Individual Cognition Research Articles

Cooperation with dynamic asymmetric evaluation in complex networks from a risk perspective.

The choice of strategy exposes individuals to the risk of betrayal. This induces individuals' irrational tendencies in strategy selection, which further influences the emergence of cooperative behavior. However, the underlying mechanisms connecting risk perception and the emergence of cooperation are still not fully understood. To address this, the classic evolutionary game model on complex networks is extended. We depict the interaction between strategy imitation and payoff evaluation from two perspectives: dynamic adjustment and irrational assessment. Specifically, the probability distortion involved in the dynamic selection of imitative reference points, as well as the asymmetric psychological utility associated with reference point dependence, is emphasized. Monte Carlo simulations demonstrate that individual irrational cognition induced by the risk of strategy selection can promote the emergence of cooperative behavior. Among them, the risk sensitivity within psychological utility has the most significant moderating effect. Moreover, the promoting effect of strong heterogeneity and high clustering in the network topology on cooperation under risk scenarios has been clarified. Additionally, the influence of initial states on the emergence of cooperation follows a step-like pattern. This research offers valuable insights for further exploring the cooperation mechanisms among irrational agents, even in scenarios involving the regulation of group cooperation behavior in risky situations.

Failure Mode and Effect Analysis (FMEA) Approach Based on Avoidance of Aggregation Discrepancy

As a powerful forward-looking risk management technique, FMEA has been widely used for reliability and security analysis in engineering management fields. In practice, the implementation of FMEA involves the participation of multiple members with distinct knowledge, experience, and cultural background, thus, FMEA is a typical multicriteria group decision-making problem. However, the existence of the aggregation discrepancy issue in FMEA problems with group decision-making leads to collective evaluation conflicts that bring about decision bias for further risk management. This article proposes an AADFMEA method based on multiple-objective optimization to promote the accuracy and reliability of collective assessment information in FMEA members, in which the 10-point qualitative scale is used for evaluation. Additionally, the AADFMEA method responds to the different individual cognitions to a specific evaluation value from multiple members by constraining the risk prioritization to derive more reasonable collective risk evaluation information. Finally, two case studies are presented to show that the AADFMEA method has a good application value, and the simulation analysis was conducted to verify the effectiveness of the proposed AADFMEA approach.

Effect of Training for an Athletic Challenge on Illness Cognition in Individuals with Chronic Disability: A Prospective Cohort Study.

Illness cognitions (IC) influence how a patient adapts to a chronic disease. The aim was (1) to determine if training for a handcycling mountain time trial (HandbikeBattle) improves IC and (2) to identify factors associated with IC change scores. Persons with a chronic disability (N = 220; including N = 151 with spinal cord disorder) trained 5 months and participated in the time trial. The IC Questionnaire measured helplessness, acceptance, perceived benefits and was assessed before training (T1), after training (T2), and four months after the event (T3). Age, sex, body mass index (BMI), time since injury (TSI), disability characteristics, self-efficacy, mental health (MH) and musculoskeletal pain were obtained at T1. Multilevel regression analyses showed that helplessness decreased (from 11.96 to 11.28, p < 0.01) and perceived benefits increased (from 16.91 to 17.58, p < 0.01) from T1 to T2. For helplessness this decrease persisted during follow-up (11.16 at T3). Changes in helplessness were associated with self-efficacy (p = 0.02), MH (p = 0.02) and lesion completeness (p = 0.02), and were independent of disability type (p = 0.66), lesion level (p = 0.30) and demographics such as sex (p = 0.29) and age (p = 0.67). Training with peers may improve helplessness and perceived benefits in individuals with a chronic disability. Especially individuals with MH problems might benefit from training for an athletic challenge with peers to improve illness cognitions, and ultimately, quality of life.

