Effects on Memory of Early Testing and Accuracy Assessment for Central and Contextual Content

Memory for an event is influenced by many factors including retention interval, frequency of assessment, and type of information assessed concerning the event. We examined the usefulness of observer memory for contextual information in assessing accuracy of memory for central information. Participants viewed a video of a purse being stolen and were asked questions concerning the perpetrator and surrounding context of the event, including where and when the event occurred and who else was present. Participants tested immediately after seeing the video exhibited better memory than those tested for the first time 48-hour after the event. Additionally, testing immediately after viewing the video reduced forgetting over the 48-hour delay (i.e., early testing attenuated subsequent forgetting). Moreover, memory for the context of the event correlated positively with memory of the central information (i.e., perpetrator), and memory concerning other people at the event tended to have the highest correlation with perpetrator memory.

Hallucinations in a Patient with Alzheimer's Disease During the COVID-19 Crisis: A Case Study

While social distancing may be deemed necessary in order to avoid COVID-19 infections, the lockdown may impact mental health of patients with Alzheimer’s disease (AD). We present a case study involving hallucinations in a patient with AD who lives in a nursing home during the COVID-19 crisis. We compared this patient’s hallucination scores before and during the lockdown. We observed increased hallucinations during, compared to before, the lockdown. These increased hallucinations can be attributed to a number of elements such as the decreased in daily activities, social distancing, lack of physical contact with family members, and loneliness during the lockdown.

Smell your self: Olfactory stimulation improves self-concept in Alzheimer's disease

Research has demonstrated a link between decline in autobiographical memory and decline in the sense of self in Alzheimer's disease (AD). Recent work has also shown that odour is a powerful cue to alleviate decline in autobiographical memory in AD. Based on these findings, we investigated whether odour exposure improves access to self-concept in AD patients. To this end, we invited AD and control participants to make self-related statements (i.e., statements in response to the question "Who am I?") after odour exposure or without odour exposure. We measured the number and the categories of self-related statements (i.e., whether these statements described the psychological, social or physical self) that were generated in each condition. Results demonstrated that both AD and control participants generated more self-statements in the odour condition than in the odor-free condition, especially psychological self-statements. This study is the first to demonstrate the positive influence of olfactory stimulation on the retrieval of self-related knowledge in AD.

Better Destination Memory in Females

Destination memory refers to the ability to remember to whom one has sent information. The current study investigated gender differences in destination memory. Female and male participants were asked to tell proverbs to pictures depicting faces of female and male celebrities. Participants were later asked to decide to whom each proverb had been previously told. Results showed better destination memory (regardless of the destination’s gender) in female participants than in male participants, a performance that was significantly correlated with verbal episodic memory. However, no own-gender bias was observed, as both female and male participants demonstrated similar memory for female and male destinations. Taken together, our findings suggest a relationship between females’ superiority in destination memory and their better verbal episodic memory. The absence of an own-gender bias in destination memory is interpreted an evolutionary need to maintain social contacts with all genders.

Memories Supporting Myself: Autobiographical Memory Supports Self-Continuity in Alzheimer's Disease

We investigated, for the first time, how people with mild Alzheimer's disease (AD) reflect on continuity of their self (i.e., whether they are the same person they were before). We invited people with mild AD and control participants to conduct The Thinking about Life Experiences (TALE) Scale. More specifically, we invited participants to indicate whether they think about their life story: when they want to feel that they are the same person that they were before (Item 1), when they are concerned about whether they are still the same type of person that they were earlier (Item 2), when they are concerned about whether their values have changed over time (Item 3), when they are concerned about whether their beliefs have changed over time (Item 4), and when they want to understand how they have changed from who they were before (Item 5). The scores of people with AD and control participants on the items of the TALE scale were similar, except for the first item on which people with AD provided higher scores than did control participants. As demonstrated by scores on Item 1, people with mild AD can retrieve autobiographical memories to reflect on situations in which they want to feel that they are the same person that they were before. In other words, people with mild AD can draw on their personal and meaningful events to maintain a continuous sense of self or even to reflect on situations in which they are concerned about their self-continuity.

