Recent studies suggest that common cognitive processes and neuroanatomical substrates underlie the ability to remember the past and imagine the future. We studied these cognitive processes in ...patients with Alzheimer's Disease (AD). We asked 27 participants with AD and 30 older controls, matched by age, sex, and educational level, to generate past and future autobiographical events. Autobiographical generation was analyzed with respect to theme, general autobiographical performance, contextual performance, self-defining memories, and autonoetic reliving/re-experiencing. Unlike older controls, most AD participants evoked similar themes when generating past and future events (n=23/30 participants). These participants also showed similar autobiographical and contextual performance, similar amount of self-defining memories, and similar autonoetic states when generating past and future events. Further, significant correlations were detected between hippocampal-dependent memory decline in AD participants and their ability to relive past and future events. These outcomes suggest striking similarities between remembering the past and imagining the future in AD. Due to their memory decline, imagining the future in AD patients is likely to draw heavily from the little amount of available information from past episodes, resulting in striking similarities between remembering the past and imagining the future. Finally, and unlike AD participants, older controls mentally “try out” alternative approaches to upcoming situations without replicating the same schemes of past events.
•When generating past and future events, AD participants evoked similar themes.•When generating past and future events, AD participants provided similar amount of contextual details and self-defining themes.•In AD participants, episodic memory performance is associated with the ability to relive past and future events.•In future thinking, control adults showed wider range of themes and cognitive flexibility.
Background
The “time perspectives theory” describes how individuals emphasize some time frames over others (e.g., present vs. future) and thus create their unique approach to time perception. ...Building on this theory, we investigated three time orientations in Alzheimer’s disease (AD): (1) present-hedonistic orientation, which focuses on current sensations and pleasures without considering the future, (2) present-fatalistic orientation, characterized by a bias of hopelessness and helplessness toward the future, and (3) future orientation, which focuses on achieving personal goals and future consequences of present actions.
Methods
Participants with mild AD (
n
= 30) and controls (
n
= 33) were assessed with a questionnaire regarding time perspectives and a questionnaire of depression.
Results
Results demonstrated low future orientation and high present-fatalistic orientation in AD participants, whereas older adults demonstrated the reverse pattern. Depression positively correlated with fatalistic-present orientation, but negatively correlated with hedonistic-present and future orientations.
Discussion
Although our findings are preliminary and the sample size is small, depression in mild AD seems to be related with a fatalistic orientation toward the present, as well as a hopeless and helpless perspective on the future, an orientation that results in little desire to enjoy the present.
Abstract
Objective
Because memory decline is the hallmark of Alzheimer’s disease (AD), an important endeavor for both clinicians and researchers is to improve memory performances in AD. This can be ...pursued by olfactory stimulation of memory in patients with AD and by studying the effects of olfactory stimulation on autobiographical memory (i.e., memory for personal information). The effects of olfactory stimulation on autobiographical memory in patients with mild AD have been reported by recent research. We thus provide the first comprehensive overview of research on odor-evoked autobiographical memory in AD. We also establish the basis for solid theoretical analysis concerning the memory improvement reported by research on odor-evoked autobiographical memory in AD.
Method
We examined literature on odor-evoked autobiographical memories in AD and propose the “OdAMA” (Odor-evoked Autobiographical Memory in Alzheimer’s disease) model.
Results and discussion
According to OdAMA model, odor exposure activates involuntary access to specific autobiographical memories, which promotes enhanced experience subjective of retrieval in patients with AD and improves their ability to construct not only recent and remote events but also future ones. The OdAMA model could serve as a guide for researchers and clinicians interested in odor-evoked autobiographical memory in AD.
Alzheimer's disease (AD) has been associated with autobiographical overgenerality (i.e. a tendency of patients to retrieve general rather than specific personal memories). AD has also been associated ...with hallucinations. We investigated the relationship between autobiographical overgenerality and hallucinations in AD.
We invited 28 patients with mild AD to retrieve autobiographical memories, and we also evaluated the occurrence of hallucinations in these patients.
Analysis demonstrated significant correlations between hallucinations and autobiographical overgenerality in the patients.
AD patients who are distressed by hallucinations may demonstrate autobiographical overgenerality as a strategy to avoid retrieving distressing information that may be related with hallucinations. However, hallucinations as observed in our study can be attributed to other factors such as the general cognitive decline in AD.
