Source Memory Deficits Research Articles

Impaired cognitive performance in older adults is associated with deficits in item memory and memory for object features

Amnestic mild cognitive impairment (aMCI) is associated with damage to the perirhinal/entorhinal cortex, and consequently, deficits in item/object memory. However, cognitive assessments commonly used to identify individuals with aMCI require a clinician to administer and interpret the test. We developed a novel self-administered global cognitive assessment, called the Cognitive Assessment via Keyboard (CAKe). To assess the relationship between CAKe performance and perirhinal/entorhinal cortex-dependent memory function, participants completed the CAKe, a feature source memory task, and a context memory task. During the memory tasks, participants studied line drawings with either a green or orange internal color (feature memory runs) or external color (context memory runs) and then classified each item as old and previously presented with a “green” or “orange” color, or “new”. CAKe scores were correlated with item memory accuracies and source memory accuracies on both tasks. Participants with ‘impaired’ CAKe performance had worse item memory and worse feature source memory accuracies than those with ‘normal’ CAKe performance. These results demonstrate specific deficits in item memory and feature source memory and suggest that our assessments may be a valid predictor of aMCI memory deficits.

The misidentification syndromes and source memory deficits with their neuroanatomical correlates from neuropsychological perspective

Abstract The suggested model is discussed with reference to two clinical populations with memory disorders – patients with misidentification syndromes and those with source memory impairment, both of whom may present with (broadly conceived) déjà vu phenomenon, without insight into false feeling of familiarity. The role of the anterior thalamic nucleus and retrosplenial cortex for autobiographical memory and familiarity is highlighted.

Intent matters: Resolving the intentional versus incidental learning paradox in episodic long-term memory.

Decades of research have established that the intent to remember information has no effect on episodic long-term memory. This claim, which is routinely taught in introductory cognitive psychology courses, is based entirely on pure-list between-subjects designs in which memory performance is equal for intentional and incidental learning groups. In the current 11 experiments, participants made semantic judgements about each word in a list but they had to remember only words presented in a specific color. We demonstrate that in such mixed-list designs there is a substantial difference between intentionally and incidentally learned items. The first four experiments show that this finding is independent of the remember cue onset relative to the semantic judgment. The remaining seven experiments test alternative explanations as to why intent only matters in mixed-list designs but not in pure-list designs-inhibition of incidentally learned items, output interference, selective relational encoding, or selective threshold-shifting. We found substantial support for the threshold-shifting account according to which the intent to remember boosts item-context associations in both mixed- and pure-list designs; however, in pure-list between-subjects designs, participants in the incidental learning group can use a lower retrieval threshold to compensate for the weaker memory traces. This led to more extralist intrusions in incidental learning groups; incidental learning groups also showed a source memory deficit. We conclude that intent always matters for long-term learning, but that the effect is masked in traditional between-subjects designs. Our results suggest that researchers need to rethink the role of intent in long-term memory. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Confabulations in a teenager with a right frontal hemispherotomy: Possible underlying mechanisms

Objective: Confabulations, i.e. false memories without intention to deceive, can be observed in adults with frontal brain damage. Confabulations are typically associated with episodic memory and/or executive disorders although the severity of these impairments is highly variable. Confabulations may also be associated with emotional/motivational particularities, as a positive bias seems to prevail in such situations. Several distinct cognitive and socio-affective processes may account for the various types of confabulations and these issues remain open. Method: We present the case of a teenager with an early acquired frontal damage, referred for “strange lies.” Besides a standard neuropsychological assessment, we explored (1) source memory, using a reality-monitoring task, (2) episodic autobiographical memory, including both the recollection of the past memories and the ability to imagine future personal events, with an episodic future thinking task (EFT), (3) the sense of self, with questionnaires targeting self-representations, self-esteem and self-competence. Results: The results showed the expected source memory deficits and poor episodic future thinking, whereas episodic autobiographical memory was preserved, contrary to the episodic memory dysfunction usually evidenced in adult confabulators. The confabulations produced by this teenager displayed a clear positive bias, seemed to fit to personal/social goals and to wishful ideations, and were associated with an above average self-esteem and self-representation. Conclusions: These results support the hypothesis of self-identity and emotional regulatory roles of the confabulations. Although the literature on confabulating children/teenagers is nearly non-existent, a more systematic screening of confabulations should be conducted in order to avoid false interpretation to strange discourse or behavior.

