patients with OSAS and 21 controls matched for sex, age and education were recruited. At encoding, an adaptation of the Deese-Roediger-McDermott paradigm was used to induce false memories. At retrieval, participants completed a forced-choice recognition task to distinguish memories based on verbatim traces from those based on gist traces. When the task encouraged retrieval based on either gist or verbatim traces, the groups performed similarly. However, when the task required retrieval based solely on verbatim traces, OSAS patients exhibited poor discrimination and produced more false memories. Our finding that OSAS leads to an increased propensity to produce false memories is discussed within the framework of both fuzzy-trace theory and activation-monitoring theory.     

Infants' understanding of false labeling events: the referential roles of words and the speakers who use them

The four studies reported here examine whether 16-month-old infants' responses to true and false utterances interact with their knowledge of human agents. In Study 1, infants heard repeated instances either of true or false labeling of common objects; labels came from an active human speaker seated next to the infant. In Study 2, infants experienced the same stimuli and procedure; however, we replaced the human speaker of Study 1 with an audio speaker in the same location. In Study 3, labels came from a hidden audio speaker. In Study 4, a human speaker labeled the objects while facing away from them. In Study 1, infants looked significantly longer to the human agent when she falsely labeled than when she truthfully labeled the objects. Infants did not show a similar pattern of attention for the audio speaker of Study 2, the silent human of Study 3 or the facing-backward speaker of Study 4. In fact, infants who experienced truthful labeling looked significantly longer to the facing-backward labeler of Study 4 than to true labelers of the other three contexts. Additionally, infants were more likely to correct false labels when produced by the human labeler of Study 1 than in any of the other contexts. These findings suggest, first, that infants are developing a critical conception of other human speakers as truthful communicators, and second, that infants understand that human speakers may provide uniquely useful information when a word fails to match its referent. These findings are consistent with the view that infants can recognize differences in knowledge and that such differences can be based on differences in the availability of perceptual experience.