High depression and anxiety in people with Alzheimer's disease living in retirement homes during the covid-19 crisis

To cope with Covid-19 and limits its spread among residents, retirement homes have prohibited physical contact between residents and families and friend and, in some cases, even between residents or between residents and caregivers. We investigated the effects of measures against Covid-19 on the mental health of participants with Alzheimer's disease (AD) who live in retirement homes in France. We instructed on-site caregivers to assess depression and anxiety in participants with mild AD who live in retirement homes. Fifty-eight participants consented to participate in the study. The participants rated their depression and anxiety during and before the Covid-19 crisis. Participants reported higher depression (p = .005) and anxiety (p = .004) during than before the Covid-19 crisis. These increases can be attributed to the isolation of the residents and/or to the drastic changes in their daily life and care they receive. While, in their effort to prevent infections, retirement homes are forced to physically separate residents from the outside world and to drastically reduce residents' activities, these decisions are likely to come at a cost to residents with AD and their mental health.

Eye movements of recent and remote autobiographical memories: fewer and longer lasting fixations during the retrieval of childhood memories

There is an increased interest in the study of eye movements during the retrieval of autobiographical memories. Following this trend, the aim of the current study was to evaluate eye movements during the retrieval of remote and recent autobiographical memories. We instructed 71 participants to retrieve memories of personal events from early childhood (6-10 years), late childhood/early adolescence (11-14 years), late adolescence (15-18 years), and the last month. During the retrieval of these memories, participants wore eye-tracking glasses. Analyses showed that early childhood memories triggered fewer fixations and fixations with longer durations than memories from the last month. However, no significant differences were observed for the number of saccades, saccade durations, or total amplitude of the saccades. The fewer and longer lasting fixations during the retrieval of early childhood memories can be attributed either to the visual system reconstructing remote memories from an observer perspective or to difficulties when reconstructing remote memories.

Self-defining Memories and their Contribution to the Sense of Self in Alzheimer's Disease

AIMS

Unlike autobiographical memory (i.e., memory for personal information) in Alzheimer's Disease (AD), little is known about Self-Defining Memories (SDM) (i.e., memories of highly significant personal events) in AD.

METHODS

The characteristics of self-defining memories in AD were evaluated by analyzing their specificity, emotional valence, and integration, as well as their centrality and contribution to self-continuity. Results demonstrated fewer specific SDM in AD participants than in controls.

RESULTS

No significant differences were observed between AD participants and controls regarding the production of positive or integrated SDM. Furthermore, no significant differences were observed between AD participants and controls regarding the rating of the centrality of SDM and their contribution to self-continuity. These results demonstrate that, although AD participants produce fewer specific SDM than controls, both populations have similar levels of emotional valence, integration, centrality, and selfcontinuity of these memories.

CONCLUSION

It is concluded that patients with AD, at least those in the mild stages of the disease, can build on significant personal events and experiences (i.e., SDM) to reflect on how these events have changed the way they see themselves.

Social commitment toward prospective memory tasks in cognitively impaired non-demented individuals

Prospective memory, which is the ability to remember to perform an intended action in the future, has been found to be diminished in cognitively impaired non-demented individuals (CIND). This study investigated whether providing CIND with a social motive would improve their prospective memory performance. Accordingly, CIND and controls were asked to perform a prospective memory task which includes one of the following three conditions: a reward (i.e., a candy bar), no feedback, or a social motive (i.e., that performing the prospective memory task would be a favor for the experimenter). The participants also rated their commitment to achieve the three prospective conditions. Results showed lower prospective memory in CIND than in controls. Unlike controls, CIND did not benefit from the social motive; however, both populations demonstrated commitment toward this condition relative to the "reward" or "control" conditions. Although social motivation did not ameliorate prospective memory, CIND seem to demonstrate commitment to perform prospective memory tasks that involve social benefits for others.

Pupil dilation as an indicator of future thinking

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.

Hallucinations in Older Adults: A Practical Review

Older adults experience hallucinations in a variety of social, physical, and mental health contexts. Not everyone is open about these experiences, as hallucinations are surrounded with stigma. Hence, hallucinatory experiences in older individuals are often under-recognized. They are also commonly misunderstood by service providers, suggesting that there is significant scope for improvement in the training and practice of professionals working with this age group. The aim of the present article is to increase knowledge about hallucinations in older adults and provide a practical resource for the health and aged-care workforce. Specifically, we provide a concise narrative review and critique of (1) workforce competency and training issues, (2) assessment tools, and (3) current treatments and management guidelines. We conclude with a brief summary including suggestions for service and training providers and future research.

Attractive memory: High destination memory for attractive faces

Research has demonstrated that destination memory (i.e., the ability to remember to whom information was previously told) can be influenced by characteristics (e.g., emotional expressions and age) of the destination. Building on this literature, we investigated whether destination memory can be influenced by the attractiveness of the destination. We invited participants to give information on attractive faces, unattractive faces, or neither-attractive-nor-unattractive faces. On a recognition test, they were invited to decide to whom each piece of information had been previously told. Results demonstrated higher destination memory (1) for attractive faces than for neither-attractive-nor-unattractive faces, and (2) for unattractive faces than for neither-attractive-nor-unattractive faces. We attribute the higher destination memory for attractive and unattractive destinations to their distinctiveness compared with neutrally attractive destinations. We also provide some attentional explanations for the high memory for attractive and unattractive destinations.

