Memory of myself: Autobiographical memory and identity in Alzheimer's disease

A number of theories posit a relationship between autobiographical memory and identity. To test this we assessed the status of autobiographical memory and identity in 20 individuals with Alzheimer's disease (AD) and 20 age‐matched controls, and investigated whether degree of autobiographical memory impairment was associated with changes in identity. Two tests of autobiographical memory (Autobiographical Memory Interview, autobiographical fluency) and two measures of identity (Twenty Statements Test, identity items of the Tennessee Self Concept Scale) were administered. AD participants exhibited significant impairments on both memory tests, and changes in the strength, quality, and direction of identity relative to controls. Impairments of some components of autobiographical memory, particularly autobiographical memory for childhood and early adulthood, were related to changes in the strength and quality of identity. These findings support the critical role of early adulthood autobiographical memories (16–25 years) in identity, and suggest autobiographical memory loss affects identity.     

'I remember therefore I am, and I am therefore I remember': exploring the contributions of episodic and semantic self-knowledge to strength of identity

The present research explores the relationship between the two components of autobiographical memory--episodic and semantic self-knowledge--and identity strength in older adults living in the community and residential care. Participants (N= 32) completed the autobiographical memory interview and measures of personal identity strength and multiple group memberships. Contrary to previous research, autobiographical memory for all time periods (childhood, early adulthood, and recent life) in the semantic domain was associated with greater strength in personal identity. Further, we obtained support for the hypothesis that the relationship between episodic self-knowledge and identity strength would be mediated by knowledge of personal semantic facts. However, there was also support for a reverse mediation model indicating that a strong sense of identity is associated with semantic self-knowledge and through this may enhance self-relevant recollection. The discussion elaborates on these findings and we propose a self-knowledge and identity model (SKIM) whereby semantic self-knowledge mediates a bidirectional relationship between episodic self-knowledge and identity.     

Memories defining the self in Alzheimer’s disease

ABSTRACT

There is a debate over the extent to which personal identity or the self is preserved in patients with Alzheimer’s disease (AD). Autobiographical memory deficits at early stages of AD could contribute to altering patients’ self. However, the nature of the relationship between autobiographical memory deficits and the self in AD has not been much investigated experimentally. In the present study, we aimed to investigate the integrative meaning of self-defining memories (SDMs) in early stages of AD and to analyse its relationship with the self-concept. The results showed that, when compared to the control group, AD patients less frequently extracted meaning from their SDMs and the meaning was less frequently tied to the self. Patients exhibited some altered aspects of the self-concept (i.e., complexity and strength), though some other components still persisted (i.e., valence and certainty). Correlation analyses showed that the impaired integrative meaning in the AD group was correlated with some changes in self-concept. We suggest that integrative meaning may act as a bridge between autobiographical memories and the self-concept, with reduced integration abilities appearing as a potential mechanism for the deterioration of the self-concept in AD.     

Effectiveness of follow‐up reminiscence therapy on autobiographical memory in pathological ageing

The objective is to examine the effects of reminiscence therapy (RT) on total, episodic and semantic autobiographical memory in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) groups, testing the effects of RT on different stages of autobiographical memory, and its effectiveness at follow‐up. A sample composed of 43 aMCI (27 treatments, 16 controls) and 30 AD (15 treatments, 15 controls) subjects were evaluated with the Autobiographical Memory Interview (AMI) test. The RT consisted of 10 sessions lasting 60 minutes each. Both groups, aMCI and AD, showed significant effects on overall autobiographical memory; aMCI showed significant main effects on episodic and semantic autobiographical memory in the treatment group, increasing scores in both cases. For AD, significant effects were observed on autobiographical episodic memory, showing an increase in the treatment group from Time 1 to follow‐up; semantic memory showed a decrease in the control group from Time 1 to follow‐up. Results show that RT implementation and follow‐up are effective in increasing autobiographical memory in subjects with aMCI and AD.     

The relation between verbal and visuospatial memory and autobiographical memory

The basic-systems approach (Rubin, 2005, 2006) states that autobiographical memory is supported by other cognitive systems and argues that autobiographical memories are constructed from interactions between cognitive systems, such as language, vision and emotion. Although deficiencies in one or more of the basic systems influence the properties of autobiographical memories, little is known about how these cognitive abilities and autobiographical memory are related. To assert whether participants with stronger cognitive abilities also perform better on autobiographical memory tests, participants who completed verbal and visuospatial memory tests also recorded one personal event, which they recalled after a certain interval. Participants who performed well on the verbal memory tests also had better retention for the personal event, providing support for the basic-systems approach to autobiographical memory and preliminary support for the view that people have more memories from adolescence and early adulthood because the memory system works optimally in these lifetime periods.     

