How similar is false recognition to veridical recognition objectively and subjectively?

Three recognition memory experiments were conducted using modified Deese-Roediger-McDermott (DRM) and DRM paradigms. In Experiment 1, the reaction time (RT) of the false alarms to critical nonpresented words (false memory) was compared with the RT of hits to the critical presented words and with the RT of hits to the studied list words (true memory). The RT of the false alarms to the critical nonpresented words was significantly longer than that of the hits to the critical words and than that of the studied list words. In Experiment 2, in addition to RT, participants' confidence level was measured on a 4-point scale for a yes or no response. Confidence rating was significantly higher for the hits to the critical presented words and to the list words than for the false alarms to the critical non-presented words. Experiment 3 further showed that how similar false memory experience was to that of true memory was a function of retention size (number of lists of words retained in memory). In all three experiments, the participants' recognition RTs distinguished false memory from veridical memory, and in Experiments 2 and 3, so did their confidence ratings. Therefore, false memory and veridical memory differ at both the objective and the subjective levels. The results are consistent with a single familiarity dimension model of recognition memory.     

The effect of warnings on false memories in young and older adults

In the present experiments, we examined adult age differences in the ability to suppress false memories, using the Deese-Roediger-McDermott (DRM) paradigm (Deese, 1959; Roediger & McDermott, 1995). Participants studied lists of words (e.g., bed, rest, awake, etc.), each related to a nonpresented critical lure word (e.g., sleep). Typically, recognition tests reveal false alarms to critical lures at rates comparable to those for hits for studied words. In two experiments, separate groups of young and older adults were unwarned about the false memory effect, warned before studying the lists, or warned after study and before test. Lists were presented at either a slow rate (4 sec/word) or a faster rate (2 sec/word). Young adults were better able to discriminate between studied words and critical lures when warned about the DRM effect either before study or after study but before retrieval, and their performance improved with a slower presentation rate. Older adults were able to discriminate between studied words and critical lures when given warnings before study, but not when given warnings after study but before retrieval. Performance on a working memory capacity measure predicted false recognition following study and retrieval warnings. The results suggest that effective use of warnings to reduce false memories is contingent on the quality and type of encoded information, as well as on whether that information is accessed at retrieval. Furthermore, discriminating between similar sources of activation is dependent on working memory capacity, which declines with advancing age.     

Remembering by the seat of your pants

According to dual-process theories of memory, "old" responses in recognition may reflect the separate or combined effects of two states, specific recollection and feelings of nonspecific familiarity. When decisions are based on familiarity, people may attribute enhanced perceptual fluency to memory for prior occurrence. In this experiment, we tested whether a subliminal somatic cue (a low-amplitude buzz) could enhance feelings of familiarity. The buzz increased the likelihood that participants responded "old," both correctly and incorrectly. This effect occurred only with subjectively difficult stimuli, those relatively unlikely to elicit clear recollection. When a stronger control buzz was used, the effect vanished. Results for confidence ratings were consistent with Whittlesea's SCAPE theory, producing a dissociation between hits and false alarms. Specifically, the buzz reduced confidence in hits and increased confidence in false alarms, in accord with the most likely attributions for the feelings of familiarity associated with the buzz.     

A mega recognition memory study of 2897 disyllabic words

Following the studies by Cortese, Khanna, and Hacker (2010) on recognition memory for monosyllabic words, recognition memory estimates (e.g., hits, false alarms, hits minus false alarms) for 3000 disyllabic words were obtained from 120 subjects and 2897 of these words were analysed via multiple regression. Participants studied 30 lists of 50 words and were tested on 30 lists of 100 words. Of the subjects, 60 received a constant study time of 2000?ms per item and 60 studied items at their own pace. Specific predictor variables included log word frequency, word length, imageability, age of acquisition, orthographic similarity, and phonological similarity. The results were similar to those of Cortese et al. (2010). Specifically, in the analysis of hits minus false alarms, the entire set of predictor variables accounted for 34.9% of the variance. All predictor variables except phonological similarity were related to performance, with imageability, length, orthographic similarity and frequency all being strong predictors. These results are mostly compatible with the predictions made by single- and dual-process theories. However, across items hit rates were not correlated with false alarms. Given that most variables produced the standard mirror pattern, this latter outcome poses a major challenge for recognition memory theories.     

