False remembering in real life: James Ost's contributions to memory psychology

This special issue honours James Ost's (1973-2019) contributions to our understanding of false and distorted remembering. In our editorial, we introduce some of James' distinctive research themes including the experiences of people who retract "recovered" memories, social (e.g., co-witness and interviewer influence) and personality influences on false remembering, the nature of false remembering itself (e.g., different types of false memories; false memories vs. false beliefs), public understanding of (false) memory, and a historical link to the work of Frederic Bartlett. We illustrate these themes through a number of key publications. The unifying thread behind James' work is his core interest in false/distorted remembering in real-life (typically high-stake) situations, in line with his engagement with the British False Memory Society and his role as an expert witness in court trials. The articles included in this special issue elaborate on the research themes to which James devoted his career and his curiosity.

Remembering Molly: Immediate and delayed false memory formation after acute MDMA exposure

The entactogen 3,4-Methylenedioxymethamphetamine (MDMA) is increasingly being recognized for its therapeutic potential but is also widespread in nightlife settings where it may co-occur with crime. Since previous research detected impaired verbal memory during acute MDMA intoxication, understanding the drug's ramifications in an applied legal context becomes crucial. We conducted a double-blind, placebo-controlled trial to examine acute and delayed effects of MDMA (75 mg) on false memory in 60 healthy volunteers with a history of MDMA use, using three well-established false memory methods: a basic, associative word list (Deese/Roediger-McDermott (DRM)) paradigm and two applied misinformation tasks using a virtual reality crime. Memory was tested immediately (encoding and retrieval under drug influence) and 1 week later (retrieval when sober). Small MDMA-induced impairments of true memory in the word list task were detected at both time points. MDMA increased false memory for related but non-critical lures during the immediate test, and decreased false memory for critical lures after a delay. Episodic memory assessed in the misinformation tasks was not consistently affected. Findings indicate a complex memory profile but no heightened vulnerability to external suggestion in response to MDMA intoxication. Recommendations for future applied legal psychological research include adding measures of recall on top of recognition, using study designs that separate the different memory phases, and potentially testing higher doses. Further research on false memories and suggestibility using imagination procedures can also be relevant for the clinical context.

Does Test Type Influence False Recognition in the DRM Paradigm? Comparison of the Yes/No Recognition Test and Two-Alternative Forced-Choice Test

Studies attempting to identify the mechanisms that are responsible for the level of false recognition in the DRM paradigm usually apply a manipulation during encoding. The main aim of the studies reported here was to investigate the within- and between-participant effects of a testing method on memory performance using a standard yes/no recognition test and a 2-alternative forced-choice recognition test (2FC). To allow a direct comparison of the 2 testing methods, a 2FC test containing similar items as a typical yes/no test in the DRM paradigm was elaborated on in the pilot study. Moreover, 2 methods of data calculation were used: comparing rates of hit and false alarms with critical lures and with unstudied and unrelated items between the 2 tests and comparing measures of sensitivity (d’) derived from signal detection theory. Both experiments showed a lower false alarm rate to critical lures and higher hit rate in a 2FC test as compared with a yes/no test, depicting a typical mirror effect. A within-participant design (Experiment 1) also showed that this increased accuracy of a 2FC test diminished when memory performance was expressed in terms of a sensitivity measure, which may suggest that similar processes are used during these 2 retrieval methods. A similar analysis performed for a between-participants design (Experiment 2) revealed that a 2FC test was less susceptible to associative memory distortions, but the quality of memory (“remember/know” judgments) remained similar for both tests.

Cannabis increases susceptibility to false memory

With the growing global acceptance of cannabis and its widespread use by eyewitnesses and suspects in legal cases, understanding the popular drug's ramifications for memory is a pressing need. In a double-blind, randomized, placebo-controlled trial, we examined the acute and delayed effects of Δ9-tetrahydrocannabinol (THC) intoxication on susceptibility to false memory in 64 healthy volunteers. Memory was tested immediately (encoding and retrieval under drug influence) and 1 wk later (retrieval sober). We used three different methods (associative word lists and two misinformation tasks using virtual reality). Across all methods, we found evidence for enhanced false-memory effects in intoxicated participants. Specifically, intoxicated participants showed higher false recognition in the associative word-list task both at immediate and delayed test than controls. This yes bias became increasingly strong with decreasing levels of association between studied and test items. In a misinformation task, intoxicated participants were more susceptible to false-memory creation using a virtual-reality eyewitness scenario and virtual-reality perpetrator scenario. False-memory effects were mostly restricted to the acute-intoxication phase. Cannabis seems to increase false-memory proneness, with decreasing strength of association between an event and a test item, as assessed by different false-memory paradigms. Our findings have implications for how and when the police should interview suspects and eyewitnesses.

