The days we never forget: Flashbulb memories across the life span in Alzheimer's disease.

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.

Autobiographical memory loss in Alzheimer's disease: The role of the reminiscence bump.

Research on autobiographical memory loss in Alzheimer's disease (AD) is characterized by conflicting findings concerning a possible sparing of older memories. The literature shows evidence for both a negative temporal gradient, a flat gradient and a reminiscence bump - that is, a disproportionally high frequency of memories from early adulthood relative to surrounding periods. Here, we expanded the number of lifetime periods of the Autobiographical Memory Interview (AMI; Kopelman, Wilson & Baddeley, 1989, 1990) from the standard three to seven in order to increase the sensitivity of the test to variations in the temporal distribution of autobiographical memories across the life span. Twenty-five older adults diagnosed with AD (MMMSE = 21.16, SD = 5.08) and a matched sample of 30 healthy, older adults were assessed. The temporal distribution for personal semantic information in AD showed a temporal gradient steadily decreasing from middle childhood to present life, consistent with predictions derived from consolidation theories. In comparison, the temporal distribution of incidents/episodic memories produced by AD patients in response to the expanded AMI showed a predominance of autobiographical memories from age 6 to 30, followed by a steep drop in memory referring to events that had occurred after age 30. This distribution challenges standard theories of retrograde amnesia in AD by showing neither a temporal gradient, decreasing progressively from early to later life, nor a flat gradient. In contrast, the distribution is consistent with the reminiscence bump identified in autobiographical memory research. Schematization and retrieval support provided by cultural life scripts are discussed.

Watering Memory Trees.

Along with the rising number of people suffering from dementia and Alzheimer's disease (due to longer life spans) come two main concerns: finding remedies and helping them live comfortable and contented lives. Our authors examine the latest research on what is called "retro environments" and "reminiscence therapy," which includes health-care communities that offer elements of nostalgia, as well as music, objects, and photographs from one's past.

Five weeks of immersive reminiscence therapy improves autobiographical memory in Alzheimer's disease.

We examined the effects of a new Immersive Reminiscence Therapy (IRT) programme on cognitive function, including autobiographical memory, in a sample Alzheimer's disease (AD) patients. A total of 43 AD patients with mild to moderate disease severity were randomly assigned to either an intervention group (n = 22, MMMSE = 20.77), or a control group (n = 21, MMMSE = 19.24). The intervention group received one weekly group-based session of IRT for five weeks in an authentic 1950s style museum environment, matching the time of the participants' youth. IRT included semi-structured conversations about the past. The control group received standard care. We assessed performance on cognitive function and autobiographical memory at baseline and post-intervention. Five weeks of IRT enhanced subsequent autobiographical memory performance, when participants were cued by concrete objects dated to their youth. Object-cued memories reported post intervention included a significantly higher degree of episodic details and higher word counts. The intervention showed no effect on the Autobiographical Memory Interview or word-cued recall. Global cognitive function and semantic autobiographical memory performance increased across time for both groups. Our findings demonstrate that immersion into a setting, rich on concrete cues dated to the participants' youth can improve autobiographical remembering.

The life span distribution of autobiographical memory in Alzheimer's disease.

OBJECTIVE: The literature on the temporal distribution of autobiographical memory in Alzheimer's disease (AD) is characterized by mixed findings concerning the presence of a temporal gradient in the loss of autobiographical memory. Some studies show a gradient, implying better access to more remote autobiographical memories, whereas others do not. These conflicting results likely reflect differences in the test methodologies, accentuating the need for replications and extensions. METHOD: Forty-five older adults diagnosed with AD (via Mini-Mental State Examination, M = 19.89, SD = 4.05) and a matched sample of 44 healthy older adults were assessed on two different autobiographical memory measures: the Autobiographical Memory Interview (Kopelman, Wilson, & Baddeley, 1990) and the Galton-Crovitz task (word and object cueing) to examine the temporal distribution of personal autobiographical memories across the life span. RESULTS: The impairment of episodic and personal semantic remembering, as indexed by the Autobiographical Memory Interview, was associated with a negative temporal gradient with better preservation of memories from the remote past, relative to the recent one. The results from the word- and object-cueing task replicated the finding that AD is associated with markedly impaired recall of recent events. In addition, both groups showed a peak in the recollection of events from middle childhood and adolescence, consistent with research on the reminiscence bump. CONCLUSIONS: Older adults diagnosed with AD demonstrate increased recollection of personal semantic and episodic events from the remote past relative to the recent one. The findings are discussed in relation to prominent models of memory consolidation. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A short cut to the past: Cueing via concrete objects improves autobiographical memory retrieval in Alzheimer's disease patients.