The effects of word frequency and similarity on recognition judgments: the role of recollection

K. J. Malmberg, J. Holden, and R. M. Shiffrin (2004) reported more false alarms for low- than high-frequency words when the foils were similar to the targets. According to the source of activation confusion (SAC) model of memory, that pattern is based on recollection of an underspecified episodic trace rather than the error-prone familiarity process. The authors tested the SAC account by varying whether participants were warned about the nature of similar foils and whether the recognition test required the discrimination. More false alarms for low-frequency similar items occurred only when participants were not warned at study about the subtle features to be discriminated later. The differential false-alarm rate by word frequency corresponded to the pattern of remember responses obtained when the test instructions did not ask for a subtle discrimination, supporting the SAC account that reversed false-alarm rates to similar foils are based on the recollection process.     

Plasticity of prospective memory through a familiarization intervention in old adults

Younger adults consistently outperform older adults in laboratory prospective memory tasks. This study examines the effectiveness of an intervention that familiarizes older adults with the sequence of ongoing events to compensate their reduced prospective memory performance. We compared performance and electrophysiological measures of an intervention group (N = 20, 69-83 years) receiving a familiarization intervention to an individually matched control group (N = 20). As ongoing activity a 2-back working memory task was administered. Neural correlates were studied using event related potentials (ERPs) and source localization (standardized low-resolution brain electromagnetic tomography). Behavioural data showed faster reaction times in correct prospective trials and fewer prospective false alarms in the familiarization intervention group. ERP analyses displayed differential patterns for the two groups and source localization measures distinctively presented group differences in prospective memory trials with the control group recruiting more resources for a successful prospective memory performance. Together our data support the hypothesis that the familiarity with the sequence of ongoing events increases prospective memory performance and that this might be based on a higher efficiency of attentional monitoring resources and evaluation processes in the intervention group.     

Recollection rejection: how children edit their false memories.

A new methodology is presented for studying children's ability to suppress memory reports of false-but-gist-consistent events, one that measures children's use of a specific editing operation (recollection rejection) that suppresses false reports by accessing verbatim traces of true events. Children make memory reports under 2 instructional conditions, verbatim and gist, and the data are analyzed with fuzzy-trace theory's conjoint-recognition model. Application of the new methodology in studies of children's false memory for narrative events revealed that (a) false-memory editing increases dramatically between early and middle childhood, (b) even young children spontaneously edit their false memories, (c) measures of children's false-memory editing react appropriately to experimental manipulations, and (d) developmental reductions in the incidence of false-memory reports are primarily due to developmental improvements in verbatim memory ability (rather than to decreases in the formation of false memories). Implications for child forensic interviewing are discussed.     

Children's false memory and true disclosure in the face of repeated questions

The current study was designed to investigate children's memory and suggestibility for events differing in valence (positive or negative) and veracity (true or false). A total of 82 3- and 5-year-olds were asked repeated questions about true and false events, either in a grouped order (i.e., all questions about a certain event asked consecutively) or in a nongrouped order (i.e., questions about a certain event were interspersed with questions about other events). Interviewer gender was also varied. Individual differences, including attachment style, inhibition, and behavioral adjustment, were examined as potential predictors of memory and suggestibility. Results revealed significant age, valence, and veracity effects on children's memory reports. Path analysis demonstrated that individual differences in behavioral problems and inhibitory ability predicted children's provision of inaccurate information. Implications for psychological theory and legal application are discussed.     

The importance of seeing what is not there: A quasi‐signal detection analysis of positive and negative behavior in newlywed couples

Partners scrutinize each other's behaviors to identify the quality of their relationship. Because people's perception of their partners' behavior is imperfect, they face a signal detection problem for which there are 4 outcomes: hits, misses, false alarms, and correct rejections. Research confirms the importance of hits, misses, and false alarms for relationship quality, but nothing is known about correct rejections. In a prospective study among newlywed couples, it was predicted and found that people are good at detecting the absence of partner behavior, especially negative partner behavior, and that these correct rejections are important for relationship quality above and beyond hits. Happy partners see reality in a way that maintains their happiness, which includes seeing what is not there.     