Neuromorphometric associations with mood, cognition, and self-reported exercise levels in epilepsy and healthy individuals

Regular physical activity may promote beneficial neuroplasticity, e.g., increased hippocampus volume. However, it is unclear whether self-reported physical exercise in leisure (PEL) levels are associated with the brain structure features demonstrated by exercise interventions. This pilot study investigated the relationship between PEL, mood, cognition, and neuromorphometry in patients with idiopathic generalized epilepsy (IGEs) compared to healthy controls (HCs). Seventeen IGEs and 19 age- and sex-matched HCs underwent magnetic resonance imaging (MRI) at 3T. The Baecke Questionnaire of Habitual Physical Activity, Profile of Mood States, and Montreal Cognitive Assessment (MoCA) assessed PEL, mood, and cognition, respectively. Structural MRI data were analyzed by voxel- and surface-based morphometry. IGEs had significantly lower PEL (p < 0.001), poorer mood (p = 0.029), and lower MoCA scores (p = 0.027) than HCs. These group differences were associated with reduced volume, decreased gyrification, and altered surface topology (IGEs < HCs) in frontal, temporal and cerebellar regions involved in executive function, memory retrieval, and emotional regulation, respectively.These preliminary results support the notion that increased PEL may promote neuroplasticity in IGEs, thus emphasizing the role of physical activity in promoting brain health in people with epilepsy.

Nonlinguistic Cognitive Functions of Mandarin Speakers With Poststroke Aphasia.

The purpose of this study was to examine the cognitive functions of Mandarin speakers with poststroke aphasia and to investigate the relationship between nonlinguistic cognitive deficits and the severity of aphasia. Twenty-three adults with aphasia resulting from left-hemispheric stroke and 23 adults matched for age and educational level completed a series of six nonlinguistic cognitive tests measuring nonverbal intelligence, short-term memory, visual selective attention, visual alternating attention, auditory selective attention, and auditory alternating attention. A standardized aphasia assessment (Concise Chinese Aphasia Test [CCAT]) was also conducted to evaluate the severity of aphasia. Data analyses examined cognitive functions by comparing task performance of the two groups and examining the relationship between scores on the cognitive tasks and aphasia severity based on a hierarchical regression analysis. The aphasia group scored significantly lower than the control group on all nonlinguistic cognitive tasks with large effect sizes (d = 0.95 ~ 1.54). Significant associations between different nonlinguistic cognitive tasks and CCAT subtests were observed. Results from the hierarchical regression analysis showed that auditory alternating attention was the only factor that significantly predicted aphasia severity based on CCAT overall scores after age and education level were taken into account. The findings align with prior research observing deficits in nonlinguistic cognition in individuals with aphasia. Implications for clinical practice and future research are discussed.

Dysfunctions of multiscale dynamic brain functional networks in subjective cognitive decline.

Subjective cognitive decline is potentially the earliest symptom of Alzheimer's disease, whose objective neurological basis remains elusive. To explore the potential biomarkers for subjective cognitive decline, we developed a novel deep learning method based on multiscale dynamical brain functional networks to identify subjective cognitive declines. We retrospectively constructed an internal data set (with 112 subjective cognitive decline and 64 healthy control subjects) to develop and internally validate the deep learning model. Conventional deep learning methods based on static and dynamic brain functional networks are compared. After the model is established, we prospectively collect an external data set (26 subjective cognitive decline and 12 healthy control subjects) for testing. Meanwhile, our method provides monitoring of the transitions between normal and abnormal (subjective cognitive decline-related) dynamical functional network states. The features of abnormal dynamical functional network states are quantified by network and variability metrics and associated with individual cognitions. Our method achieves an area under the receiver operating characteristic curve of 0.807 ± 0.046 in the internal validation data set and of 0.707 (P = 0.007) in the external testing data set, which shows improvements compared to conventional methods. The method further suggests that, at the local level, the abnormal dynamical functional network states are characterized by decreased connectivity strength and increased connectivity variability at different spatial scales. At the network level, the abnormal states are featured by scale-specifically altered modularity and all-scale decreased efficiency. Low tendencies to stay in abnormal states and high state transition variabilities are significantly associated with high general, language and executive functions. Overall, our work supports the deficits in multiscale brain dynamical functional networks detected by the deep learning method as reliable and meaningful neural alternation underpinning subjective cognitive decline.

Sleep and memory consolidation in healthy, neurotypical children, and adults: a summary of systematic reviews and meta-analyses.