Older adults diagnosed with Alzheimer's disease (AD) have difficulties accessing autobiographical memories. However, this deficit tends to spare memories dated to earlier parts of their lives, and may partially reflect retrieval deficits rather than complete memory loss. Introducing a novel paradigm, the present study examines whether autobiographical memory recall can be improved in AD by manipulating the sensory richness, concreteness and cultural dating of the memory cues. Specifically, we examine whether concrete everyday objects historically dated to the participants' youth (e.g., a skipping rope), relative to verbal cues (i.e., the verbal signifiers for the objects) facilitate access to autobiographical memories. The study includes 49 AD patients, and 50 healthy, older matched control participants, all tested on word versus object-cued recall. Both groups recalled significantly more memories, when cued by objects relative to words, but the advantage was significantly larger in the AD group. In both groups, memory descriptions were longer and significantly more episodic in nature in response to object-cued recall. Together these findings suggest that the multimodal nature of the object cues (i.e. vision, olfaction, audition, somatic sensation) along with specific cue characteristics, such as time reference, texture, shape, may constrain the retrieval search, potentially minimizing executive function demands, and hence strategic processing requirements, thus easing access to autobiographical memories in AD.

[Reminiscence therapy may increase subjective well-being in persons with dementia].

Reminiscence therapy is a popular psychosocial method in dementia care aiming at increasing subjective well-being through sharing memories from one's personal past. This article summarizes findings from the past decades of research based on three reviews which, despite mixed findings, methodological inconsistencies and conceptual vagueness in the field, overall report reminiscence therapy to be a potentially effective psychosocial intervention with regard to increasing subjective well-being.

Executive semantic processing is underpinned by a large-scale neural network: revealing the contribution of left prefrontal, posterior temporal, and parietal cortex to controlled retrieval and selection using TMS.

To understand the meanings of words and objects, we need to have knowledge about these items themselves plus executive mechanisms that compute and manipulate semantic information in a task-appropriate way. The neural basis for semantic control remains controversial. Neuroimaging studies have focused on the role of the left inferior frontal gyrus (LIFG), whereas neuropsychological research suggests that damage to a widely distributed network elicits impairments of semantic control. There is also debate about the relationship between semantic and executive control more widely. We used TMS in healthy human volunteers to create "virtual lesions" in structures typically damaged in patients with semantic control deficits: LIFG, left posterior middle temporal gyrus (pMTG), and intraparietal sulcus (IPS). The influence of TMS on tasks varying in semantic and nonsemantic control demands was examined for each region within this hypothesized network to gain insights into (i) their functional specialization (i.e., involvement in semantic representation, controlled retrieval, or selection) and (ii) their domain dependence (i.e., semantic or cognitive control). The results revealed that LIFG and pMTG jointly support both the controlled retrieval and selection of semantic knowledge. IPS specifically participates in semantic selection and responds to manipulations of nonsemantic control demands. These observations are consistent with a large-scale semantic control network, as predicted by lesion data, that draws on semantic-specific (LIFG and pMTG) and domain-independent executive components (IPS).

The neural organization of semantic control: TMS evidence for a distributed network in left inferior frontal and posterior middle temporal gyrus.

Assigning meaning to words, sounds, and objects requires stored conceptual knowledge plus executive mechanisms that shape semantic retrieval according to the task or context. Despite the essential role of control in semantic cognition, its neural basis remains unclear. Neuroimaging and patient research has emphasized the importance of left inferior frontal gyrus (IFG)--however, impaired semantic control can also follow left temporoparietal lesions, suggesting that this function may be underpinned by a large-scale cortical network. We used repetitive transcranial magnetic stimulation in healthy volunteers to disrupt processing within 2 potential sites in this network--IFG and posterior middle temporal cortex. Stimulation of both sites selectively disrupted executively demanding semantic judgments: semantic decisions based on strong automatic associations were unaffected. Performance was also unchanged in nonsemantic tasks--irrespective of their executive demands--and following stimulation of a control site. These results reveal that an extended network of prefrontal and posterior temporal regions underpins semantic control.