Autobiographical memory deficits in schizophrenia

This study investigated autobiographical memory processes in a group of individuals diagnosed with schizophrenia and matched controls. The schizophrenia group displayed an overgeneral style of autobiographical memory retrieval on two widely used measures, and displayed problems retrieving both autobiographical facts and events. They showed a specific impairment in the recall of autobiographical events and facts in early adulthood, around the time of onset of their illness. Retrieval deficits were independent of mood state and premorbid intellectual functioning. The magnitude of the deficits in autobiographical memory retrieval specificity were considerably greater than any general impairments in episodic and working memory.     

Benchmark Memories in Adulthood: Central Domains and Predictors of Their Frequency

This study extended earlier research on the reminiscence bump phenomenon in autobiographical memory by examining the central domains and predictors of benchmark memories from a life history timeline and from three selected significant events. Memories elicited by these methods demonstrated the reminiscence bump as occurring in early adulthood. The central domains representing this era involved events with family and relationships followed by those related to education and work. Individual differences in socio-emotional variables associated with self and identity formations (i.e., family climate, defensive style, self-complexity, and adult attachment) were associated with the reminiscence bump. These findings support the self-narrative hypothesis that the reminiscence phenomenon is related to the process of identity formation in late adolescence and early adulthood.     

Discrepancy between subjective autobiographical reliving and objective recall: The past as seen by Alzheimer’s disease patients

This paper investigated whether Alzheimer’s disease (AD) patients may demonstrate a discrepancy between subjective autobiographical reliving and objective recall. To this end, 31 AD patients and 35 controls were asked to retrieve three autobiographical memories. For each memory, participants were asked to rate its subjective characteristics (e.g., reliving, travel in time, visual imagery…). Besides this subjective assessment, we analyzed recall objectively with regard to specificity. Results showed poorer subjective autobiographical reliving and objective recall in AD patients than in controls. A discrepancy (i.e., higher level of subjective reliving than of objective recall) was observed in AD but not in control participants. Despite a compromise in their objective recall, AD patients seemed to attribute a high value to their subjective autobiographical experience. This discrepancy can be attributed to a potential genuine consciousness experience in which mild AD patients can, to some extent, experience some subjective features of the past.     

Correlates of autobiographical memory specificity: the role of depression, anxiety and childhood trauma

The present study examined the role of childhood trauma, major depressive disorder (MDD), and anxiety disorder (AD) in overgeneral autobiographical memory. Ninety-three outpatients and 24 healthy controls completed a childhood trauma questionnaire and an autobiographical memory test (AMT). Results showed that MDD diagnosis rather than trauma history predicted AMT-performance. Memory specificity was not related to AD diagnosis, recovered MDD, or self-rated depression severity. The present findings cast doubts on theories that emphasize the role of childhood trauma in overgeneral autobiographical memory.     

Autobiographical memory functions and posttraumatic stress symptoms across adulthood

Previous research has documented robust individual differences in the functions served by autobiographical memories, and shown that different autobiographical memory functions are related to both positive and negative indicators of psychological well-being, and that their frequency varies with age. In this study, we examined the unique relationship between autobiographical memory functions and posttraumatic stress symptoms (PTSS) and whether such relationships varied with age across adulthood. A representative sample of 1040 adult Danes (20–70 years old) reported the frequency with which they recall autobiographical memories for different purposes as well as their level of posttraumatic stress disorder (PTSD) symptoms. Higher reflective and ruminative functions, as well as lower social function, predicted higher levels of PTSS. There were no moderating effects of age. The results suggest that although the frequency of various autobiographical functions varies throughout the adult years, their association with PTSS is similar across adulthood.     

