Related Lures Research Articles

Phantom Recollection of Bridging and Elaborative Inferences

The phantom recollection model is a multiprocess analysis according to which memory judgments are collaboratively supported by one's recollection of an item in its context, a vaguer sense of stimulus familiarity, and the phantom recollection of the substance and even perceptual details of unstudied but related lures. Phantom recollection has previously been documented to support readers’ judgments of certain logical implications of sentences and discourse bridging inferences. This study evaluated the representational status of elaborative inferences in a comparable way. Subjects read blocks of brief passages and then judged explicit, bridging inference, elaborative inference, and control test items. Different subject groups were instructed to make their judgments with (1) a verbatim criterion, or (2) a gist criterion or (3) to accept only items implied but not stated in their passages. Multinomial tree processing analysis was applied to the data. Consistent with numerous other behavioral measures, these procedures provided evidence of phantom recollection support for bridging but not elaborative inferences. This outcome bears on the representational basis of elaborative inferences. The merits but also some hazards of the present methodology are discussed.

Misremembering what you see or hear: Dissociable effects of modality on short- and long-term false recognition.

False working memories readily emerge using a visual item-recognition variant of the converging associates task. Two experiments, manipulating study and test modality, extended prior working memory results by demonstrating a reliable false recognition effect (more false alarms to associatively related lures than to unrelated lures) within seconds of encoding in either the visual or auditory modality. However, false memories were nearly twice as frequent when study lists were seen than when they were heard, regardless of test modality, although study-test modality mismatch was generally disadvantageous (consistent with encoding specificity). A final experiment that varied study-test modality using a hybrid short- and long-term memory test (Flegal, Atkins & Reuter-Lorenz, 2010) replicated the auditory advantage in the short term but revealed a reversal in the long term: The false memory effect was greater in the auditory study-test condition than in the visual study-test condition. Thus, the same encoding conditions gave rise to an opposite modality advantage depending on whether recognition was tested under short-term or long-term memory conditions. Although demonstrating continuity in associative processing across delay, the results indicate that delay condition affects the availability of modality-dependent features of the memory trace and, thus, distinctiveness, leading to dissociable patterns of short- and long-term memory performance.

Young children produce categorical false recall without activation of the lure items

AbstractIndividuals who study a list of words that are all related to another word that is not presented (a lure word) sometimes produce a false memory of having studied the lure word. The false memories are observed in lists of words that are in the same category as (category list) or associated with (associative list) a word that was not presented in an attempt to elicit false recall. The present study investigated whether young children create these types of false recall. Following the study of a categorical list, false recall was elicited in young children to the same degree as in adults, but studying an associative list elicited false recall only in adults. Furthermore, categorically related lure words did not have a priming effect in young children. These results suggest that the categorical false recall is produced via a different mechanism from the associative false recall.

Prospective memory and aging: Evidence for preserved spontaneous retrieval with exact but not related cues.

We examined whether normal aging spares or compromises cue-driven spontaneous retrieval processes that support prospective remembering. In Experiment 1, young and older adults performed prospective-memory tasks that required either strategic monitoring processes for retrieval (nonfocal) or for which participants relied on spontaneous retrieval processes (focal). We found age differences for nonfocal, but not focal, prospective-memory performance. Experiments 2 and 3 used an intention-interference paradigm in which participants were asked to perform a prospective-memory task (e.g., press "Q" when the word money appears) in the context of an image-rating task and were then told to suspend their prospective-memory intention until after completing an intervening lexical-decision task. During the lexical-decision task, we presented the exact prospective-memory cue (e.g., money; Experiments 2 and 3) or a semantically related lure (e.g., wallet; Experiment 3), and we inferred spontaneous retrieval from slowed lexical-decision responses to these items relative to matched control items. Young and older adults showed significant slowing when the exact prospective-memory cue was presented. Only young adults, however, showed significant slowing to the semantically related lure items. Collectively, these results partially support the multiprocess theory prediction that aging spares spontaneous retrieval processes. Spontaneous retrieval processes may become less sensitive with aging, such that older adults are less likely to respond to cues that do not exactly match their encoded targets.

