Multifactorial Memory Questionnaire: a comparison of young and older adults.

The Multifactorial Memory Questionnaire (MMQ; Troyer & Rich, [2002]. Psychometric properties of a new metamemory questionnaire for older adults. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 57(1), P19-P27) is a widely used measure of subjective memory consisting of three scales: Satisfaction, Ability, and Strategies. Although subjective memory complaints are prevalent across different age groups, the factor structure and psychometric properties of the MMQ have yet to be examined in young adults. Here, we independently replicated the original MMQ factor structure in N = 408 young adults (YA) recruited from undergraduate courses and N = 327 older adults (OA) and, for the first time, assessed the age-invariance of the scale using measurement invariance testing. YAs made significantly higher ratings than OAs on MMQ-Satisfaction and MMQ-Strategies, indicating greater satisfaction with their memory and greater use of strategies, but the groups were similar on MMQ-Ability. The original MMQ factor structure was replicated in OAs but not in YAs, and age invariance was not supported. Future studies seeking to compare young and older adults could therefore consider either requesting modification of the MMQ for use with young adults or using a different scale.

Generalization of memory-related brain function in asymptomatic older women with a family history of late onset Alzheimer's Disease: Results from the PREVENT-AD Cohort.

Late-onset Alzheimer's disease (AD) disproportionately affects women compared to men. Episodic memory decline is one of the earliest and most pronounced deficits observed in AD. However, it remains unclear whether sex influences episodic memory-related brain function in cognitively intact older adults at risk of developing AD. Here we used task-based multivariate partial least squares analysis to examine sex differences in episodic memory-related brain activity and brain activity-behavior correlations in a matched sample of cognitively intact older women and men with a family history of AD from the PREVENT-AD cohort study in Montreal, Canada (Mage=63.03±3.78; Meducation=15.41±3.40). We observed sex differences in task-related brain activity and brain activity-behavior correlations during the encoding of object-location associative memories and object-only item memory, and the retrieval of object only item memories. Our findings suggest a generalization of episodic memory-related brain activation and performance in women compared to men. Follow up analyses should test for sex differences in the relationship between brain activity patterns and performance longitudinally, in association with risk factors for AD development. This article is part of the Virtual Special Issue titled COGNITIVE NEUROSCIENCE OF HEALTHY AND PATHOLOGICAL AGING. The full issue can be found on ScienceDirect at https://www.sciencedirect.com/journal/neurobiology-of-aging/special-issue/105379XPWJP.

APOE4 Status is Related to Differences in Memory-Related Brain Function in Asymptomatic Older Adults with Family History of Alzheimer's Disease: Baseline Analysis of the PREVENT-AD Task Functional MRI Dataset.

BACKGROUND: Episodic memory decline is one of the earliest symptoms of late-onset Alzheimer's disease (AD). Older adults with the apolipoprotein E ɛ4 (+APOE4) genetic risk factor for AD may exhibit altered patterns of memory-related brain activity years prior to initial symptom onset. OBJECTIVE: Here we report the baseline episodic memory task functional MRI results from the PRe-symptomatic EValuation of Experimental or Novel Treatments for Alzheimer's Disease cohort in Montreal, Canada, in which 327 healthy older adults were scanned within 15 years of their parent's conversion to AD. METHODS: Volunteers were scanned as they encoded and retrieved object-location spatial source associations. The task was designed to discriminate between brain activity related to spatial source recollection and object-only (recognition) memory. We used multivariate partial least squares (PLS) to test the hypothesis that +APOE4 adults with family history of AD would exhibit altered patterns of brain activity in the recollection-related memory network, comprised of medial frontal, parietal, and medial temporal cortices, compared to APOE4 non-carriers (-APOE4). We also examined group differences in the correlation between event-related brain activity and memory performance. RESULTS: We found group similarities in memory performance and in task-related brain activity in the recollection network, but differences in brain activity-behavior correlations in ventral occipito-temporal, medial temporal, and medial prefrontal cortices during episodic encoding. CONCLUSION: These findings are consistent with previous literature on the influence of APOE4 on brain activity and provide new perspective on potential gene-based differences in brain-behavior relationships in people with first-degree family history of AD.

Visual Event-Related Potentials in Mild Cognitive Impairment and Alzheimer's Disease: A Literature Review.

