Memory Illusions Research Articles

Pupil response patterns distinguish true from false memories

Memory is reconstructive and error-prone, which make memory illusions very common in everyday life. However, studying memory illusions can provide valuable insights into how memory works. Pupil response has emerged, in recent years, as an indicator of memory encoding and retrieval, however its validity as a measure of memory success is debated. In this study, we explored whether pupil response patterns can differentiate true from false memories and whether variations in the temporal dynamics of pupil response can elucidate the mechanisms underlying false memory creation. The Deese-Roediger-McDermott (DRM) paradigm was employed to generate false memories in two separate experiments involving visual and auditory stimuli. Pupil responses effectively differentiated true from false memories based on variations in pupil amplitude at different temporal components. This discrimination remained consistent across both experiments, with slightly stronger effects in the auditory condition, aligning with the more pronounced false memory effects in this condition. Notably, differential pupil responses between true and false memories varied based on the type of memory involved at recognition. These findings provide valuable insights into the cognitive processes underlying memory distortions, with implications for theoretical frameworks and real-world contexts.

Theoretical explanations of developmental reversals in memory and reasoning

Developmental reversals are puzzling situations in which cognitive development seems to be devolving rather than evolving because reasoning and memory become more illogical and biased with age. The theoretical conundrum is to explain how underlying processes that mature in the normal way could nevertheless cause specific forms of reasoning and memory to seem to devolve. Currently, there are several competing explanations, which can be divided into two broad categories: (a) an explanation that actually predicted several developmental reversals before they were identified empirically and (b) several other explanations that attempt to account for reversals after the fact. Concerning a, fuzzy-trace theory predicted developmental reversals for certain reasoning illusions (e.g., decision framing, conjunction fallacies) and memory illusions (e.g., false memory paradigms) that had been extensively studied in adults. The key idea was that illusions in both domains derive from an ability that develops slowly, the tendency to rely on semantic gist. This explanation has stimulated a substantial research literature, which includes critical tests of its predictions. Concerning b, the alternative explanations can be grouped into major accounts and minor accounts. The major alternatives (the developmental deficit and associative network hypotheses) have generated substantial research, but neither explains the full range of developmental reversals. The minor alternatives (the working-memory capacity, item and relational encoding, recollection and familiarity, and perceptual and conceptual style hypotheses) have generated only limited research, and they also do not explain the full range of developmental reversals.

Seeing Ɔ, remembering C: Illusions in short-term memory.

Perception can be shaped by our expectations, which can lead to perceptual illusions. Similarly, long-term memories can be shaped to fit our expectations, which can generate false memories. However, it is generally assumed that short-term memory for percepts formed just 1 or 2 seconds ago accurately represents the percepts as they were at the time of perception. Here 4 experiments consistently show that within this timeframe, participants go from reliably reporting what was there (perceptual inference accurately reflecting the bottom-up input), to erroneously but with high confidence reporting what they expected to be there (memory report strongly influenced by top-down expectations). Together, these experiments show that expectations can reshape perceptual representations over short time scales, leading to what we refer to as short-term memory (STM) illusions. These illusions appeared when participants saw a memory display which contained real and pseudo-letters (i.e. mirrored letters). Within seconds after the memory display disappeared, high confidence memory errors increased substantially. This increase in errors over time indicates that the high confidence errors do not (purely) result from incorrect perceptual encoding of the memory display. Moreover, high confidence errors occurred mainly for pseudo-to-real letter memories, and much less often for real-to-pseudo-letter memories, indicating that visual similarity is not the primary cause of this memory-bias. Instead 'world knowledge' (e.g., which orientation letters usually have) appear to drive these STM illusions. Our findings support a predictive processing view of the formation and maintenance of memory in which all memory stages, including STM, involve integration of bottom-up memory input with top-down predictions, such that prior expectations can shape memory traces.

