A snapshot of autobiographical memory retrieval characteristics

This study attempts to replicate and extend the results of Burt (1992a), using more ecologically valid memory cues. Twenty-seven undergraduate students used 138 rolls of film over the 1992-3 summer vacation. The film produced approximately 4900 autobiographical photographs, which were categorized as to the nature of the cues (event information) they contained (e. g. activity, location, participant). A sample of the subject's autobiographical photographs, and a set of other individuals autobiographical photographs (autobiographical foils), were presented to each subject via a tachistoscope. The subjects were asked to indicate when they had retrieved the 'circumstances and associated context' surrounding the scene depicted in each photograph or had decided the latter was not possible. Differences in memory retrieval times were found between the foils and autobiographical photographs and across the cue categories. The results suggest that autobiographical event memory structures are formed around the most unique event attribute. Rehearsal of an event and occurrence of an experience within an extended event (e. g. a holiday) were also found to predict memory retrieval time.     

Effect of self-discrepancy on specificity of autobiographical memory retrieval

Research using a cue word paradigm has consistently shown that depression, in both adults and adolescents, is associated with difficulties in retrieving specific autobiographical memories. Inspired by previous work stating that depressed feelings are related to a perceived discrepancy between attributes of the actual and the ideal self, the present study aimed to investigate the hypothesis that cues bringing discrepancies between the actual and ideal selves to the foreground might promote or facilitate the recall of overgeneral (instead of specific) autobiographical memories. In two studies adolescents provided autobiographical memories in response to 10 high-discrepant and 10 low-discrepant words. As predicted, results in both studies showed an effect of cue word discrepancy on the specificity of autobiographical memories such that participants retrieved a smaller proportion of specific and a greater proportion of overgeneral memories in response to high-discrepant words as compared to low-discrepant words. The findings are discussed in terms of the self-memory system (SMS) as a conceptual framework of autobiographical memory (Conway & Pleydell-Pearce, 2000).     

Non-ruminative processing reduces overgeneral autobiographical memory retrieval in students

It has been suggested that overgeneral memory (OGM) represents a vulnerability marker for depression [Williams, J. M. G., Barnhofer, T., Crane, C., Hermans, D., Raes, F., Watkins, E., et al. (2007). Autobiographical memory specificity and emotional disorder. Psychological Bulletin, 133, 122-148]. One important underlying mechanism involved is rumination [e.g., Watkins, E., & Teasdale, J. D. (2001). Rumination and overgeneral memory in depression: Effects of self-focus and analytic thinking. Journal of Abnormal Psychology, 110, 353-357; Watkins, E., & Teasdale, J. D. (2004). Adaptive and maladaptive self-focus in depression. Journal of Affective Disorders, 82, 1-8]. It is as yet unclear to what extent the relationship between rumination and OGM also applies to nonclinical groups. The present study investigated this relationship in a nonclinical student sample, using an innovative sentence completion procedure to assess OGM. As hypothesized, the experimental induction of a concrete, process-focused (or non-ruminative) thinking style (n=102) led to less OGMs as compared to the experimental induction of an abstract, evaluative (or ruminative) thinking style (n=93). The present results add to the accumulating body of evidence that abstract, evaluative (or ruminative) thinking is a crucial underlying process of OGM, and expand prior literature by extending this idea to nonclinical individuals and by using a new procedure to assess OGM.     

Mechanisms of autobiographical memory retrieval in younger and older adults

In this study, retrieval of autobiographical memories was compared within or without the context of a lifetime period and between younger and older adults. The results of two experiments demonstrated that memories were more accessible for younger and older adults when they were retrieved within a time period context than without such context. However, when the retrieval context was more constrained and limited to cue word memories, the benefit of retrieval context disappeared. The results also suggested that as compared with younger adults, older adults were more likely to selectively retain memories with distinctive characteristics, such as being self-relevant and emotionally intense, particularly when remote memories were involved. Mechanisms of autobiographical memory retrieval in younger and older adults.     