Evidence of preserved audience design with aging in interactive conversation.

Speakers tailor referential expressions to the listener's knowledge, a phenomenon called audience design. Audience design requires access to partner-specific representations in memory, which could be compromised among older adults who experience memory declines. In fact, little is known about how the memory representation of shared knowledge with a conversational partner influences audience design in multiparty conversation. We examined how young and older adults tailor their utterances for partners holding different representations of the same item. Both younger and older adults successfully adjusted their referential expressions to the current partner's knowledge state in a live conversation. However, when memory was explicitly probed, older adults showed a source memory deficit in distinguishing which partner held which label. These results suggest that explicit memory may not be necessary for audience design, and that implicit memory processes, which are preserved with aging, may contribute to effective audience design. The findings highlight a pathway to preserved communicative competence with aging and the roles of multiple memory systems including both implicit and explicit systems. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The Impact of Focusing on Different Features During Encoding on Young and Older Adults’ Source Memory

AbstractAge-related source memory deficits result, in part, because young and older adults attend to different information. We asked whether focusing young and older adults‘ attention on specific features at encoding would result in similar subjective experiences of the vividness of the features and how this might affect source memory. Ratings of the vividness of visual detail, emotion, and associations were similar for young and older adults both when they were perceiving pictures and when they were thinking about them after a brief delay. Although young adults had better source memory than older adults, source accuracy did not differ depending on feature attended, and correlations between ratings and source memory showed that focus on the different types of information was equally predictive of source memory accuracy for young and older adults. Although preliminary, the results suggest that when attention is focused on specific information at encoding, young and older adults later use the various categories of source-specifying information similarly in making source attributions. Nevertheless, older adults did worse on the source test, suggesting they had less discriminable source information overall, this information was not well bound, and/or they experienced difficulty in strategic retrieval and monitoring processes.

Source Memory in Korsakoff Syndrome: Disentangling the Mechanisms of Temporal Confusion.

Korsakoff syndrome (KS), most frequently resulting from alcohol dependence (ALC), is characterized by severe anterograde amnesia. It has been suggested that these deficits may extend to other memory components, and notably source memory deficits involved in the disorientation and temporal confusion frequently observed in KS. However, the extent of this source memory impairment in KS and its usefulness for the differential diagnosis between ALC and KS remain unexplored. Nineteen patients with KS were compared with 19 alcohol-dependent individuals and 19 controls in a source memory test exploring temporal context confusions ("continuous recognition task"). Episodic memory and psychopathological comorbidities were controlled for. While no source memory deficit was observed in ALC, KS was associated with a significant presence of temporal context confusion, even when the influence of comorbidities was taken into account. This source memory impairment did not appear to be related to performances on episodic memory or executive functions. Patients with KS displayed source memory deficits, as indexed by temporal context confusions. The absence of a relationship with episodic memory performances seems to indicate that source memory impairment is not a mere by-product of amnesia. As ALC was associated with preserved source memory, the presence of temporal context confusion may serve as a complementary tool for the differential diagnosis between ALC and KS.

FMRI activity during associative encoding is correlated with cardiorespiratory fitness and source memory performance in older adults

Older adults (OA), relative to young adults (YA), exhibit age-related alterations in functional Magnetic Resonance Imaging (fMRI) activity during associative encoding, which contributes to deficits in source memory. Yet, there are remarkable individual differences in brain health and memory performance among OA. Cardiorespiratory fitness (CRF) is one individual difference factor that may attenuate brain aging, and thereby contribute to enhanced source memory in OA. To examine this possibility, 26 OA and 31 YA completed a treadmill-based exercise test to evaluate CRF (peak VO2) and fMRI to examine brain activation during a face-name associative encoding task. Our results indicated that in OA, peak VO2 was positively associated with fMRI activity during associative encoding in multiple regions including bilateral prefrontal cortex, medial frontal cortex, bilateral thalamus and left hippocampus. Next, a conjunction analysis was conducted to assess whether CRF influenced age-related differences in fMRI activation. We classified OA as high or low CRF and compared their activation to YA. High fit OA (HFOA) showed fMRI activation more similar to YA than low fit OA (LFOA) (i.e., reduced age-related differences) in multiple regions including thalamus, posterior and prefrontal cortex. Conversely, in other regions, primarily in prefrontal cortex, HFOA, but not LFOA, demonstrated greater activation than YA (i.e., increased age-related differences). Further, fMRI activity in these brain regions was positively associated with source memory among OA, with a mediation model demonstrating that associative encoding activation in medial frontal cortex indirectly influenced the relationship between peak VO2 and subsequent source memory performance. These results indicate that CRF may contribute to neuroplasticity among OA, reducing age-related differences in some brain regions, consistent with the brain maintenance hypothesis, but accentuating age-differences in other regions, consistent with the brain compensation hypothesis.