Filling global gaps in monitoring data with local knowledge

Filling global gaps in monitoring data with local knowledge

Predictive Processing of Scene Layout Depends on Naturalistic Depth of Field

Boundary extension is a classic memory illusion in which observers remember more of a scene than was presented. According to predictive-processing accounts, boundary extension reflects the integration of visual input and expectations of what is beyond a scene’s boundaries. According to normalization accounts, boundary extension rather reflects one end of a normalization process toward a scene’s typically experienced viewing distance, such that close-up views give boundary extension but distant views give boundary contraction. Here, across four experiments (N = 125 adults), we found that boundary extension strongly depends on depth of field, as determined by the aperture settings on a camera. Photographs with naturalistic depth of field led to larger boundary extension than photographs with unnaturalistic depth of field, even when distant views were shown. We propose that boundary extension reflects a predictive mechanism with adaptive value that is strongest for naturalistic views of scenes. The current findings indicate that depth of field is an important variable to consider in the study of scene perception and memory.

The phenomenon of false memory in minors in the practice of a clinical psychologist and investigator

The article examines the phenomena of false memory, motives of destructive behavior, lying as a sociocultural phenomenon, draws attention to the psychopathological form of lies. Two clinical cases are described using a questionnaire interview in the practice of a clinical psychologist and an investigator. Appealing to scientific views and law enforcement practice, the authors draw their own conclusions about the possibility and importance of correcting true memories from false ones, since any person has the ability to form detailed false memories. False memories are simply illusions of memory caused by normal processes for it.

Self-referential processing in false recognition and source monitoring: Self-other differences

ABSTRACT The present experiment examined the effect of self, close other, and unknown other-references on false recognition and source monitoring in the Deese-Roediger-McDermott (DRM) paradigm. In the present study, participants were shown items with their own name, the name of a closely known other, an unknown other, or alone. Then, they were asked to recognise the items and the reference conditions. The results showed that the items paired with oneself and a closely known other lead to higher true recognition scores compared to other two conditions. Moreover, the source of the items in the self and the close other-reference conditions were more likely to be attributed to the correct sources than the latter two. However, the self and the close other-referenced items increased false recognition and source misattribution scores. The findings indicate that referencing the self and close others may lead to memory illusions via distorting source monitoring abilities.

Alfred Binet and the psychology of testimony

In the early 1890s, Alfred Binet (1857-1911) became one of the most famous specialists in the study of human memory. He conducted research on many different aspects of memory and was a pioneer (1) in the study of the influence of suggestions (1894) on memory and the whole question of what would nowadays be called false memory or memory illusions, and (2) in founding the science of testimony (1900) by examining the influence of suggestion on memory but also its distortions. It was first within the framework of his program of individual psychology that Binet engaged in research that would lead to the idea of the foundation of this new field of research. In his book "on suggestibility" (1900), Binet formally established the scientific foundation for a "Science of testimony", studying the effect of suggestibility with images as stimuli. Inspired by Binet's experimental investigations, Stern (1902) had the talent to bring to light this process of natural falsification of memory. He outlined the plan and the limits of the new field of research glimpsed by Binet, he systematized its methods and procedures, he specified the points to be researched, and he finally gave a personal example of how the experiment should be conducted. Stern's work showing that error-free recollection is not the rule but the exception was the starting point of a movement that clearly attracted the world of German psychologists and jurists, and soon psychologists and jurists from various countries.

Absolute pitch is disrupted by a memory illusion.

An experiment is reported, showing that short-term memory for pitch in absolute pitch (AP) possessors, while substantially more accurate than in AP nonpossessors, is also subject to illusory conjunctions of pitch and time and so can be distorted or enhanced by a single tone embedded in a sequence of six other tones. Both AP possessors and AP nonpossessors performed a short-term memory task. A test tone was presented, then a sequence of six intervening tones, and then a probe tone. The test and probe tones either were identical in pitch or differed by a semitone. The AP nonpossessors judged whether the test and probe tones were the same or different, and the AP possessors identified the test and probe tones by name. In some conditions, a tone of identical pitch to the probe tone or an octave removed from this tone was included in the intervening sequence. In both the AP possessors and AP nonpossessors, this illusion-producing tone increased judgments that the test and probe tones were identical. These results accord with a model of the system underlying short-term memory for pitch proposed earlier and show that this system is bidimensional in nature, involving both pitch height and pitch class.