Amnesiacs might get the gist: Reduced false recognition in amnesia may be the result of impaired item-specific memory

It is a common finding in tests of false recognition that amnesic patients recognize fewer related lures than healthy controls, and this has led to assumptions that gist memory is damaged in these patients (Schacter, Verfaellie, & Anes, 1997, Neuropsychology, 11; Schacter, Verfaellie, Anes, & Racine, 1998, Journal of Cognitive Neuroscience, 10; Schacter, Verfaellie, & Pradere, 1996, Journal of Memory and Language, 35). However, clinical observations find that amnesic patients typically hold meaningful conversations and make relevant remarks, and there is some experimental evidence highlighting preserved immediate recall of prose (Baddeley & Wilson, 2002, Neuropsychologia, 40; Gooding, Isaac, & Mayes, 2005, Neuropsychologia, 43; Rosenbaum, Gilboa, Levine, Winocur, & Moscovitch, 2009, Neuropsychologia, 47), which suggests that amnesiacs can get the gist. The present experiment used false recognition paradigms to assess whether the reduced rate of false recognition found in amnesic patients may be a consequence of their impaired item-specific memory. It examined the effect of increasing the item-specific memory of amnesic patient DA by bringing her to criterion on relevant study-lists and compared her performance on a false recognition paradigm with a group of 32 healthy young adults. Results indicated that when DA’s item-specific memory was increased she was more able to gist and her performance was no different to the healthy young adults. Previous assumptions that gist memory is necessarily damaged in amnesia might therefore be revisited, since the reduced rate of false recognition could be caused by impaired item-specific memory. The experiment also highlights a positive relationship between item-specific and gist memory which has not previously been accounted for in false-recognition experiments.

Semantic and phonological information in sentence recall: Converging psycholinguistic and neuropsychological evidence

We present one experiment and a neuropsychological case study to investigate to what extent phonological and semantic representations contribute to short-term sentence recall. We modified Potter and Lombardi's (1990) intrusion paradigm, in which retention of a list interferes with sentence recall such that on the list a semantically related lure is presented, which is expected to intrude into sentence recall. In our version, lure words are either semantically related to target words in the sentence or semantically plus phonologically related. With healthy participants, intrusions are more frequent when lure and target overlap phonologically in addition to semantically than when they solely overlap semantically. When this paradigm is applied to a patient with a phonological short-term memory impairment, both lure types induce the same amount of intrusions. These findings indicate that usually phonological information is retained in sentence recall in addition to semantic information.

Word-frequency effects in long-term semantic priming and false memory

Several studies have used the lexical decision task (LDT) with the Deese-Roediger-McDermott (DRM) false-memory paradigm to investigate whether long-term semantic priming (LTSP) occurs following presentation of lists of items (e.g., bed, dream, snore) for related non-presented lure words (e.g., sleep). However, results have been mixed, with some studies observing priming, whilst others have not. The present study had four goals: (i) to investigate the existence of LTSP in the LDT; (ii) to investigate effects of LTSP on standard effects of word frequency on LDT performance; (iii) to investigate the effect, if any, of word frequency on true and false recall; and (iv) to compare LDT performance with performance on a subsequent free-recall task. The findings showed (i) a significant effect of LTSP on LDT performance; (ii) no effect of LTSP on standard effects of word frequency on LDT performance; (iii) no effect of word frequency on either true or false free recall; and (iv) a significant relationship between LDT and free-recall performance. Implications of these findings for understanding LTSP and false memories are discussed.

Neural mechanisms of semantic interference and false recognition in short-term memory

Decades of research using the Deese–Roediger–McDermott (DRM) paradigm have demonstrated that episodic memory is vulnerable to semantic distortion, and neuroimaging investigations of this phenomenon have shown dissociations between the neural mechanisms subserving true and false retrieval from long-term memory. Recently, false short-term memories have also been demonstrated, with false recognition of items related in meaning to memoranda encoded less than 5s earlier. Semantic interference is also evident in short-term memory, such that correct rejection of related lures is slowed relative to correct rejection of unrelated lures. The present research constitutes the first fMRI investigation of false recognition and semantic interference in short-term memory using a short-term DRM paradigm in which participants retained 4 semantic associates over a short 4-s filled retention interval. Results showed increased activation in the left mid-ventrolateral prefrontal cortex (BA45) associated with semantic interference, and significant correlations between these increases and behavioral measures of interference across subjects. Furthermore, increases in dorsolateral PFC occurred when related lures were correctly rejected versus falsely remembered. Compared with false recognition, true recognition was associated with increases in left fusiform gyrus, a finding consistent with the notion that increased perceptual processing may distinguish true from false recognition over both short and long retention intervals. Findings are discussed in relation to current models of interference resolution in short-term memory, and suggest that false short-term recognition occurs as a consequence of the failure of frontally mediated cognitive control processes which adjudicate semantic familiarity in support of accurate mnemonic retrieval.