Singles and Faces: High Recognition for Female Faces in Single Males

A substantial body of research has assessed the effect of gender on face recognition; however, little is known about the effect of relationship status on face recognition. In this study, we assessed for the first time how relationship status impacts face recognition by asking 62 male and female participants to decide whether they had previously encountered faces of males and females. Participants were also asked to fill a socio-demographic variables questionnaire which included, among other information, question about their relationship status (i.e., single vs. in a relationship). A significant effect of relationship status on face recognition was observed only in males; namely, single males demonstrated higher face recognition than males in relationships, whereas similar face recognition was observed in single and in-relationship females. More specifically, single males demonstrated higher recognition for female than for male faces, whereas no differences were observed in single females, males in relationships, or in females in relationship. Single males seem to be motivated by mating opportunity and, thus, unlike single females or males and females in relationships, devote high attentional resources to processing faces of the opposite gender.  

The discounted future: Relationship between temporal discounting and future thinking in Alzheimer's disease

Temporal discounting refers to the tendency to prefer smaller sooner rewards over larger later rewards. Prior research has reported temporal discounting in Alzheimer's disease (AD). We thus investigated, in this study, the relationship between temporal discounting and future thinking in AD. The study included 40 patients with AD and 42 control participants. We invited participants, on a temporal discounting task, to choose between an immediate but smaller or a delayed but larger amount of money (e.g. "would you prefer 10 dollars today or 50 dollars after one month?"). We also invited the participants to imagine events that may happen in the future, a task known as future thinking. Analysis demonstrated a bias toward immediate rewards (i.e. temporal discounting) as well as difficulties to imagine specific future events in patients with AD. Critically, temporal discounting and future thinking in AD were significantly correlated. Generally speaking, a lack of thinking about the future may lead to impulsive behavior. More specifically, decline in future thinking in AD may limit the ability of patients to project themselves in time to consider outcomes of their decisions, resulting in a tendency to devaluate future rewards in favor of more imminent ones (i.e. temporal discounting).

The subjective experience of mind wandering in Alzheimer's disease

Introduction: Little is known about mind wandering in Alzheimer's disease (AD). In this study, we evaluated the subjective experience of mind wandering in AD.Methods: We invited AD patients and control participants to rate the occurrence, intentionality, emotionality, visual imagery, specificity, self-relatedness and temporal orientation of mind wandering.Results: Analysis showed that AD patients rated their mind wandering as more frequent, negative, and more oriented toward the past, but less vivid and specific than that of control participants. No significant differences were observed between AD patients and control participants regarding the intentionality or self-relatedness of mind wandering.Conclusions: These findings demonstrate the negative content in AD. Regarding the reduction of visual imagery and specificity during mind wandering, this reduction may mirror a diminished subjective experience of mind wandering in AD. Regarding temporality, our results may reflect a tendency of AD patients to reminisce over past experiences. Finally, mind wandering in AD seems to trigger significant self-related content.

The thin line between reality and imagination: The imagination inflation effect in Korsakoff's syndrome

OBJECTIVE

The imagination inflation effect, which is a form of memory distortion, occurs when imagining an event that never happened may increase the tendency to falsely remember that it really occurred. We investigated this effect in Korsakoff's syndrome.

METHOD

Our procedures consisted of 2 sessions and a recognition test. In Session 1, patients with Korsakoff's syndrome and controls listened to statements of actions (e.g., "hold the pen"), enacted the actions, or imagined performing the actions. In Session 2, participants imagined statements of actions from Session 1 as well as new statements of actions once or 3 times. On the recognition test, participants had to decide whether statements of actions were or were not enacted during Session 1.

RESULTS

Analysis demonstrated that imagining performing the actions increased the tendency of both patients with Korsakoff's syndrome and controls to falsely recall the actions as having been enacted.