Memory illusions and category malleability: False recognition for goal-derived reorganizations of common categories.

Four studies explore semantic memory intrusions for goal-derived subcategories (e.g., "sports good for backache") embedded in taxonomic categories (e.g., "sports"). Study 1 presented hybrid lists (composed of typical items from both representations: taxonomic categories and subcategories) together with names of subcategories, names of taxonomic categories, or with no names. Subcategory names produced levels of false recognitions for critical lures from subcategories comparable with critical lures from taxonomic categories. Study 2 presented lists of exemplars either from taxonomic categories or subcategories (between participants). Lists of subcategories paired with their names produced higher levels of false recognition for subcategories lures compared with taxonomic lures. Study 3 replicated this result and showed that even though distinctiveness of taxonomic lures in a subcategory context (i.e., subcategory list with a subcategory name) may facilitate rejection of these lures, subcategory lures were still more falsely recognized than were taxonomic lures when retrieval monitoring was hindered through speeded recognition. Study 4 replicated the results with lists in which production frequency was better controlled and with a larger sample allowing for increased power of the test. Although confirming the critical role of preexistent categorical structures in the generation of false memories, results show that false memories for goal-derived subcategories can occur with the same frequency as false memories stemming from better established taxonomic categories. Such results broaden the scope of occurrence of false memories to goal-derived semantic organizations, which are often closer to categorizations used in real-world environments.

Δ9-Tetrahydrocannabinol During Encoding Impairs Perceptual Details yet Spares Context Effects on Episodic Memory

BackgroundWith the growing acceptance of cannabis use, it is crucial to understand the drug’s effects on episodic memory accuracy and distortion. We investigated the impact of the administration of Δ9-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, on a context-based memory illusion. MethodsIn a double-blind, placebo-controlled, within-subjects design, healthy infrequent cannabis users (N = 24) memorized object pictures that were superimposed over scenes (e.g., gray cat on beach) after pretreatment with placebo or THC (15 mg oral). Two days later under sober conditions, memory for the object pictures was tested by asking participants to discriminate between previously seen objects or perceptually similar lures (e.g., different gray cat). Context reinstatement was manipulated by presenting objects on their original or different scenes (e.g., beach or forest). ResultsTHC impaired memory for perceptual details of objects compared with placebo, and the context illusion was obtained in each condition: context reinstatement increased high-confidence false recognition along with correct recognition of previously seen objects. Although THC did not interact with these context effects overall, post hoc analyses showed that THC magnified the context illusion when objects were semantically congruent with their encoding contexts but abolished the context illusion when objects were incongruent with their encoding contexts. ConclusionsThese results are consistent with the hypothesis that THC impairs the encoding of specific object information more than item-context associations. As a result, THC may spare the distorting effects of context reinstatement on memory. In fact, THC may increase these distorting effects under conditions when objects are semantically congruent with context.

The neural mechanism of fluency-based memory illusions: the role of fluency context.

Recognition memory judgments can be influenced by a variety of signals including fluency. Here, we investigated whether the neural correlates of memory illusions (i.e., misattribution of fluency to prior study) can be modulated by fluency context. Using a masked priming/recognition memory paradigm, we found memory illusions for low confidence decisions. When fluency varied randomly across trials, we found reductions in perirhinal cortex (PrC) activity for primed trials, as well as a (pre)cuneus-PrC (BA 35) connectivity. When the fluency context was unchanging, there was increased PrC activity for primed trials, with the (pre)cuneus showing greater connectivity with PrC (BA 36). Thus, our results tentatively suggest two neural mechanisms via which fluency can lead to memory illusions.