How hippocampus and cortex contribute to recognition memory: revisiting the complementary learning systems model.

We describe how the Complementary Learning Systems neural network model of recognition memory (Norman and O'Reilly (2003) Psychol Rev 104:611-646) can shed light on current debates regarding hippocampal and cortical contributions to recognition memory. We review simulation results illustrating three critical differences in how (according to the model) hippocampus and cortex contribute to recognition memory, all of which derive from the hippocampus' use of pattern separated representations. Pattern separation makes the hippocampus especially well-suited for discriminating between studied items and related lures; it makes the hippocampus especially poorly suited for computing global match; and it imbues the hippocampal ROC curve with a Y-intercept > 0. We also describe a key boundary condition on these differences: When the average level of similarity between items in an experiment is very high, hippocampal pattern separation can fail, at which point the hippocampal model will start to behave like the cortical model. We describe the implications of these simulation results for extant debates over how to describe hippocampal versus cortical contributions and how to measure these contributions.

The inverse list length effect: A challenge for pure exemplar models of recognition memory

When multiple items from a category are presented at study during a recognition memory procedure, false alarms to lures drawn from the same category increase. Distributed exemplar models of recognition assume that these effects occur because the representations of related lures are similar to the representations of studied items thus increasing the global matching strength of these items. We show that if list length is manipulated by keeping the number of categories constant, but increasing the number of exemplars in each category, then the unrelated false alarm rate decreases – thus inducing an inverse list length effect. Furthermore, if category structure is made less obvious by distributing items from a category through the list rather than presenting them in a blocked fashion the effect of length is less pronounced. This pattern suggests that it is subjects’ awareness of the categories on the list that is responsible for both related and unrelated false alarms. Simulations demonstrate that pure exemplar models such as the original version of the Retrieving Effectively from Memory model ( Shiffrin & Steyvers, 1997, REM) are not capable of accounting for the results. Rather a representation of the studied categories that subjects can use to reject unrelated lures must be formed. We show how a version of the Bind Cue Decide Model of Episodic Memory ( Dennis & Humphreys, 2001, BCDMEM) can account for the data using a category representation of this kind.

Listening for recollection: a multi-voxel pattern analysis of recognition memory retrieval strategies

Recent studies of recognition memory indicate that subjects can strategically vary how much they rely on recollection of specific details vs. feelings of familiarity when making recognition judgments. One possible explanation of these results is that subjects can establish an internally directed attentional state (“listening for recollection”) that enhances retrieval of studied details; fluctuations in this attentional state over time should be associated with fluctuations in subjects’ recognition behavior. In this study, we used multi-voxel pattern analysis of fMRI data to identify brain regions that are involved in listening for recollection. We looked for brain regions that met the following criteria: (1) Distinct neural patterns should be present when subjects are instructed to rely on recollection vs. familiarity, and (2) fluctuations in these neural patterns should be related to recognition behavior in the manner predicted by dual-process theories of recognition: Specifically, the presence of the recollection pattern during the pre-stimulus interval (indicating that subjects are “listening for recollection” at that moment) should be associated with a selective decrease in false alarms to related lures. We found that pre-stimulus activity in the right supramarginal gyrus met all of these criteria, suggesting that this region proactively establishes an internally directed attentional state that fosters recollection. We also found other regions (e.g., left middle temporal gyrus) where the pattern of neural activity was related to subjects’ responding to related lures after stimulus onset (but not before), suggesting that these regions implement processes that are engaged in a reactive fashion to boost recollection.