Within the field of memory research, studies on destination memory (e.g., the ability to remember to whom information was previously told) show how it is closely associated with social cognition. The ...present review thus summarizes the literature on destination memory and demonstrates how it involves social interaction. It offers a comprehensive picture of the many factors that may influence destination memory and distinguishes factors related to the recipient (e.g., familiarity, emotional states, and distinctiveness/attractiveness) and sender of information (e.g., the sender's extroversion) in social communications. It suggests that destination memory involves the ability of the sender to infer the cognitive/affective state of the recipient and to attribute the output message to a recipient-related stereotype. Extrovert senders may also easily remember the destination as they typically value social communication, public sharing and processing of social information. Destination memory also involves features such as familiarity, age, emotional state, distinctiveness, and attractiveness of the recipient. By offering a comprehensive framework of how destination memory functions in everyday life interactions, the present review shows how destination memory is intimately associated with communicative efficacy and social interactions.
The junction between memory dysfunction and socioaffective dysfunction is a complex area as research has typically been interested in one dysfunction rather than in the other. However, this junction ...can be studied under the lens of destination memory. Destination memory (i.e. the ability to remember to whom a piece of information was previously transmitted) is unique in that it draws on both memory and socioaffective processes. Research has demonstrated how destination memory is prone to distortions in neurological/psychiatric disorders. This paper aims to provide a focused review on the interplay between memory and socioaffective processes in the deterioration of destination memory within these disorders. It shows how both episodic memory and socioaffective dysfunction can jointly contribute to the decline in destination memory, although the contribution of each of the two factors may vary depending on the disorder.
Although the integrative memory model proposed by Bastin et al. is interesting, particularly for Alzheimer's disease, it may benefit from incorporating the subjective experience of recollection. We ...therefore offer complementary lines of interpretation to explain how recollection and familiarity in Alzheimer's disease can be dissociated based not only on accounts of their neural correlates but, critically, on the subjective experience of memory in patients.
We investigated the relationship between confabulations and the ability to process chronological characteristics of memories in Alzheimer's Disease (AD).
We evaluated provoked confabulations, ...spontaneous confabulations, and time perception in 31 AD patients. We evaluated provoked confabulations with questions probing general and personal knowledge. We evaluated spontaneous confabulations with a scale rated by nursing and medical staff. Regarding time perception, we invited the participants to perform a simple ongoing activity (i.e., deciding whether words were abstract or concrete), in order to provide a verbal estimation of the elapsed time intervals.
We observed significant positive correlations between provoked/spontaneous confabulations and deviations in time estimation on the time perception task.
These findings demonstrate a relationship between confabulations in AD and difficulties in processing the chronological characteristics of elapsed events.
Background
The pupil typically dilates in reaction to cognitive load. In this study, we, for the first time, investigated whether future thinking (i.e., the ability to generate hypothetical scenarios ...in the future) would result in pupil dilation.
Methods
We recorded pupil dilation of participants during two conditions: past and future thinking. In past thinking, we invited participants to retrieve past personal events, while in future thinking, we invited them to imagine an event that may occur in the future.
Results
Analysis demonstrated a larger pupil size during future than past thinking. Results also demonstrated longer retrieval time of future events compared with past ones, suggesting that future thinking perhaps requires more cognitive load than for past thinking. Interestingly, retrieval times during past and future thinking were positively correlated with pupil size.
Discussion
The finding that future thinking activates pupil dilation could be due to the fact that while both past and future thinking require retrieving information from memory, future, but not past, thinking additionally requires the ability to recombine this information into novel scenarios.
Self-imagination refers to a mnemonic strategy of imagining oneself at a scene related to a cue.
We tested the effect of self-imagination on memory recall in Alzheimer's disease (AD) Methods: ...Individuals with AD and healthy controls were invited to perform two conditions. In the control (i.e., semantic elaboration) condition, participants were asked to define to which semantic category (e.g., dance) words (e.g., waltz) belong. However, in a self-imagining condition, participants were asked to imagine themselves in a scene related to the stimuli (e.g., dancing waltz). Both conditions were followed by two free memory tests with two different intervals (20 seconds vs. 20 minutes).
Analysis showed a beneficial effect of self-imagination for the 20-second but not for the 20- minute recall in AD participants and controls.
Clinicians can incorporate our findings when assessing, especially when trying to rehabilitate, episodic memory in AD.
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