BACKGROUND: Cognitive deficits are correlated with increasing age and become more pronounced for people with mild cognitive impairment (MCI) and dementia caused by Alzheimer's disease (AD). Conventional methods to diagnose cognitive decline (i.e., neuropsychological testing and clinical judgment) can lead to false positives. Tools such as electroencephalography (EEG) offer more refined, objective measures that index electrophysiological changes associated with healthy aging, MCI, and AD. OBJECTIVE: We sought to review the EEG literature to determine whether visual event-related potentials (ERPs) can distinguish between healthy aging, MCI, and AD. METHOD: We searched Medline and PyscInfo for articles published between January 2005 and April 2018. Articles were considered for review if they included participants aged 60+ who were healthy older adults or people with MCI and AD, and examined at least one visually elicited ERP component. RESULTS: Our search revealed 880 records, of which 34 satisfied the inclusion criteria. All studies compared cognitive function between at least two of the three groups (healthy older adults, MCI, and AD). The most consistent findings related to the P100 and the P3b; while the P100 showed no differences between groups, the P3b showed declines in amplitude in MCI and AD. CONCLUSION: Visually elicited ERPs can offer insight into the cognitive processes that decline in MCI and AD. The P3b may be useful in identifying older adults who may develop MCI and AD, and more research should examine the sensitivity and specificity of this component when diagnosing MCI and AD.

Expectations may influence the effects of transcranial direct current stimulation.

Growing interest surrounds transcranial direct current stimulation (tDCS) as a safe and inexpensive method for improving cognitive functions and mood. Nevertheless, tDCS studies rarely examine psychological factors such as expectations of outcomes, which may influence tDCS responsiveness through placebo-like effects. Here we sought to evaluate the potential influence of expectations on tDCS intervention outcomes. We assessed expectations of tDCS outcomes in 88 healthy young adults on three occasions: i) at baseline; ii) after reading information implying either high or low effectiveness of stimulation; and iii) after a single-session of sham-controlled anodal tDCS applied to the left dorsolateral prefrontal cortex, during working memory (WM) training. Participants were largely uncertain about the effectiveness of stimulation in improving cognitive function at baseline. High or low expectation priming using simple positive or cautionary messages significantly increased or decreased expectation ratings, respectively, but ratings significantly decreased following stimulation in all groups. We found greater improvement in participants who received high compared to low expectation priming. Participants who received active stimulation and low expectation priming exhibited the lowest performance, suggesting that expectation priming and stimulation may have interacted. We did not find a significant effect of baseline expectations, belief of group assignment, or individual characteristics on measures of WM and verbal fluency. However, controlling for baseline expectations revealed greater post-intervention improvement on the executive function measures in participants who received high (compared to low) expectation priming. People randomly assigned to receive high expectation priming reported having a more pleasant experience overall, including greater satisfaction. Our findings suggest that expectations of outcomes should be taken into account in tDCS-based experimental studies and clinical trials.

Auditory Event-related Potentials in Mild Cognitive Impairment and Alzheimer's Disease.

BACKGROUND: Mild cognitive deficits are more likely to occur with increasing age, and become more pronounced for people diagnosed with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Conventional methods to identify cognitive declines (i.e., neuropsychological testing and clinical judgment) can lead to false positive diagnoses of cognitive impairment. Tools such as electroencephalography (EEG) offer additional measures of cognitive processing, indexing the electrophysiological changes associated with aging, MCI and AD. OBJECTIVE: We reviewed the literature on EEG to determine if auditory event-related potentials (ERPs) could distinguish between healthy aging, MCI, and AD. METHOD: We searched two electronic databases (Medline and PyscInfo) for articles published between January 2005 and April 2017. Articles were considered for review if they included: i) participants 60 years of age or older; ii) healthy older adults or those diagnosed with MCI or AD; iii) at least one auditory elicited ERP component. RESULTS: Our search revealed 1532 articles (800 after removing duplicates); 719 were excluded through title/abstract review, and of the 81 remaining articles, 30 satisfied inclusion criteria. All studies compared cognitive function between at least two of the three selected populations. Our findings suggest that the P300 and N200 components may distinguish between healthy cognitive aging, MCI, and AD. CONCLUSION: ERPs may be sensitive to progressive cognitive changes due to MCI and AD. The P300 and N200 may help identify patients who are likely to progress from MCI to AD, and could be a valuable clinical tool.

What Do People Expect of Cognitive Enhancement?