Subliminal priming of autobiographical memories

The current research examined subliminal priming of autobiographical memories. In Experiment 1 the subliminal primes consisted of affect-associated words (positive vs negative) and were presented just before the participants retrieved specific experiences to cue-words. The subliminal primes produced an inhibitory effect on autobiographical memory retrieval, with significantly lower positive ratings given to the emotional content of experiences retrieved after positive primes than given to experiences retrieved after negative primes. The subliminal primes for the second experiment consisted of words that related to specific lifetime periods (early childhood vs late childhood/early adulthood). A negative priming effect resulted again, with earlier life experiences retrieved after the presentation of late childhood/early adulthood primes. We believe the negative priming effects obtained in both experiments are consistent with predictions based on the self-memory system model of autobiographical memory. The results of this research may also explain mood-incongruent recall.     

I'll keep you in mind: the intimacy function of autobiographical memory

An experimental study examined whether autobiographical memory serves the function of maintaining intimacy in romantic relationships. Young and older adults (N = 129) recalled either autobiographical relationship events or fictional relationship vignettes. Intimacy (warmth, closeness) was measured before and after remembering. Warmth was enhanced after recalling autobiographical events irrespective of individuals' age and gender; women also experienced gains in closeness. The role of memory characteristics (quality and content) in producing changes in intimacy was also examined. Personal significance of the autobiographical memory was the best predictor of warmth and closeness in the relationship, though how frequently the memory was thought or talked about, and how intimate the memory was also predicted levels of closeness, particularly for women. Results are discussed in terms of how autobiographical memories can be used to foster intimacy in romantic relationships across adulthood. Copyright © 2006 John Wiley & Sons, Ltd.     

Discrete changes in the frequency and functions of autobiographical reminiscence in Huntington's disease

ABSTRACT

Autobiographical memory is widely posited to serve self, social and directive functions. Recent evidence suggests marked autobiographical memory impairments in Huntington's disease (HD), however, no study to date has determined how the perceived functions of autobiographical reminiscence may be altered in HD. The current study aimed to assess the self-reported frequency and function of autobiographical reminiscence in HD. We assessed autobiographical reminiscence in late premanifest (n?=?16) and early stage HD (n?=?14), relative to healthy controls (n?=?30). Participants completed the Thinking About Life Experiences Scale Revised (TALE-R), which measures three putative functions of autobiographical memory (self, social, directive). People with manifest HD reported talking less frequently about the past compared to controls. In contrast, no group differences were found in terms of thinking about the past. Manifest HD participants further reported using their autobiographical memories for social functions less frequently compared to controls. No other group differences were evident in terms of self or directive functions of autobiographical memory. These self-report findings complement recent reports of autobiographical memory disruption on performance-based tasks in HD. Future studies exploring how changes in autobiographical reminiscence impact a sense of self continuity in HD will be important in this regard.     

Directed forgetting of autobiographical memory in mild Alzheimer's disease

Using the autobiographical directed forgetting method (Barnier et al., 2007), the present paper addressed the intentional inhibitory processes of episodic and semantic autobiographical memory in Alzheimer's disease (AD). Mild AD patients and healthy elderly people were instructed to either forget or to continue remembering previously generated autobiographical events. In a later recall test they were asked to reconstruct the early-generated memories regardless of the forget/remember instruction. Autobiographical reconstruction was further distributed into episodic and semantic memories. Results showed no forget instruction effect on episodic or semantic autobiographical recall with AD patients, whereas healthy elderly people were able to inhibit only episodic autobiographical memories. The findings suggest an impairment of the intentional inhibitory processes in autobiographical memory with AD and a relative preservation of these mechanisms with normal ageing. They also demonstrate an earlier decline in the intentional inhibitory processes compared to the autobiographical deterioration in AD.     

Directed forgetting of autobiographical memory in mild Alzheimer's disease

Using the autobiographical directed forgetting method (Barnier et al., 2007), the present paper addressed the intentional inhibitory processes of episodic and semantic autobiographical memory in Alzheimer's disease (AD). Mild AD patients and healthy elderly people were instructed to either forget or to continue remembering previously generated autobiographical events. In a later recall test they were asked to reconstruct the early-generated memories regardless of the forget/remember instruction. Autobiographical reconstruction was further distributed into episodic and semantic memories. Results showed no forget instruction effect on episodic or semantic autobiographical recall with AD patients, whereas healthy elderly people were able to inhibit only episodic autobiographical memories. The findings suggest an impairment of the intentional inhibitory processes in autobiographical memory with AD and a relative preservation of these mechanisms with normal ageing. They also demonstrate an earlier decline in the intentional inhibitory processes compared to the autobiographical deterioration in AD.     