Aging affects the interaction between attentional control and source memory: an fMRI study.

Age-related source memory impairments may be due, at least in part, to deficits in executive processes mediated by the PFC at both study and test. Behavioral work suggests that providing environmental support at encoding, such as directing attention toward item-source associations, may improve source memory and reduce age-related deficits in the recruitment of these executive processes. The present fMRI study investigated the effects of directed attention and aging on source memory encoding and retrieval. At study, participants were shown pictures of objects. They were either asked to attend to the objects and their color (source) or to their size. At test, participants determined if objects were seen before, and if so, whether they were the same color as previously. Behavioral results showed that direction of attention improved source memory for both groups; however, age-related deficits persisted. fMRI results revealed that, across groups, direction of attention facilitated medial temporal lobe-mediated contextual binding processes during study and attenuated right PFC postretrieval monitoring effects at test. However, persistent age-related source memory deficits may be related to increased recruitment of medial anterior PFC during encoding, indicative of self-referential processing, as well as underrecruitment of lateral anterior PFC-mediated relational processes. Taken together, this study suggests that, even when supported, older adults may fail to selectively encode goal-relevant contextual details supporting source memory performance.

La mémoire de la source

ObjectivesSource monitoring is characterized by the ability to recognize the origin of the information. Memory deficits of the source would be an important dimension in the understanding of the hallucinations in schizophrenia. The objective of the study is to compare the performance of the source memory of two resistant populations compared to healthy volunteers. Materials and methodsIncluded subjects were 20 schizophrenic patients with refractory hallucinations, 10 refractory depression and 20 healthy subjects were evaluated. All clinical subjects met criteria for resistant disease. Source memory deficits were measured using a computerized source memory task, consisting of two subtests “hear” and “say”. This task assesses the ability to recognize the source of information that can come from either the subject itself or from an external source. ResultsPerformances of the three groups were compared on the number of correct recognitions for each test and the number of errors, which are the following ones: inversions, false recognitions and omissions. The data appear to reflect cognitive deficits present in each psychiatric population compared with healthy volunteers. These deficits seem to be of different types depending on the population. Refractory hallucinating schizophrenic subjects attribute significantly more auto-generated information to an external source than subjects with refractory depression. Moreover, the errors produced by depressed subjects occur more in information processing capacity as encoding and memory storage deficits. ConclusionsSource memory deficits are present in both pathologies. They seem to play a different role depending on disorders presented and are suggested as a cognitive marker to consider.

Delusional Confusion of Dreaming and Reality in Narcolepsy

We investigated a generally unappreciated feature of the sleep disorder narcolepsy, in which patients mistake the memory of a dream for a real experience and form sustained delusions about significant events. We interviewed patients with narcolepsy and healthy controls to establish the prevalence of this complaint and identify its predictors. Academic medical centers in Boston, Massachusetts and Leiden, The Netherlands. Patients (n = 46) with a diagnosis of narcolepsy with cataplexy, and age-matched healthy healthy controls (n = 41). N/A. "Dream delusions" were surprisingly common in narcolepsy and were often striking in their severity. As opposed to fleeting hypnagogic and hypnopompic hallucinations of the sleep/wake transition, dream delusions were false memories induced by the experience of a vivid dream, which led to false beliefs that could persist for days or weeks. The delusional confusion of dreamed events with reality is a prominent feature of narcolepsy, and suggests the possibility of source memory deficits in this disorder that have not yet been fully characterized.

¿Quién hizo qué? Diferencias entre adultos jóvenes y mayores en la memoria para un atraco

Due to the increased life expectancy of the older population, there is a growing probability for an elderly person to testify as an eyewitness or a victim of a robbery or a similar crime. However, little is known about aging effects on testimony accuracy and about circumstances in which older adults would be more prone to memory errors than younger adults. In this study older and younger adults´ memory for actions of a robbery was examined with a recognition test. Although no differences were found in hits, the older adults had a higher proportion of false alarms and showed less accurate recognition than younger adults. In addition, the older adults were less able to attribute actions that occurred during the robbery to their correct sources. Thus, source-memory deficits may contribute to explain older adults’ less accurate recognition, a finding that should be taken into account in real-life eyewitness situations where an elderly person is involved.