Enhancing cognitive function through mentally challenging exercises ("brain training") or non-invasive brain stimulation (NIBS) is an enticing yet controversial prospect. Although use of these methods is increasing rapidly, their effectiveness remains questionable. Notably, cognitive enhancement studies have typically failed to consider participants' expectations. However, high expectations could easily make brain-training approaches appear more effective than they actually are. We addressed this major gap in the literature by assessing the perceived effectiveness of brain training and NIBS in a series of surveys. Our results suggest that people are optimistic about the possibilities of cognitive enhancement, particularly through brain training. Moreover, reading a brief message implying high or low effectiveness of such methods can raise or lower expectations, respectively, suggesting that perceptions of brain training are malleable - at least in the short term. Measuring expectations in brain training and NIBS is important to determining whether these cognitive enhancement methods truly are effective.

Examining the Interactions Between Expectations and tDCS Effects on Motor and Cognitive Performance.

Background: Despite a growing literature and commercial market, the effectiveness of transcranial direct current stimulation (tDCS) remains questionable. Notably, studies rarely examine factors such as expectations of outcomes, which may influence tDCS response through placebo-like effects. Here we sought to determine whether expectations could influence the behavioral outcomes of a tDCS intervention. Methods: Through an initial study and self-replication, we recruited 121 naïve young adults 18-34 years of age (M = 21.14, SD = 3.58; 88 women). We evaluated expectations of tDCS and of motor and cognitive performance at three times: (i) at baseline; (ii) after being primed to have High or Low expectations of outcomes; and (iii) after a single session of sham-controlled anodal tDCS over the left or right motor cortex. Before and after stimulation, participants performed the Grooved Pegboard Test and a choice reaction time task as measures of motor dexterity, response time, and response inhibition. Results: Repeated measures ANOVA revealed that participants had varying, largely uncertain, expectations regarding tDCS effectiveness at baseline. Expectation ratings significantly increased or decreased in response to High or Low priming, respectively, and decreased following the intervention. Response times and accuracy on motor and cognitive measures were largely unaffected by expectation or stimulation conditions. Overall, our analysis revealed no effect attributable to baseline expectations, belief of group assignment, or experimental condition on behavioral outcomes. Subjective experience did not differ based on expectation or stimulation condition. Conclusions: Our results suggest no clear effects of tDCS or of expectations on our performance measures, highlighting the need for further investigations of such stimulation methods.

Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory.

Do you believe in brain training? A questionnaire about expectations of computerised cognitive training.

"Brain training" (i.e., enhancing, rehabilitating, or simply maintaining cognitive function through deliberate cognitive exercise) is growing rapidly in popularity, yet remains highly controversial. Among the greatest problems in current research is the lack of a measure of participants' expectations, which can influence the degree to which they improve over training (i.e., the placebo effect). Here we created a questionnaire to measure the perceived effectiveness of brain-training software. Given the growth in advertising of these programmes, we sought to determine whether even a brief positive (or negative) message about brain training would increase (or decrease) the reported optimism of participants. We measured participants' expectations at baseline, and then following exposure to separate, brief messages that such programmes have either high or low effectiveness. Based on the knowledge they have gleaned from advertising and other real-world sources, people are relatively optimistic about brain training. However, brief messages can influence reported expectations about brain-training results: Reading a brief positive message can increase reported optimism, whereas reading a brief negative message can decrease it. Older adults appear more optimistic about brain training than young adults, especially when they report being knowledgeable about brain training and computers. These data indicate that perceptions of brain training are malleable to at least some extent, and may vary depending on age and other factors. Our questionnaire can serve as a simple, easily-incorporated tool to assess the face validity of brain training interventions and to create a covariate to account for expectations in statistical analyses.

Training the brain: fact and fad in cognitive and behavioral remediation.

Putatively safe and effective for improving cognitive performance in both health and disease, products purported to train the brain appeal to consumers and healthcare practitioners. In an increasingly health-centered society, these applications constitute a burgeoning commercial market. Sparse evidence coupled with lack of scientific rigor, however, leaves claims concerning the impact and duration of such brain training largely unsubstantiated. On the other hand, at least some scientific findings seem to support the effectiveness and sustainability of training for higher brain functions such as attention and working memory. In the present paper we provide a tectonic integration and synthesis of cognitive training approaches. Specifically, we sketch the relative merits and shortcomings of these programs, which often appeal to parents who must choose between side-effect-laden medication and other less conventional options. Here we examine how neuroplasticity allows the healthy as well the impaired to benefit from cognitive training programs. We evaluate the evidence and consider whether brain training can be a stand-alone treatment or an adjunct to pharmacotherapy, outline promising future prospects, and highlight what training outcomes are plausible in line with available data. Future research would determine whether the field of brain training realizes its potential to revolutionize education and rehabilitation or withers away engulfed in controversy.