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Alzheimer's disease (AD) is characterized by autobiographical memory deficits, with the ability to retrieve episodic-rich memories being particularly affected. Here, we investigated the influence of AD on a specific subtype of episodic memories known as flashbulb memories (i.e., the ability to remember the personal circumstances for the reception of important news events). We examined the frequency, characteristics, and the temporal distribution of flashbulb memories across the life span. To this aim, 28 older adults diagnosed with AD and a matched sample of 29 healthy older controls were probed for flashbulb memories for two historical events from each decade of their lives. They also estimated the subjective degree of reexperiencing for the memories reported. AD participants showed impaired access to flashbulb memories, the frequency of reported memories being lower than for healthy older adults. However, qualitative aspects of AD participants' flashbulb memories were quite similar to those of the controls, as no group differences were obtained with respect to the canonical categories or degree of reexperience. AD participants' flashbulb memories clustered during the early years of their life, consistent with a reminiscence bump, whereas healthy controls also reported memories dated to later lifetime periods. Our results suggest that probing for personal memories of important public events may serve as a powerful cue for detailed episodic memories in AD. [ABSTRACT FROM AUTHOR]

Autobiographical memory impairments are prominent in Alzheimer's disease (AD). Yet, life narratives of AD patients are scarcely examined. Here, twenty-one older adults diagnosed with probably AD and 22 age-matched healthy controls told their life story, and dated the events mentioned in these narratives. AD patients provided significantly fewer life story memories overall, but the proportion of memories with reference to specific events did not differ between groups. Patients included fewer negative events in their life story, while the emotional tone of narratives was similar across groups. Impairments were found on most structural aspects, with patients' narratives being less coherent and ending somewhere in the past, while no differences were seen for life story beginnings. Both groups showed a peak in remembered events dated to young adulthood, consistent with a reminiscence bump. However, in contrast to controls, patients displayed a steep drop in life story memories after the age of 30. For both groups, a high proportion of memories within the bump period were of life script events, consistent with the idea that the life script helps to structure the recall of personal life story memories, thus suggesting that AD patients still benefit from the retrieval support of this semantic structure. [ABSTRACT FROM AUTHOR]

Cultural life scripts are culturally transmitted semantic knowledge of the expected order and timing of major transitional events in a prototypical life course. This cognitive schema has been shown to serve as an important mnemonic template that guides retrieval from autobiographical memory, especially for positive and important life events. Autobiographical memory deficits are one of the earliest and most prominent symptoms in Alzheimer's disease (AD). However, no studies have examined cultural life scripts in patients with AD, despite semantic memory impairments being reported even in the early stages of the disease. The aim of the present work was to assess life-script knowledge in older adults diagnosed with AD, particularly in terms of knowledge for the content of life-script events and the timing and temporal order of these events. Twenty-one older adults diagnosed with AD and 22 healthy age-matched controls completed the standard life-script task (Berntsen & Rubin, 2004, Memory & Cognition, 32[3], 427–442). We found that while AD patients produced significantly fewer life-script events, the content of the generated events were quite consistent with those of the controls and the cultural norms. AD patients were particular impaired with regard to the normative timing and order of life-script events, suggesting that these components of the cultural life script are more vulnerable to cognitive decline. The findings are discussed in relation to impaired script knowledge and semantic memory deficits in AD. [ABSTRACT FROM AUTHOR]

Autobiographical memory is severely impaired in Alzheimer's disease (AD). However, previous research has focused primarily on voluntary memories—that is, memories retrieved deliberately following a request. Here we investigated the extent to which people with AD experience involuntary (spontaneous) autobiographical memories (IAMs), using a novel method to simulate involuntary retrieval in naturalistic settings. Twenty-one AD patients and 22 healthy controls viewed nostalgia films designed to elicit IAMs under two conditions: with or without prior reminiscence. AD patients expressed more IAMs and emotional reactions overall and showed higher physiological reactivity in response to the films than controls. Both groups verbalized more IAMs after having engaged in reminiscence prior to watching the film. The results provide novel evidence that AD patients frequently engage in involuntary remembering when viewing media content dated to their youth, suggesting that involuntary retrieval may act as an alternative route for accessing the personal past in AD. [ABSTRACT FROM AUTHOR]

Objective: Neuroimaging studies suggest that remembering the past and imagining the future engage a common brain network including several areas of the prefrontal cortex. Although patients with prefrontal damage often are described as blind to the future consequences of their decisions, and inclined to ‘live in the here and now’, little is known as to how the prefrontal cortex mediates past and future mental time travel. Method: Nine patients with prefrontal lesions and nine healthy controls generated past and future events in response to different time periods. Event transcriptions were scored using the Autobiographical Interview protocol (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002), which provides a reliable system for categorizing internal (episodic) and external (semantic) information. For each event, participants answered a series of questions to assess self‐reported phenomenal characteristics. Results: Patients with prefrontal lesions exhibited deficits in both remembering past events and imagining future events by generating fewer internal details than controls. This effect of group was larger in the past condition than in the future condition. In contrast, no group differences were seen in the number of external details, which were at the same level for patients and controls for both temporal conditions. There were no group differences in ratings of phenomenal characteristics. Conclusion: Our findings suggest that damage to prefrontal structures adversely affects the retrieval of past and the construction of future events. In particular, prefrontal structures are critical for the production of episodic event‐specific details when engaging in past and future mental time travel. [ABSTRACT FROM AUTHOR]

Converging evidence suggests that autobiographical memory and episodic future thinking share a common neurocognitive basis. Although previous research has shown that traumatic brain injury ( TBI) can impair the ability to remember the personal past, episodic future thinking has not previously been systematically examined within this population. In this study, we examined the ability to remember events in the personal past and the ability to imagine possible events in the personal future in a sample of moderate-to-severe TBI patients. We present data on nine patients and nine healthy controls, who were asked to report a series of events that had happened to them in the past and a series of events that might happen to them in the future. Transcriptions were scored according to a reliable system for categorizing internal (episodic) and external (semantic) information. For each event described, participants also completed two modified Autobiographical Memory Questionnaire items to assess self-reported phenomenal qualities associated with remembering and imagining. In addition, TBI patients underwent neuropsychological assessment. Results revealed that TBI patients recalled/imagined proportionally fewer episodic event-specific details for both past and future events compared to healthy controls (η2p = 0.78). In contrast, there were no group differences in ratings of phenomenal characteristics. These results are discussed in relation to theories suggesting that remembering and imagining the future are the expression of the same underlying neurocognitive system. [ABSTRACT FROM AUTHOR]