Sleep does not cause false memories on a story-based test of suggestibility

Sleep contributes to the consolidation of memories. This process may involve extracting the gist of learned material at the expense of details. It has thus been proposed that sleep might lead to false memory formation. Previous research examined the effect of sleep on false memory using the Deese-Roediger-McDermott (DRM) paradigm. Mixed results were found, including increases and decreases in false memory after sleep relative to wake. It has been questioned whether DRM false memories occur by the same processes as real-world false memories. Here, the effect of sleep on false memory was investigated using the Gudjonsson Suggestibility Scale. Veridical memory deteriorated after a 12-h period of wake, but not after a 12-h period including a night's sleep. No difference in false memory was found between conditions. Although the literature supports sleep-dependent memory consolidation, the results here call into question extending this to a gist-based false memory effect.

Do emotional stimuli enhance or impede recall relative to neutral stimuli? An investigation of two "false memory" tasks

Many eyewitness memory situations involve negative and distressing events; however, many studies investigating "false memory" phenomena use neutral stimuli only. The aim of the present study was to determine how both the Deese-Roediger-McDermott (DRM) procedure and the Misinformation Effect Paradigm tasks were related to each other using distressing and neutral stimuli. Participants completed the DRM (with negative and neutral word lists) and viewed a distressing or neutral film. Misinformation for the film was introduced and memory was assessed. Film accuracy and misinformation susceptibility were found to be greater for those who viewed the distressing film relative to the neutral film. Accuracy responses on both tasks were related, however, susceptibility to the DRM illusion and Misinformation Effect were not. The misinformation findings support the Paradoxical Negative Emotion (PNE) hypothesis that negative stimuli will lead to remembering more accurate details but also greater likelihood of memory distortion. However, the PNE hypothesis was not supported for the DRM results. The findings also suggest that the DRM and Misinformation tasks are not equivalent and may have differences in underlying mechanisms. Future research should focus on more ecologically valid methods of assessing false memory.

Interactions between spontaneous instantiations to the basic level and post-event suggestions

Extensive research shows that post-event suggestions can distort the memory for a target event. In this study we examined the effect of such suggestions as they interact with the products of a spontaneous memory process: instantiation of abstract information to an intermediate level of abstractness, the basic level (Pansky & Koriat, 2004 ). Participants read a narrative containing items presented at the superordinate level (e.g., FRUIT), were exposed to suggestions that referred to these items at the basic level (e.g., APPLE), and were finally asked to recall the original items. We found that the tendency to instantiate spontaneously in the control (non-misleading) condition, particularly over time, increased following exposure to suggestions that were likely to coincide with those instantiations. Exposure to such suggestions, either immediately or following a 24-hour delay, reduced subsequent correct recall of the original items only if the suggested information coincided with the information one tends to instantiate spontaneously in a given context. Suggestibility, in this case, was particularly pronounced and phenomenologically compelling in terms of remember/know judgements. The findings are taken to imply that effects of post-event suggestions can be understood in terms of the constructive processes that set the stage for their occurrence.

The extended mind and borderline personality disorder

OBJECTIVES

Extended mind theory, a recent development in the field of cognitive philosophy, suggests that the information and processes contained in external objects such as notebooks and computers can be considered as much a part of a person's mind as the processes contained within the brain itself. This paper aims to outline extended mind theory, and to explore how it might be applied to an understanding of psychiatric conditions such as borderline personality disorder (BPD).

CONCLUSION

Those with BPD have a deficit in their ability to perform certain high-level cognitive tasks, such as regulation of affect and impulse control. They incorporate the brains of people close to them, to supplement their own brains when performing these tasks. Using an external object or person as part of one's own cognitive apparatus demands nearly constant proximity and an exceptionally intimate informational bond. This would account for the BPD sufferer's panic and despair in the face of abandonment--when abandonment means literally losing one's mind, it could seem worth any effort or risk to avoid such a loss. Further application of extended mind theory to other psychiatric phenomena is also considered.