Aging and autobiographical memory: dissociating episodic from semantic retrieval

Cognitive aging research documents reduced access to contextually specific episodic details inolder adults, whereas access to semantic or other nonepisodic information is preserved or facilitated. The present study extended this finding to autobiographical memory by using a new measure; the Autobiographical Interview. Younger and older adults recalled events from 5 life periods. Protocols were scored according to a reliable system for categorizing episodic and nonepisodic information. Whereas younger adults were biased toward episodic details reflecting happenings, locations, perceptions, and thoughts, older adults favored semantic details not connected to a particular time and place. This pattern persisted after additional structured probing for contextual details. The Autobiographical Interview is a useful instrument for quantifying episodic and semantic contributions to personal remote memory.     

Neural networks supporting autobiographical memory retrieval in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) affects the functional recruitment and connectivity between neural regions during autobiographical memory (AM) retrieval that overlap with default and control networks. Whether such univariate changes relate to potential differences in the contributions of the large-scale neural networks supporting cognition in PTSD is unknown. In the present functional MRI study, we employed independent-component analysis to examine the influence of the engagement of neural networks during the recall of personal memories in a PTSD group (15 participants) as compared to non-trauma-exposed healthy controls (14 participants). We found that the PTSD group recruited similar neural networks when compared to the controls during AM recall, including default-network subsystems and control networks, but group differences emerged in the spatial and temporal characteristics of these networks. First, we found spatial differences in the contributions of the anterior and posterior midline across the networks, and of the amygdala in particular, for the medial temporal subsystem of the default network. Second, we found temporal differences within the medial prefrontal subsystem of the default network, with less temporal coupling of this network during AM retrieval in PTSD relative to controls. These findings suggest that the spatial and temporal characteristics of the default and control networks potentially differ in a PTSD group versus healthy controls and contribute to altered recall of personal memory.     

The influence of cognitive and emotional suppression on overgeneral autobiographical memory retrieval

Over-general autobiographical memory (OAM) retrieval is characterized by retrieval of categoric autobiographical memories. According to the CarFAX model, this tendency may result from avoidance which functions to protect the person against recalling details of upsetting memories. This study tested whether avoidance strategies impact on the ability to retrieve specific autobiographical memories. Healthy participants (N = 51) watched a negative video clip and were instructed to either suppress any thought (thought suppression), suppress any feeling (emotional inhibition), or think and feel naturally (controls) in response to the video. Participants then completed the Autobiographical Memory Test. Participants engaging in either thought suppression or emotional inhibition retrieved fewer categoric autobiographical memories than controls. These findings challenge the affect regulation component of the CarFAX model insofar as they suggest that regulatory strategies that aim to reduce awareness of adverse emotional memories do not necessarily lead to increased recall of categoric autobiographical memories.     

Increased regional cerebral glucose metabolism and semantic memory performance in Alzheimer's disease: A pilot double blind transdermal nicotine positron emission tomography study

Nicotinic receptor dysfunction and impaired semantic memory occur early in Alzheimer's disease patients (AD). Previous research implied that nicotine's ability to enhance alertness, arousal, and cognition in a number of nonclinical populations was a function of its ability to stimulate CNS nicotinic cholinergic receptors. In this study it was hypothesized that transdermal administration of nicotine would increase both regional cerebral glucose metabolism (rCMRglc) and semantic memory (as assessed by verbal fluency). Two mild AD and two elderly controls underwent positron emission tomography scanning during a double blind nicotinic agonist verbal fluency challenge procedure. rCMRglc increases occurred in both AD patients, but not controls. In the two AD patients, verbal fluency scores increased by an average of 17%. One elderly control's verbal fluency increased, and the other decreased. These findings suggest that nicotine's effect on metabolism and verbal fluency is due to its ability to stimulate the cholinergic system.     

Toward neuroanatomical models of analogy: a positron emission tomography study of analogical mapping

Several brain regions associated with analogical mapping were identified using (15)O-positron emission tomography with 12 normal, high intelligence adults. Each trial presented during scanning consisted of a source picture of colored geometric shapes, a brief delay, and a target picture of colored geometric shapes. Analogous pictures did not share similar geometric shapes but did share the same system of abstract visuospatial relations. Participants judged whether each source-target pairing was analogous (analogy condition) or identical (literal condition). The results of the analogy-literal comparison showed activation in the dorsomedial frontal cortex and in the left hemisphere; the inferior, middle, and medial frontal cortices; the parietal cortex; and the superior occipital cortex. Based on these results as well as evidence from relevant cognitive neuroscience studies of reasoning and of executive working memory, we hypothesize that analogical mapping is mediated by the left prefrontal and inferior parietal cortices.     