DISCUSSION

Our findings suggest that patients with Korsakoff's syndrome are prone to the imagination inflation effect, an effect that can be attributed to difficulties with source monitoring. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Memory of decisions: Relationship between decline of autobiographical memory and temporal discounting in Alzheimer's disease

Temporal discounting refers to the tendency to attribute higher value to a reward received early than to one received later. We evaluated this tendency in patients with Alzheimer's Disease. We also evaluated whether temporal discounting is associated with decline in autobiographical memory (i.e., the ability to remember past personal experiences), with executive dysfunction, and/or with general cognitive decline. We invited patients with AD and control participants to answer binary questions involving the choice between receiving a smaller amount of money earlier or a larger one later (e.g., "Which do you prefer, 10 euros in cash right now or 50 euros in a month?"). Results demonstrated higher temporal discounting in patients with AD than in control participants. Temporal discounting was significantly correlated with decline in AM and general cognitive decline but not with executive dysfunction in patients with AD. The tendency to decide based on immediate rewards (i.e., temporal discounting) in AD is related with difficulty in remembering information about experiences of previous decisions, and/or their consequences (i.e., decline in autobiographical memory).

Effects of Olfactory Stimulation on Past and Future Thinking in Alzheimer’s Disease

Several studies have demonstrated that Alzheimer’s disease (AD) is associated not only with difficulty in remembering past events but also with a compromised ability to imagine future ones. Recent empirical research has also demonstrated that odor is an effective cue to alleviate difficulty in remembering past events in AD. We investigated whether odor exposure would help AD patients to imagine future events. To this end, we invited AD patients and control participants to evoke past and future events after odor exposure or without odor. Analysis showed that AD patients and control participants produced more specific and more emotional past and future events after odor exposure than without odor. However, odor exposure did not improve the retrieval time for future thinking in AD participants. This study is the first to demonstrate positive effects of odor exposure on the ability of AD patients to project themselves into the future.

Chunking to improve verbal forward spans in Korsakoff's syndrome

Chunking is a mnemonic strategy that involves organizing information into appropriate units. Our article examined the use of this strategy on forward and backward span performance in Korsakoff's syndrome. Fifteen patients with Korsakoff's syndrome and 17 age-and-education matched healthy controls participated to the study. Digit span performance (both forward and backward) was tested before and after chunking training. Results demonstrated an increased performance on the forward spans after chunking training in the patients with Korsakoff's syndrome, but no beneficial effect was observed on the backward spans in these participants. Controls demonstrated a chunking effect on both forward and backward span performance. Our findings suggest that a simple training in chunking may be useful as part of a cognitive strategy training for improving working memory performance in patients with Korsakoff's syndrome.

Confabulations on Time: Relationship between Confabulations and Timing Deviations in Alzheimer’s Disease

Objectives

We investigated the relationship between confabulations and the ability to process chronological characteristics of memories in Alzheimer’s Disease (AD).

Methods

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.

Results

We observed significant positive correlations between provoked/spontaneous confabulations and deviations in time estimation on the time perception task.

Conclusions

These findings demonstrate a relationship between confabulations in AD and difficulties in processing the chronological characteristics of elapsed events.

"What" and "How": A New Perspective for Understanding Unawareness in Alzheimer's Disease Through a Combination of Two Perspectives

OBJECTIVES

Assessments of unawareness in Alzheimer's disease mainly focus on the objects (the "what") of unawareness. A recent person-centered approach proposes to also assess the processes (the "how"). The present study combines 2 approaches to understand this heterogeneity in assessments of unawareness.

METHOD

We recruited 46 participants from 8 nursing homes. They underwent a semi-structured interview and were assessed using a prediction-performance paradigm. Spearman correlations were calculated, and generalized additive models were established.

RESULTS

The 2 approaches are associated through cognitive deficits, confrontation with difficulties and identity changes. Objects (the what), mechanisms, and modes of expression (the how) explain at least 29.6% of the variance of unawareness.

CONCLUSIONS

Unawareness is more than simply being unaware of something; it is a synergy between the objects and processes of arousal and expression. Moreover, unawareness extends beyond the disease to include the self. Considering the entire person seems to be necessary.

The Swinging Self: The Costs of Shifting Between Self-Images in Alzheimer's Disease

BACKGROUND

We investigated the ability of patients with Alzheimer's disease (AD) to shift between different self-images.

METHODS

We developed an original task (shifting-self task) in which we invited 28 patients with AD and 30 control participants to generate "who am I" statements that describe 2 alternative self-images (ie, physical-self vs psychological-self). In a control task, participants had to generate 2 blocks of "who am I" statements (ie, physical-self block and psychological-self block).

RESULTS

Analyses showed longer completion time in both the shifting-self and control task in patients with AD than in control participants. Completion time on the shifting-self task was longer than that on the control task in patients with AD, suggesting a shifting cost in AD.

CONCLUSION

We propose that one feature of the diminished sense of self in AD is the difficulty of patients to shift between different alternating self-images.