“Are False Memories Permanent?”: An Investigation of the Long-Term Effects of Source Misattributions

With growing concerns over children's suggestibility and how it may impact their reliability as witnesses, there is increasing interest in determining the long-term effects of induced memories. The goal of the present research was to learn whether source misattributions found by Ceci, Huffman, Smith, and Loftus (1994) caused permanent memory alterations in the subjects tested. When 22 children from the original study were reinterviewed 2 years later, they recalled 77% of all true events. However, they only consented to 13% of all false events, compared to the 22% false consent rate (among the same subset of children) found by Ceci et al. (1994). Additionally, while children remained accurate in their recall of true events (they maintained assents 78% of the time), they “recanted” their earlier false consents 77% of the time, after the 2-year delay. Implications of these findings for child witnesses and the legal system are discussed.     

I Remember When You Taught Me That! Preschool Children's Memories of Realistic Learning Episodes

This study examined whether preschool children are able to identify the source of new knowledge that they acquired in a stimulating, interactive learning context. Sixty 4‐ to 5‐year‐old children participated in two staged learning events. Several days later, children were asked questions that assessed their knowledge of factual information presented during the events. Children indicated whether they knew the answer to each question and whether they remembered the moment they learned it (i.e. had an episodic memory of the learning event), and then recalled event details. A majority of preschoolers were able to accurately identify how they had learned at least some factual information, but this ability was not consistent across children and test items. Recall of event‐specific details was positively correlated with correct answers to factual questions. The results indicate that when preschool children are asked to reflect on past learning experiences that occurred in complex and realistic contexts, their source monitoring abilities are evident but not yet fully developed. Copyright © 2013 John Wiley & Sons, Ltd.     

The effects of repeating a recognition test in lorazepam-induced amnesia: Evidence for impaired contextual memory as a cause of amnesia

In two experiments, a recognition test for an earlier presented list was given twice in immediate succession (Test 1 and Test 2). On the hypothesis that anterograde amnesia for episodic memory involves a deficit in contextual memory, amnesic subjects should confuse familiarity with distractor items gained during Test 1 with familiarity gained during original list presentation. As a result, they should think that they recognize more items on Test 2. This will lower recognition efficiency in Test 2 by increasing false alarms rather than by reducing hits. For subjects with an amnesia induced by lorazepam, but not for control subjects, recognition efficiency was substantially reduced in Test 2 in both experiments. As predicted, this impairment was due to a large increase in false alarms, with no decrease in the number of hits. The impairment could not be explained by a difference in recognition level between lorazepam and control subjects on Test 1. These findings therefore support the contextual memory deficit hypothesis of anterograde amnesia. Their implications for understanding the relationship between recall and recognition in amnesia are discussed.     

Monitoring the future: object and source memory for real and imagined events

In these experiments a memory‐monitoring decision is made, whereby subjects must decide not only whether or not to‐be‐learned stimuli will be remembered—the focus of all of the past research into the Judgement of Learning (JOL)—but also whether they will be able to assess the source of those stimuli, as assessed by a new measure, Judgement of Source (JOS). In Experiment 1 subjects had to judge whether they would remember the occurrence and the source of items that were either seen or imagined. Although seen items were better remembered and sourced than imagined, subjects were unable to predict this outcome: they underestimated their ability to recall seen items and overestimated their ability to recall imagined items. In Experiment 2 subjects had to discriminate between self‐performed or other‐performed enacted or imagined events. We expected that the motor cues associated with overt performance should provide more sensory information than had the visual input in Experiment 1, and this should help subjects to discriminate between real and imagined items. As predicted, JOL magnitude showed that subjects were now able to predict accurately that they would recall more enacted events than imagined events. JOS magnitude showed that subjects incorrectly predicted that self‐enactment would assist source memory compared to imagination. However, it was the source of other‐focused events which was more accurately remembered. The results are discussed in terms of Koriat's (1997) view about cue utility in making JOLs. Copyright © 1999 John Wiley & Sons, Ltd.     