Unusual visual symptoms and Ganser-like state due to cerebral injury: a case study using (18)F-deoxyglucose positron emission tomography

Bizarre visual symptoms and absurd verbal responses to questions, in a 32-year-old man recovering from a severe asthma episode, suggested a possible conversion disorder with Ganser-like symptoms. Positron Emission Tomography (PET)revealed bilateral lesions involving occipital association cortex and posterior temporal and parietal lobes, most likely infarcts from hypoxia. PET permitted correlation of the patient's specific cortical lesions with his unusual perceptual, cognitive, and speech symptoms, including Ganser-like state, to a degree not previously possible in such cases.     

The role of working memory capacity in autobiographical retrieval: individual differences in strategic search

Remembering previous experiences from one's personal past is a principal component of psychological well-being, personality, sense of self, decision making, and planning for the future. In the current study the ability to search for autobiographical information in memory was examined by having college students recall their Facebook friends. Individual differences in working memory capacity manifested itself in the search of autobiographical memory by way of the total number of friends remembered, the number of clusters of friends, size of clusters, and the speed with which participants could output their friends' names. Although working memory capacity was related to the ability to search autobiographical memory, participants did not differ in the manner in which they approached the search and used contextual cues to help query their memories. These results corroborate recent theorising, which suggests that working memory is a necessary component of self-generating contextual cues to strategically search memory for autobiographical information.     

A developmental psychopathology model of overgeneral autobiographical memory

Overgeneral memory (OGM) is a phenomenon that refers to difficulty retrieving specific autobiographical memories. The tendency to be overgeneral in autobiographical memory recall has been commonly observed among individuals with emotional disorders compared to those without emotional disorders. Despite significant advances in identifying mechanisms that underlie OGM, etiological models are not particularly developmental in nature and, instead, are focused on identifying isolated cognitive presentations of individuals with high OGM. The aim of the current paper is to utilize a developmental psychopathology framework, which emphasizes the interface between typical and atypical development, and risk and protective factors at multiple ecological levels, to propose a comprehensive model of OGM development. Specifically, (1) the progression of current etiological models of OGM is reviewed; (2) developmental theory and research on autobiographical memory that have relevance for OGM are discussed; and (3) an integrative model of OGM that includes processes at psychological, biological, social, and cultural levels is proposed. Directions for future research are formulated and treatment implications derived from this perspective are addressed.     

A cognitive assessment of highly superior autobiographical memory

Highly Superior Autobiographical Memory (HSAM) is characterised as the ability to accurately recall an exceptional number of experiences and their associated dates from events occurring throughout much of one's lifetime. The source of this ability has only begun to be explored. The present study explores whether other enhanced cognitive processes may be critical influences underlying HSAM abilities. We investigated whether enhanced abilities in the domains of verbal fluency, attention/inhibition, executive functioning, mnemonic discrimination, perception, visual working memory, or the processing of and memory for emotional details might contribute critically to HSAM. The results suggest that superior cognitive functioning is an unlikely basis of HSAM, as only modest advantages were found in only a few tests. In addition, we examined HSAM subjects’ memory of the testing episodes. Interestingly, HSAM participants recalled details of their own experiences far better than those experiences that the experimenter shared with them. These findings provide additional evidence that HSAM involves, relatively selectively, recollection of personal, autobiographical material.     

A positron emission tomography study of short- and long-term treatment effects on functional brain activation in adults who stutter

Previous studies have shown that fluency-inducing techniques, such as choral speech, result in changes in neural activation as measured by functional neuroimaging. In the present study, positron emission tomography was used to investigate the effects of intensive behavioural treatment, followed by a 1-year maintenance program, on the pattern of cortical and subcortical activation in stuttering adults during silent and oral reading of single words. The results indicate changes in activation lateralisation, as well as a general reduction in overactivation, especially in the motor cortex, following treatment. The results are discussed in light of previous functional imaging studies with stuttering adults.