Age-related differences in agenda-driven monitoring of format and task information

Age-related source memory deficits may arise, in part, from changes in the agenda-driven processes that control what features of events are relevant during remembering. Using fMRI, we compared young and older adults on tests assessing source memory for format (picture, word) or encoding task (self-, other-referential), as well as on old–new recognition. Behaviorally, relative to old–new recognition, older adults showed disproportionate and equivalent deficits on both source tests compared to young adults. At encoding, both age groups showed expected activation associated with format in posterior visual processing areas, and with task in medial prefrontal cortex. At test, the groups showed similar selective, agenda-related activity in these representational areas. There were, however, marked age differences in the activity of control regions in lateral and medial prefrontal cortex and lateral parietal cortex. Results of correlation analyses were consistent with the idea that young adults had greater trial-by-trial agenda-driven modulation of activity (i.e., greater selectivity) than did older adults in representational regions. Thus, under selective remembering conditions where older adults showed clear differential regional activity in representational areas depending on type of test, they also showed evidence of disrupted frontal and parietal function and reduced item-by-item modulation of test-appropriate features. This pattern of results is consistent with an age-related deficit in the engagement of selective reflective attention.

The influence of directed attention at encoding on source memory retrieval in the young and old: An ERP study

Neuroimaging evidence suggests that older adults exhibit deficits in frontally-mediated strategic retrieval processes, such as post-retrieval monitoring. Behavioral research suggests that explicitly directing attention toward source features during encoding may improve source memory for both young and older adults and alleviate age-related source memory impairments, in part, by reducing demands on post-retrieval monitoring. We investigated this hypothesis in the present event-related potential (ERP) study. Young and older adults attended to either objects and their presented color (source) or to the object alone during study and made color source memory decisions at test. We attempted to match performance between groups by halving the memory load for older adults. Behavioral results showed that, while direction of attention to object and color improved source memory for both groups, older adults benefited less than the young. ERPs revealed that demands on late right frontal effects, indicative of post-retrieval monitoring, were similarly reduced by directed attention at encoding for both groups. However, older adults showed reduced ERP correlates of recollection (parietal old–new effect), as well as a sustained widespread negativity, potentially indicative of memory searches for perceptual details in the face of impaired recollection. These results suggest that older adults, like the young, can engage in post-retrieval monitoring when source details are difficult to recover. However, impaired recollection may underlie persistent age-related source memory deficits, even when encoding is supported via directed attention.

Memory binding in clinical and non-clinical psychotic experiences: How does the continuum model fare?

Introduction. Both clinical and non-clinical auditory hallucinations (AH) have been associated with source memory deficits, supporting a continuum of underlying cognitive mechanisms, though few studies have employed the same task in patient and nonpatient samples. Recent commentators have called for more debate on the continuum model of psychosis. Consequently, the current study investigated the continuity model of AH with reference to memory binding. Methods. We used an identical voice and word recognition memory task to assess binding in two separate studies of: (1) healthy hallucination-prone individuals and controls (30 high and 30 low scorers on the Launay-Slade Hallucination Scale–Revised) and (2) schizophrenia patient samples (32 with AH, 32 without AH) and 32 healthy controls. Results. There was no evidence of impaired binding in high hallucination-prone, compared to low hallucination-prone individuals. In contrast, individuals with schizophrenia (both with and without AH) had difficulties binding (remembering “who said what”), alongside difficulties remembering individual words and voices. Binding ability and memory for voices were also negatively linked to the loudness of hallucinated voices reported by patients with AH. Conclusions. These findings suggest that different mechanisms may exist in clinical and non-clinical hallucinators, adding to the growing debate on the continuum model of psychotic symptoms.

Age-Related Source Memory Deficits Persist Despite Superior Item Memory

Source and item memory for faces of former United States Presidents were assessed in nondemented older adults over 65 years of age (n = 20) and young adults 18 to 25 years of age (n = 20). During the study phase, a male and a female source each presented pictures of faces to the participant one at a time. To assess source memory, the participant was asked to indicate whether a face from the study phase was presented by the male or female. To assess item memory, a study phase face and distractor face were presented and the participant was asked to indicate which was presented previously. Older adults displayed significantly better item memory for the faces of presidents compared to young adults. However, despite showing superior item memory, source memory still was impaired in older adults compared to young adults. The ability of older adults to efficiently integrate source and item information may be compromised to such a large extent that enhanced item memory does not appear to minimize or negate age-related source memory deficits. The findings demonstrate the robust effects of aging on source memory.

