The Visual Mandela Effect as Evidence for Shared and Specific False Memories Across People

The Mandela effect is an Internet phenomenon describing shared and consistent false memories for specific icons in popular culture. The visual Mandela effect is a Mandela effect specific to visual icons (e.g., the Monopoly Man is falsely remembered as having a monocle) and has not yet been empirically quantified or tested. In Experiment 1 (N = 100 adults), we demonstrated that certain images from popular iconography elicit consistent, specific false memories. In Experiment 2 (N = 60 adults), using eye-tracking-like methods, we found no attentional or visual differences that drive this phenomenon. There is no clear difference in the natural visual experience of these images (Experiment 3), and these errors also occur spontaneously during recall (Experiment 4; N = 50 adults). These results demonstrate that there are certain images for which people consistently make the same false-memory error, despite the majority of visual experience being the canonical image.

EXPRESS: Where was the Toaster? A systematic investigation of semantic construction in a new virtual episodic memory paradigm

Retrieved memories of past events are often inaccurate. The scenario construction model (SCM) postulates that during encoding, only the gist of an episode is stored in the episodic memory trace and during retrieval, information missing from that trace is constructed from semantic information. The current study aimed to find behavioural evidence for semantic construction in a realistic, yet controlled setting by introducing a new paradigm and adjusted memory tests that measure semantic construction. Using a desktop virtual reality (VR) participants navigated through a flat in which some household objects appeared in unexpected rooms, creating conflicts between the experienced episode and semantic expectations. The manipulation of congruence enabled us to identify influences from semantic information in cases of episodic memory failure. Besides we controlled for objects to be task-relevant or -irrelevant to the sequence of action. In addition to an established old/new recognition task we introduced spatial and temporal recall measures as possible superior memory measures quantifying semantic construction. The recognition task and the spatial recall revealed, that both congruence and task-relevance predicted correct episodic memory retrieval. In cases of episodic memory failure semantic construction was more likely than guessing and occurred more frequently for task-irrelevant objects. In the temporal recall object-pairs belonging to the same semantic room-category were temporally clustered together compared to object-pairs from different semantic categories (at the second retrieval). Taken together, our findings support the predictions of the SCM. The new VR-paradigm, including the new memory measures appears to be a promising tool for investigating semantic construction.

The seven sins of memory: an update

Memory serves critical functions in everyday life, but it is also vulnerable to error and illusion. Two decades ago, I proposed that memory errors could be classified into seven basic categories or "sins": transience, absent-mindedness, blocking, misattribution, suggestibility, bias, and persistence. I argued that each of the seven sins provides important insights concerning the fundamentally constructive nature of human memory, while at the same time reflecting its adaptive features. In this article I briefly summarise some key developments during the past two decades that have increased our understanding of the nature, consequences, and adaptive functions of the memory sins.

Playing "guess who?": when an episodic specificity induction increases trace distinctiveness and reduces memory errors during event reconstruction

The constructive nature of memory implies a possible confusion between details of similar events. Memory interventions should thus target the reduction of memory errors. We postulate that a brief intervention called Episodic Specificity Induction (ESI) facilitates the sensorimotor simulation of event-related details by improving the distinctiveness of the event memory trace. As such, ESI should reduce memory errors only when event memory traces are strongly overlapping based on their sensorimotor features. Participants memorised videos showing characters performing an action on a given object. The characters were either visually very similar to each other or very distinct (low vs. high distinctiveness condition). Next, participants performed either an imagination version of the ESI or a control induction. Finally, a voice announced one of the actions seen and a character was then briefly displayed. The participants had to indicate whether the association was correct. For incorrect associations, in the low distinctiveness condition, false alarms were more likely than in the high distinctiveness condition and were reduced after the ESI. It suggests that facilitating the simulation of specific details through the ESI increased trace distinctiveness and reduced memory errors at the critical time of event reconstruction. Future clinical applications might be possible.

Retrieval-Induced Forgetting in the Feigning Amnesia for a Crime Paradigm

Previous studies demonstrated that, when asked to honestly provide information about a mock crime, former feigners performed worse than those who were requested to confess to this event. Thus, feigning amnesia for a mock crime undermined genuine memory for the same experience. In the present study, we examined whether retrieval-induced forgetting (RIF) underlies this memory-undermining effect. After watching a mock crime, participants had to feign amnesia or confess to having committed that crime. Feigners were given retrieval practice instructions (i.e., retrieval-practice group) or no further instructions (i.e., control group). Immediately and 1 day later, all participants had to genuinely report what they remembered about the crime. Although simulators in the retrieval-practice group recalled the largest amount of information as a positive consequence of retrieval, the ratio for crucial crime-related details was lower than that exhibited by both simulators who were given no instructions and confessors. These findings suggest that RIF might play a role in forgetting critical information in claims of crime-related amnesia. Theoretical and practical implications will be discussed.