Educational objectives: The reader will learn about and be able to describe the: (1) use of functional neuroimaging PET in the study of stuttering; (2) differences in neural activation between stuttering and non-stuttering adults; and (3) effects of behavioural fluency treatment on cortical and subcortical activations in stuttering speakers.     

Olfactory cuing of autobiographical memory

In Experiment 1, subjects were presented with either the odors or the names of 15 common objects. In Experiment 2, subjects were presented with either the odors, photographs, or names of 16 common objects. All subjects were asked to describe an autobiographical memory evoked by each cue, to date each memory, and to rate each memory on vividness, pleasantness, and the number of times that the memory had been thought of and talked about prior to the experiment. Compared with memories evoked by photographs or names, memories evoked by odors were reported to be thought of and talked about less often prior to the experiment and were more likely to be reported as never having been thought of or talked about prior to the experiment. No other effects were consistently found, though there was a suggestion that odors might evoke more pleasant and emotional memories than other types of cues. The relation of these results to the folklore concerning olfactory cuing is discussed.     

The neural correlates of driving performance identified using positron emission tomography

Driving is a complex behavior involving multiple cognitive domains. To identify neural correlates of driving performance, [15O]H2O positron emission tomography was performed using a simulated driving task. Compared with the resting condition, simulated driving increased regional cerebral blood flow (rCBF) in the cerebellum, occipital, and parietal cortices. Correlations between rCBF and measurements of driving performance were evaluated during simulated driving. Interestingly, rCBF in the thalamus, midbrain, and cerebellum were positively correlated with time required to complete the course and rCBF in the posterior cingulate gyrus was positively correlated with number of crashes during the task. These brain regions may thus play roles in the maintenance of driving performance.     

The retrieval of sentences from memory: A speed-accuracy study

A speed-accuracy tradeoff method was used to study the retrieval dynamics for recognition memory of parts of sentences. All sentences contained a subject, verb, object, location, and time. Recognition accuracy increased from chance at a processing time of about 0.5 sec to asymptotic accuracy at about 3 sec. The asymptotic accuracy levels for subject-verb, subject-object or verb-object recognition probes exceeded those of pair probes containing times or locations. This result suggests that the former may be more closely associated in semantic memory. The only difference among speed-accuracy curves was in asymptotic accuracy. The chance intercept and the rate of increase in accuracy were similar for all pair probes. A second finding was that the speed-accuracy curves for triple probes (e.g., subject-verb-object) were virtually identical to those of the comparable pair probes. These results appear to contradict a serial search hypothesis for the access of information from semantic memory. They support a parallel, direct-access hypothesis.     

Body posture facilitates retrieval of autobiographical memories

We assessed potential facilitation of congruent body posture on access to and retention of autobiographical memories in younger and older adults. Response times were shorter when body positions during prompted retrieval of autobiographical events were similar to the body positions in the original events than when body position was incongruent. Free recall of the autobiographical events two weeks later was also better for congruent-posture than for incongruent-posture memories. The findings were similar for younger and older adults, except for the finding that free recall was more accurate in younger adults than in older adults in the congruent condition. We discuss these findings in the context of theories of embodied cognition.     

Emotional organization of autobiographical memory

The emotional organization of autobiographical memory was examined by determining whether emotional cues would influence autobiographical retrieval in younger and older adults. Unfamiliar musical cues that represented orthogonal combinations of positive and negative valence and high and low arousal were used. Whereas cue valence influenced the valence of the retrieved memories, cue arousal did not affect arousal ratings. However, high-arousal cues were associated with reduced response latencies. A significant bias to report positive memories was observed, especially for the older adults, but neither the distribution of memories across the life span nor response latencies varied across memories differing in valence or arousal. These data indicate that emotional information can serve as effective cues for autobiographical memories and that autobiographical memories are organized in terms of emotional valence but not emotional arousal. Thus, current theories of autobiographical memory must be expanded to include emotional valence as a primary dimension of organization.