Altered Prefrontal and Hippocampal Function During Verbal Encoding and Recognition in People With Prodromal Symptoms of Psychosis

Despite robust evidence of hippocampal abnormalities in schizophrenia, it is unclear whether hippocampal dysfunction predates the onset of psychosis. We used functional magnetic resonance imaging to investigate hippocampal function in subjects with an at-risk mental state (ARMS). Eighteen subjects meeting criteria for an ARMS and 22 healthy controls, matched for age, gender, and premorbid IQ, were scanned while performing a version of the Deese-Roediger-McDermott false memory task. During an encoding phase, subjects read lists of words aloud. Following a delay, they were presented with 24 target words, 24 semantically related lure words, and 24 novel words and required to indicate if each had been presented before. Behaviorally, the ARMS group made more false alarm responses for novel words than controls (P = .04) and had a lower discrimination accuracy for target words (P = .02). During encoding, ARMS subjects showed less activation than healthy controls in the left middle frontal gyrus, the bilateral medial frontal gyri, and the left parahippocampal gyrus. Correct recognition relative to false alarms was associated with differential engagement of the hippocampus bilaterally in healthy controls, but this difference was absent in the ARMS group. The ARMS was associated with altered function in the medial temporal cortex, as well as in the prefrontal regions, during both verbal encoding and recognition. These neurofunctional differences were associated with diminished recognition performance and may reflect the greatly increased risk of psychosis associated with the ARMS.

Implicit false memory in the DRM paradigm: Effects of amnesia, encoding instructions, and encoding duration.

Recent studies with the Deese/Roediger-McDermott (Deese 1959; Roediger & McDermott, 1995) paradigm have revealed that amnesic patients do not only show impaired veridical memory, but also diminished false memory for semantically related lure words. Due to the typically used explicit retrieval instructions, however, this finding may reflect problems at encoding, at recollection, or both. Therefore, the present experiments examined implicit as well as explicit false memory in patients suffering from Korsakoff's syndrome and controls. In Experiment 1, encoding instructions either focused on remembering individual list words, or on discovering semantic relationships among the words. In Experiment 2, different presentation durations were used. Results emphasize the distinction between automatic and intentional retrieval: Korsakoff patients' veridical and false memory scores were diminished when explicit recollection was required, but not when memory was tested implicitly. Encoding manipulations only significantly affected veridical memory: Priming was reduced with thematic encoding, and explicit retrieval was facilitated when given more study time.

The role of metacognitive knowledge in recollection rejection

Recollection rejection is a memory editing mechanism in which related lures are rejected because of the recollection of the lure's instantiating target (e.g., "I know it wasn't pretty because it was beautiful"). According to one view, recollection rejection requires an assumption on the part of the participant that both a word and its related lure could not have been studied. We examined this view by manipulating the instructions that were given to participants (Experiment 1) and the nature of the study list (Experiment 2). Estimates of recollection rejection derived from the phantom receive operating characteristic model found evidence for the role of metacognitive assumptions, but only when metacognitive knowledge was manipulated by varying the nature of the study list.

Pictorial encoding effects and memory confusions in the Deese–Roediger–McDermott paradigm: Evidence for the activation of spontaneous imagery

The purpose of the experiments reported in this paper was to examine the possible role of spontaneous imagery and list-specific cues on pictorial encoding effects induced by the Deese-Roediger-McDermott (DRM) task. After viewing pictures and words referring to thematically related materials, by way of a picture/word source-judgement task, participants were asked to remember the way in which these materials were presented. Participants reported “seeing” pictures of items that were presented as words, an effect predicted by the imaginal activation hypothesis in its suggestion that incidental images experienced during encoding will later be mistaken as memories for pictures. Whether participants made the same picture misattributions on related lures (or non-presented related items) depended on the way in which the lures’ respective thematic lists were experienced during encoding (Experiments 1 and 2), pointing to the effects of list-specific cues in picture/word judgements. These findings have intriguing implications for interpretations of picture-encoding effects induced by the DRM task. The findings also speak to the use of DRM false-memory rates when marshalling evidence against the use of imagery in applied settings.