Brain Oscillatory Correlates of Visual Short-Term Memory Errors

Brain dynamics of memory formation were explored during encoding and retention intervals of a visual working memory task. EEG data were acquired while subjects were exposed to grayscale images of widely known object categories (e.g., "luggage," "chair," and "car"). Following a short delay, two probes were shown to test memory accuracy. Oscillatory portraits of successful and erroneous memories were contrasted. Where significant differences were identified, oscillatory traits of false memories (i.e., when a novel probe item of the same category is recognized as familiar) were compared with those of successful and erroneous memories. Spectral analysis revealed theta (6-8 Hz) power over occipital channels for encoding of successful and false memories that was smaller when compared to other types of memory errors. The reduced theta power indicates successful encoding and reflects the efficient activation of the underlying neural assemblies. Prominent alpha-beta (10-26 Hz) activity belonging to the right parieto-occipital channels was identified during the retention interval. It was found to be larger for false memories and errors than that of correctly answered trials. High levels of alpha-beta oscillatory activity for errors correspond to poor maintenance leading to inefficient allocation of WM resources. In case of false memories, this would imply necessary cognitive effort to manage the extra semantic and perceptual load induced by the encoded stimuli.

Implicit Memory, Constructive Memory, and Imagining the Future: A Career Perspective

In this article I discuss some of the major questions, findings, and ideas that have driven my research program, which has examined various aspects of human memory using a combination of cognitive, neuropsychological, and neuroimaging approaches. I do so from a career perspective that describes important scientific influences that have shaped my approach to the study of memory and discusses considerations that led to choosing specific research paths. After acknowledging key early influences, I briefly summarize a few of the main takeaways from research on implicit memory during the 1980s and 1990s and then move on to consider more recent ideas and findings concerning constructive memory, future imagining, and mental simulation that have motivated my approach for the past 2 decades. A main unifying theme of this research is that memory can affect psychological functions in ways that go beyond the simple everyday understanding of memory as a means of revisiting past experiences.

Devil in the details? Developmental dyslexia and visual long-term memory for details

Cognitive theories on causes of developmental dyslexia can be divided into language-specific and general accounts. While the former assume that words are special in that associated processing problems are rooted in language-related cognition (e.g., phonology) deficits, the latter propose that dyslexia is rather rooted in a general impairment of cognitive (e.g., visual and/or auditory) processing streams. In the present study, we examined to what extent dyslexia (typically characterized by poor orthographic representations) may be associated with a general deficit in visual long-term memory (LTM) for details. We compared object- and detail-related visual LTM performance (and phonological skills) between dyslexic primary school children and IQ-, age-, and gender-matched controls. The results revealed that while the overall amount of LTM errors was comparable between groups, dyslexic children exhibited a greater portion of detail-related errors. The results suggest that not only phonological, but also general visual resolution deficits in LTM may play an important role in developmental dyslexia.

Stereotype threat can reduce older adults' memory errors

Stereotype threat often incurs the cost of reducing the amount of information that older adults accurately recall. In the current research, we tested whether stereotype threat can also benefit memory. According to the regulatory focus account of stereotype threat, threat induces a prevention focus in which people become concerned with avoiding errors of commission and are sensitive to the presence or absence of losses within their environment. Because of this, we predicted that stereotype threat might reduce older adults' memory errors. Results were consistent with this prediction. Older adults under stereotype threat had lower intrusion rates during free-recall tests (Experiments 1 and 2). They also reduced their false alarms and adopted more conservative response criteria during a recognition test (Experiment 2). Thus, stereotype threat can decrease older adults' false memories, albeit at the cost of fewer veridical memories, as well.

Everyday memory errors in older adults

Despite concern about cognitive decline in old age, few studies document the types and frequency of memory errors older adults make in everyday life. In the present study, 105 healthy older adults completed the Everyday Memory Questionnaire (EMQ; Sunderland, Harris, & Baddeley, 1983 , Journal of Verbal Learning and Verbal Behavior, 22, 341), indicating what memory errors they had experienced in the last 24 hours, the Memory Self-Efficacy Questionnaire (MSEQ; West, Thorn, & Bagwell, 2003 , Psychology and Aging, 18, 111), and other neuropsychological and cognitive tasks. EMQ and MSEQ scores were unrelated and made separate contributions to variance on the Mini Mental State Exam (MMSE; Folstein, Folstein, & McHugh, 1975 , Journal of Psychiatric Research, 12, 189), suggesting separate constructs. Tip-of-the-tongue errors were the most commonly reported, and the EMQ Faces/Places and New Things subscales were most strongly related to MMSE. These findings may help training programs target memory errors commonly experienced by older adults, and suggest which types of memory errors could indicate cognitive declines of clinical concern.