The effects of aging on material-independent and material-dependent neural correlates of contextual binding

Previous behavioral research suggests that older adults exhibit impairments in source memory across a multitude of stimuli and associated details, possibly due to a deficit in contextual binding. However, it is unclear whether this binding deficit results from alterations in processes that are material-independent, processes that are specific to particular materials, or some combination of the two. We used event-related fMRI to investigate the effect of aging on contextual binding and associated neural activity for words and objects. Behavioral data showed similar age-related deficits in source memory accuracy for both words and objects. Imaging results revealed that young and older adults recruited similar networks of regions in support of contextual binding, independent of material, including the lateral prefrontal cortex (PFC) and hippocampus. Material-dependent binding effects were also present for both groups in ventrolateral prefrontal and parahippocampal cortices for words and objects, respectively. Older adults showed smaller material-independent contextual binding effects in frontal regions, namely the left dorsolateral PFC, and larger binding effects in the hippocampus. Further, age-related declines in object processing effects in extrastriate regions correlated with poorer source accuracy for objects. Collectively, these results suggest that age-related source memory deficits may be primarily due to changes in material-independent contextual binding processes. However, these impairments may be further impacted by impoverished item representations in material-specific processing regions.

On Identifying the Processes Underlying Schizophrenic Speech Disorder

Speech of people with schizophrenia is often difficult to follow. There is evidence that neuropsychological deficits associated with schizophrenia explain some of the variance in speech disorder, but its nature and causes overall are not well understood. This study rated speech samples from 60 schizophrenic outpatients for thought disorder, conceptual disorganization, linguistic structural breakdown, and communication failure. A battery of neuropsychological tests potentially relevant to coherent speech production was administered, and associations between these variables and the speech measures were assessed. Consistent with previous research, the measure of functional effect, communication failure, was more highly associated with neuropsychological test performance than were the measures of putative cause: thought disorder, conceptual disorganization, or linguistic structural breakdown. Performance on tests of attention, immediate memory, working memory, organizational sequencing, and conceptual sequencing all were significantly related to the frequency of communication failures in the speech. In hierarchical regression, attention, working memory, and conceptual sequencing each contributed significantly and together explained 29% of the variance. Some other potential contributors to test in future research include auditory attention, internal source memory, emotional disturbances, and social cognitive deficits.

False Recognition and Source Attribution for Actions of an Emotional Event in Older and Younger Adults

In two experiments recognition of actions of a robbery presented in a video was examined in older and younger adults. In both experiments older adults had more false alarms and showed less accurate recognition than younger adults. In addition, when participants were asked in Experiment 1 to indicate Remember/Know/Guess judgments for actions they considered true, older adults accepted more false actions with Remember judgments. And when participants were asked in Experiment 2 to attribute the source (i.e., perpetrator), the older adults were less able to attribute actions that occurred during the robbery to their correct sources. Furthermore, we found a robust positive correlation between source attribution ability and recognition accuracy. Thus, source-memory deficits may contribute to older adults' false memories in real-life eyewitness situations.

The role of recollection in source memory: An examination of schizophrenia patients and their first-degree relatives

Source recognition memory deficits have repeatedly been observed in people with schizophrenia (SZ), and have also recently been observed in their first-degree relatives. These deficits have been hypothesized to result, at least in part, from impairments in the conscious recollection process. Although other processes are clearly also affected in SZ, it has been proposed that impairments in the conscious recollection process could be a parsimonious explanation for the source memory deficits observed in their relatives.Here, we tested 25 patients with SZ and 34 of their non-affected parents, as well as two groups of matched healthy controls, on a short-term associative memory task that shares the characteristics of standard source recognition tasks but minimizes the need for recollection of stored information from memory. This task was administered in order to determine if deficits can still be observed in these people when involvement of the conscious recollection process is minimized.We observed deficits on our short-term source memory task in people with SZ, but their first-degree relatives did not share this deficit. These results support the idea that multiple memory processes supporting associative/source memory are affected in SZ, whereas the source memory deficits previously observed in relatives of SZ seem specific to tasks that rely on the conscious recollection process.