Neurodevelopmental Correlates of True and False Recognition

The Deese/Roediger–McDermott (DRM) false-memory effect has been extensively documented in psychological research. People falsely recognize critical lures or nonstudied items that are semantically associated with studied items. Behavioral research has provided evidence for age-related increases in the DRM false-recognition effect. The present event-related functional magnetic resonance imaging study was aimed at investigating neurodevelopmental changes in brain regions associated with true- and false-memory recognition in 8-year olds, 12-year olds, and adults. Relative to 8-year olds, adults correctly endorsed more studied items as “old” but also mistakenly endorsed more critical lures. Age-related increases in recollection were associated with changes in the medial temporal lobe (MTL) activation profile. Additionally, age-related increases in false alarms (FAs) to semantically related lures were associated with changes in the activation profile of left ventrolateral prefrontal cortex, a region associated with semantic processing. Additional regions exhibiting age-related changes include posterior parietal and anterior prefrontal cortices. In summary, concomitant changes in the MTL, prefrontal cortex, and parietal cortex underlie developmental increases in true and false recognition during childhood and adolescence.

False working memories? Semantic distortion in a mere 4 seconds

False memories are well-established, episodic memory phenomena: Semantically related associates are confidently and erroneously remembered as studied items. We report four experiments yielding similar effects in a working memory paradigm. Four semantically related words were retained over a brief interval. Whether or not the interval was filled with a math verification task, semantically related lures were mistakenly recognized as members of the memory set and took longer to reject than did unrelated negative probes. In a short-term recall task, semantic intrusions exceeded other errors (e.g., phonemic). Our results demonstrate false memory effects for a subspan list when a mere 4 sec was given between study and test. Such rapid semantic errors presumably result from associative processing, may be related to familiarity-based proactive interference in working memory, and are consistent with recent models that integrate short- and long-term memory processes.

Neural correlates of memory confidence

The present study aimed to shed light on the neural underpinnings of high vs. low memory confidence. To dissociate memory confidence from accuracy, the Deese–Roediger McDermott (DRM) paradigm was employed, which – compared to other memory paradigms – elicits a rather evenly distributed number of high-confident responses across all possible combinations of memory response types (i.e., hits, false alarms, correct rejections, and misses). In the standard DRM procedure, subjects are first presented with thematically interrelated word lists at encoding, which at recognition are intermixed with related and unrelated distractor items. The signature of a false memory or DRM effect is an increased number of high-confident false memories, particularly for strongly related lure items. For the present study, 17 female subjects were administered a verbal DRM task, whereas neural activation was indexed by fMRI. The behavioral analyses confirmed the expected false memory effect: subjects made more high-confident old responses (both hits and false alarms) the closer the items were related to the central list theme. Across all four memory response types, an increase in confidence at recognition was associated with bilateral activation in the anterior and posterior cingulate cortex along with medial temporal regions. In contrast, increments in doubt were solely related to activation in the superior posterior parietal cortex. To conclude, the study provides some evidence for dissociable systems for confidence and doubt.

Phantom ROC: Recollection rejection in a hybrid conjoint recognition signal detection model

The present experiments test predictions of dual process models with regards to recollection rejection using a model called phantom ROC. Participants studied pictures and then took a recognition test in which they were presented with targets (i.e., the exact picture presented), related lures (i.e., the same object but from a different angle), and unrelated lures (i.e., objects that had not been shown). For each item, participants answered both standard recognition and meaning recognition questions. In Experiment 1 participants studied pictures under either full attention or divided attention. In Experiment 2 some participants were told that no object was shown twice (i.e., mutual exclusivity instructions), while others were told that both camera angles might have been shown for some objects (no mutual exclusivity instructions). The present experiments provide three converging measures, all of which are consistent with dual process models that propose a recollection rejection mechanism.

On rejecting emotional lures created by phonological neighborhood activation.

The authors conducted 2 experiments to assess how phonologically related lures are rejected in a false memory paradigm. Some phonological lures were emotional (i.e., taboo) words, and others were not. The authors manipulated the presence of taboo items on the study list and reduced the ability to use controlled rejection strategies by dividing attention and forcing a short response deadline. The results converge on the idea that participants reduce false alarms to emotional lures by setting more stringent recognition criteria for these items based on their expected memorability. Additionally, emotional lures are less familiar than nonemotional lures because emotional lures have affective and semantic features that mismatch studied nonemotional items.