Ошибочное опознание изображения типичного представителя класса как проявление категориальной иллюзии памяти

Ошибочное опознание изображения типичного представителя класса как проявление категориальной иллюзии памяти

Transfer appropriate fluency: Encoding and retrieval interactions in fluency-based memory illusions.

Stimuli that are fluently processed are more likely to be called "old" on a recognition memory test compared with less fluently processed stimuli. The goal of the current study was to investigate how the perceived diagnostic value of fluency is affected by a match between encoding and test conditions. During the encoding phase, participants engaged in different tasks designed to reflect different phonological processing requirements. On a later recognition test, the phonological fluency of some of the items was enhanced. The results showed a relationship between the degree of phonological processing carried out during encoding and the degree to which phonological fluency affected recognition memory decisions. Moreover, when both encoding and fluency conditions were manipulated, there was an encoding by retrieval interaction. When the encoding phase involved attending to visual features, perceptual fluency had a larger effect on recognition responses than phonological fluency. Likewise, when encoding focused on phonological features, phonological fluency had a larger influence on recognition than perceptual fluency. Collectively, the results show that fluency-based illusions of recognition memory recognition biases are more likely when there is a match in the attributes emphasized during study and test. (PsycINFO Database Record

Picture (im)perfect: Illusions of recognition memory produced by photographs at test.

Photographs have been found to affect a variety of psychological judgments. For example, nonprobative but semantically related photographs may increase beliefs in the truth of general knowledge statements (Newman, Garry, Bernstein, Kantner, & Lindsay, Psychonomic Bulletin & Review, 19(5), 969-974, 2012; Newman et al., Journal of Experimental Psychology: Learning, Memory, and Cognition, 41(5), 1337-1348, 2015). Photographs can also create illusions of memory (Cardwell, Henkel, Garry, Newman, & Foster, Memory & Cognition, 44(6), 883-896, 2016; Henkel, Applied Cognitive Psychology, 25(1), 78-86, 2011; Henkel & Carbuto, 2008). A candidate mechanism for these effects is that a photograph increases the fluency with which a statement or an event is processed. The present study was conducted to determine whether photos at test can induce illusions of recognition memory and to test the viability of a conceptual fluency explanation of these effects. The results of the present study suggest that photographs enhance the fluency of related words (Experiment 1), that false memories can be produced by the mere presence of a related photo on a recognition memory test for words (Experiments 2 & 3), and that these effects appear to be limited to conceptually based recognition tests (Experiments 4 & 5). The results support the notion that photograph-based illusions of memory stem from the ability of related photographs to increase the speed and ease of conceptual processing.

The Dark Side of Context: Context Reinstatement Can Distort Memory

It is widely assumed that context reinstatement benefits memory, but our experiments revealed that context reinstatement can systematically distort memory. Participants viewed pictures of objects superimposed over scenes, and we later tested their ability to differentiate these old objects from similar new objects. Context reinstatement was manipulated by presenting objects on the reinstated or switched scene at test. Not only did context reinstatement increase correct recognition of old objects, but it also consistently increased incorrect recognition of similar objects as old ones. This false recognition effect was robust, as it was found in several experiments, occurred after both immediate and delayed testing, and persisted with high confidence even after participants were warned to avoid the distorting effects of context. To explain this memory illusion, we propose that context reinstatement increases the likelihood of confusing conceptual and perceptual information, potentially in medial temporal brain regions that integrate this information.

Complementarity in false memory illusions.

For some years, the DRM illusion has been the most widely studied form of false memory. The consensus theoretical interpretation is that the illusion is a reality reversal, in which certain new words (critical distractors) are remembered as though they are old list words rather than as what they are-new words that are similar to old ones. This reality-reversal interpretation is supported by compelling lines of evidence, but prior experiments are limited by the fact that their memory tests only asked whether test items were old. We removed that limitation by also asking whether test items were new-similar. This more comprehensive methodology revealed that list words and critical distractors are remembered quite differently. Memory for list words is compensatory: They are remembered as old at high rates and remembered as new-similar at very low rates. In contrast, memory for critical distractors is complementary: They are remembered as both old and new-similar at high rates, which means that the DRM procedure induces a complementarity illusion rather than a reality reversal. The conjoint recognition model explains complementarity as a function of three retrieval processes (semantic familiarity, target recollection, and context recollection), and it predicts that complementarity can be driven up or down by varying the mix of those processes. Our experiments generated data on that prediction and introduced a convenient statistic, the complementarity ratio, which measures (a) the level of complementarity in memory performance and (b) whether its direction is reality-consistent or reality-reversed. (PsycINFO Database Record