Blood glucose symptom beliefs of diabetic patients: accuracy and implications

Both diabetic patients and health care practitioners often assume that the subjective symptoms of extreme low and high blood glucose (BG) levels are easily recognized. This study tested the accuracy of BG symptom beliefs in a group of 26 insulin-dependent diabetic patients. A within-subject, repeated measures design was used to identify symptoms related to low and high glucose levels for individual subjects. On three occasions over a 1-year period, subjects completed symptom checklists just prior to 40 consecutive self-measurements of BG (an average of four times per day for 10 days). At the end of the year, subjects reported which symptoms they believed were related to their own low and high glucose levels. After determining whether each checklist item was empirically related to glucose levels and believed to relate to glucose levels, symptom beliefs were categorized as hits, false alarms, misses, or correct rejections. Across subjects, the frequency of accurate beliefs (hits and correct rejections) was higher than the frequency of inaccurate beliefs (false alarms and misses). Symptom belief accuracy differed greatly for individual subjects, however, and every subject had at least one inaccurate belief. False alarm beliefs were the more common type of error. Female subjects' symptom beliefs yielded more hits, as well as more false alarms. Males missed more symptoms, especially low BG symptoms, than females. Symptom belief accuracy was greater if symptom-glucose relationships remained stable across time.     

Externalizing psychopathology and behavioral disinhibition: working memory mediates signal discriminability and reinforcement moderates response bias in approach-avoidance learning

Research has suggested that reduced working memory capacity plays a key role in disinhibited patterns of behavior associated with externalizing psychopathology. In this study, participants (N = 365) completed 2 versions of a go/no-go mixed-incentive learning task that differed in the relative frequency of monetary rewards and punishments for correct and incorrect active-approach responses, respectively. Using separate structural equation models for conventional (hit and false alarm rates) and signal detection theory (signal discriminability and response bias) performance indices, distinct roles for working memory capacity and changes in payoff structure were found. Specifically, results showed that (a) working memory capacity mediated the effects of externalizing psychopathology on false alarms and discriminability of go versus no-go signals; (b) these effects were not moderated by the relative frequency of monetary rewards and punishments; (c) the relative frequency of monetary rewards and punishments moderated the effects of externalizing psychopathology on hits and response bias for go versus no-go responses; and (d) these effects were not mediated by working memory capacity. The findings implicate distinct roles for reduced working memory capacity and poorly modulated active approach and passive avoidance in the link between externalizing psychopathology and behavioral disinhibition.     

Study of behavioural and neural bases of visuo‐spatial working memory with an fMRI paradigm based on an n‐back task

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language‐free adaptation of a 2‐back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM‐based random effects procedures and t‐tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self‐corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non‐clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block‐design paradigms.     

False memory in a short-term memory task

The Deese/Roediger-McDermott (DRM; Roediger & McDermott, 1995) paradigm reliably elicits false memories for critical nonpresented words in recognition tasks. The present studies used a Sternberg (1966) task with DRM lists to determine whether false memories occur in short-term memory tasks and to assess the contribution of latency data in the measurement of false memories. Subjects studied three, five, or seven items from DRM lists and responded to a single probe (studied or nonstudied). In both experiments, critical lures were falsely recognized more often than nonpresented weak associates. Latency data indicated that correct rejections of critical lures were slower than correct rejections of weakly related items at all set sizes. False alarms to critical lures were slower than hits to list items. Latency data can distinguish veridical and false memories in a short-term memory task. Results are discussed in terms of activation-monitoring models of false memory.     

Biography becomes autobiography: distorting the subjective past

This work addresses whether creating a biographical sketch for a fictional adolescent can increase confidence that one personally experienced these details in adolescence (memory distortion) and whether susceptibility to such distortion (depends on whether adolescence is considered part of one's subjective past or subjective present. We divided the subjective past and present using the point at which a person experienced the last life event that changed his or her personality significantly. We operationalized the subjective past as events associated with the period before the last life-changing event and the subjective present as events associated with the period after that event. Participants' confidence in their own autobiographical memory increased after they wrote a brief story about a fictional character. This increase occurred only for those who considered adolescence to be part of their subjective past. These results indicate that subjective time (in addition to objective time) may be a valuable factor in determining who is susceptible to memory distortion. We discuss these findings in terms of familiarity attribution and source monitoring.