Temporal references in dreams and autobiographical memory

In an attempt to determine whether temporal references identified in dreams follow the same temporal distributions as those documented for autobiographical memories, 28 younger women (18-35 years of age) and 30 older women (60-77 years of age) kept a home dream diary for 1 week and then slept 1 night in the laboratory for rapid eye movement sleep dream collection. The following morning, they identified temporal references in their dreams and produced a sample of autobiographical memories using the semantic cuing method. For both groups, there was a linear decrease in temporal references identified in dreams and autobiographical memories with increased remoteness for the last 30 years. As predicted, for the older group, there were similar cubic trends reflecting a disproportionately higher number of both temporal references identified in dreams and autobiographical memories from adolescence/early adulthood compared with adulthood and childhood. The results support the notion of continuity between waking and dreaming memory processes.     

Synaesthesia is linked to more vivid and detailed content of autobiographical memories and less fading of childhood memories

People with synaesthesia have enhanced memory on a wide range of laboratory tests of episodic memory, but very little is known about their real-world memory. This study used a standard measure of autobiographical remembering (the Autobiographical Memory Questionnaire, AMQ) considering four constructs (Recollection, Belief, Impact and Rehearsal) and two time periods (recent memories from adulthood, remote memories from childhood). Synaesthetes reported more Recollection (e.g., sensory detail) and Belief (e.g., confidence) which interacted with time, such that remote memories are reported to be comparatively better preserved in synaesthetes. This cannot be explained by synaesthetes recalling more salient episodes (the groups did not differ in Impact). It suggests instead that childhood memories have a special status in synaesthesia that reflects the different neurodevelopmental trajectory of this group. With regards to Rehearsal, controls tended to report that more recent memories tend to resurface (i.e., adulthood > childhood), but the synaesthetes showed the opposite dissociation (i.e., childhood > adulthood).     

Gender Identity Predicts Autobiographical Memory Phenomenology

Gender differences emerge regularly in autobiographical memory research. We suggest that gender differences in phenomenological self‐report measures of autobiographical memory are rooted in gender identity rather than categorical gender. Reminiscing about the past is perceived as a female‐typical activity, and therefore, gender‐typical individuals will conform to these stereotypes. In this study, 196 participants, age 18–40, each rated the phenomenology of four event memories. Ratings of feminine gender identity, also completed by participants, consistently correlated with MEQ scores, indicating that greater endorsement of feminine gender norms predicted higher memory quality and valence. Masculine gender identity also correlated with MEQ scores, but these correlations were less consistent. Findings suggest that a focus on gender identity can both explain the source of some gender differences in autobiographical memory and potentially explain some inconsistencies in the current literature.Copyright © 2016 John Wiley & Sons, Ltd.     

The reminiscence bump in the temporal distribution of the best football players of all time: Pelé, Cruijff or Maradona?

The reminiscence bump is the tendency to recall more autobiographical memories from adolescence and early adulthood than from adjacent lifetime periods. In this online study, the robustness of the reminiscence bump was examined by looking at participants' judgements about the quality of football players. Dutch participants (N = 619) were asked who they thought the five best players of all time were. The participants could select the names from a list or enter the names when their favourite players were not on the list. Johan Cruijff, Pelé, and Diego Maradona were the three most often mentioned players. Participants frequently named football players who reached the midpoint of their career when the participants were adolescents (mode = 17). The results indicate that the reminiscence bump can also be identified outside the autobiographical memory domain.     

Lexical and semantic fluency discrepancy scores in aMCI and early Alzheimer's disease

Episodic memory is compromised in amnestic mild cognitive impairment (aMCI), but lesser deficits in other cognitive domains are also commonly observed and may be helpful in identifying this group. The relative difference in performance on lexical and semantic fluency tasks may be a sensitive and specific measure in aMCI and early Alzheimer's disease (AD). We compared four groups of participants, 35 early AD, 47 aMCI, 24 healthy controls, and 18 depressive out‐patient controls, on semantic and lexical fluency as well as other neuropsychological tests. Early AD and aMCI patients showed a distinct pattern of semantic impairment in the two fluency measures compared with the healthy and depressive controls. The findings implicate early failure of the semantic memory system in aMCI and AD and suggest that consideration of the discrepancy in performance on semantic and lexical fluency measures may help in the early identification of AD.