Ad hoc categories and false memories: Memory illusions for categories created on-the-spot.

Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment 1 revealed considerable levels of false recognitions of critical words from ad hoc categories. False recognitions occurred even when the lists were presented without an organizing theme (i.e., the category's label). Experiments 1 and 2 tested whether (a) the ease of identifying the categories' themes, and (b) the lists' backward associative strength could be driving the effect. List identifiability did not correlate with false recognition, and the effect remained even when backward associative strength was controlled for. Experiment 3 manipulated the distractor items in the recognition task to address the hypothesis that the salience of unrelated items could be facilitating the occurrence of the phenomenon. The effect remained when controlling for this source of facilitation. These results have implications for assumptions made by theories of false memories, namely the preexistence of associations in the activation-monitoring framework and the central role of gist extraction in fuzzy-trace theory, while providing evidence of the occurrence of false memories for more dynamic and context-dependent knowledge structures. (PsycINFO Database Record

The processing of semantic relatedness in the brain: Evidence from associative and categorical false recognition effects following transcranial direct current stimulation of the left anterior temporal lobe

A dominant view of the role of the anterior temporal lobe (ATL) in semantic memory is that it serves as an integration hub, specialized in the processing of semantic relatedness by way of mechanisms that bind together information from different brain areas to form coherent amodal representations of concepts. Two recent experiments, using brain stimulation techniques along with the Deese–Roediger–McDermott (DRM) paradigm, have found a consistent false memory reduction effect following stimulation of the ATL, pointing to the importance of the ATL in semantic/conceptual processing. To more precisely identify the specific process being involved, we conducted a DRM experiment in which transcranial direct current stimulation (anode/cathode/sham) was applied over the participants' left ATL during the study of lists of words that were associatively related to their non-presented critical words (e.g., rotten, worm, red, tree, liqueur, unripe, cake, food, eden, peel, for the critical item apple) or categorically related (e.g., pear, banana, peach, orange, cantaloupe, watermelon, strawberry, cherry, kiwi, plum, for the same critical item apple). The results showed that correct recognition was not affected by stimulation. However, an interaction between stimulation condition and type of relation for false memories was found, explained by a significant false recognition reduction effect in the anodal condition for associative lists that was not observed for categorical lists. Results are congruent with previous findings and, more importantly, they help to clarify the nature and locus of false memory reduction effects, suggesting a differential role of the left ATL, and providing critical evidence for understanding the creation of semantic relatedness-based memory illusions.

Maltreatment increases spontaneous false memories but decreases suggestion-induced false memories in children.

We examined the creation of spontaneous and suggestion‐induced false memories in maltreated and non‐maltreated children. Maltreated and non‐maltreated children were involved in a Deese–Roediger–McDermott false memory paradigm where they studied and remembered negative and neutral word lists. Suggestion‐induced false memories were created using a misinformation procedure during which both maltreated and non‐maltreated children viewed a negative video (i.e., bank robbery) and later received suggestive misinformation concerning the event. Our results showed that maltreated children had higher levels of spontaneous negative false memories but lower levels of suggestion‐induced false memories as compared to non‐maltreated children. Collectively, our study demonstrates that maltreatment both increases and decreases susceptibility to memory illusions depending on the type of false memory being induced. Statement of contribution What is already known on this subject? Trauma affects memory.It is unclear how trauma affects false memory. What does this study add? This study focuses on two types of false memories.