This review systematically assesses the impact of sleep on memory and cognition in healthy individuals across different life stages. It specifically examines how sleep affects memory processes in children, adults, and older adults. The methodology involved a comprehensive literature search, starting with 46 known papers. Keywords and Mesh terms related to sleep and memory consolidation were derived using the Word Frequency Analysis tool in SR Accelerator and Mesh on Demand. A detailed search on PubMed yielded a large set of records. Classifier training on 4854 decisions, these were narrowed down to 1437 papers for full-text screening, culminating in 19 systematic reviews and meta-analyses. Sleep enhances memory consolidation, especially for complex declarative information. While the role of sleep in procedural memory consolidation in children remains less robust compared to declarative memory, findings suggest potential but inconsistent benefits. Sleep improves prospective memory consolidation and aids in complex associative memory tasks. Memory reactivation during sleep, specifically slow-wave sleep, and spindles are implicated in memory consolidation. Meta-analytic evidence suggests that while sleep benefits both emotional and neutral memory consolidation, there is no strong preferential effect of sleep on emotional memory in comparison to neutral memory. In older adults, there is a noticeable reduction in sleep-dependent memory consolidation, particularly for declarative memory, likely linked to a decline in slow-wave sleep. This suggests a decrease in the benefits of sleep for memory consolidation with aging. Overall, the review underscores the importance of sleep in memory processes across all ages, highlighting variations in its impact on different types of memory and across age groups. It points to future research directions for enhancing understanding and practical applications in clinical and educational settings.

Acetylcholine muscarinic M1 receptors in the rodent prefrontal cortex modulate cognitive abilities to establish social hierarchy.

In most social species, the attainment of social dominance is strongly affected by personality traits. Dominant individuals show better cognitive abilities, however, whether an individual's cognition can determine its social status has remained inconclusive. We found that mice show better cognitive abilities tend to possess a higher social rank after cohousing. The dynamic release of acetylcholine (ACh) in the prelimbic cortex (PL) is correlated with mouse dominance behavior. ACh enhanced the excitability of the PL neurons via acetylcholine muscarinic M1 receptors (M1). Inhibition of M1 impaired mice cognitive performance and induced losing in social competition. Mice with M1 deficiency in the PL performed worse on cognitive behavioral tests, and exhibited lower status when re-grouped with others. Elevating ACh level in the PL of subordinate mice induced winning. These results provide direct evidence for the involvement of M1 in social hierarchy and suggest that social rank can be tuned by altering cognition through cholinergic system.

Positive and Negative Sexual Cognitions of Autistic Individuals

Sexual cognitions are an important aspect of sexual well-being for all individuals; however, little is known about the sexual cognitions of autistic individuals. Therefore, our study aimed to explore the diversity, content, and frequencies of positive (PSC) and negative (NSC) sexual cognitions in this population. A total of 332 participants (57.5% women; 42.5% men) between the ages of 21 and 73 (M = 37.72, SD = 11.15) completed an online survey. Our results showed that almost all participants had experienced both positive and negative sexual cognitions. PSC were more diverse and experienced with greater frequency than NSC. In addition, gender (self-identified as being male) and having had relationship experience were associated with greater diversity and frequency of PSC, but not NSC. In terms of content, the most common experienced sexual cognitions for both men and women were intimacy-related. The men experienced 22 of the 56 PSC and 3 of the 56 NSC significantly more frequently than did the women; there were no cognitions that the women experienced more frequently than the men. A comparison to the results of studies of sexual cognitions among neurotypical individuals suggests that autistic individuals experience sexual cognitions in much the same way as their peers. However, sexual cognitions occur slightly less frequently and are somewhat less diverse. Nonetheless, the way in which they are experienced, and the content of the most frequent cognitions (mainly PSC about intimacy) may be indicative of sexual well-being.

Study protocol for “In-vehicle sensors to detect changes in cognition of older drivers”

BackgroundDriving is a complex behavior that may be affected by early changes in the cognition of older individuals. Early changes in driving behavior may include driving more slowly, making fewer and shorter trips, and errors related to inadequate anticipation of situations. Sensor systems installed in older drivers’ vehicles may detect these changes and may generate early warnings of possible changes in cognition.MethodA naturalistic longitudinal design is employed to obtain continuous information on driving behavior that will be compared with the results of extensive cognitive testing conducted every 3 months for 3 years. A driver facing camera, forward facing camera, and telematics unit are installed in the vehicle and data downloaded every 3 months when the cognitive tests are administered.ResultsData processing and analysis will proceed through a series of steps including data normalization, adding information on external factors (weather, traffic conditions), and identifying critical features (variables). Traditional prediction modeling results will be compared with Recurring Neural Network (RNN) approach to produce Driver Behavior Indices (DBIs), and algorithms to classify drivers within age, gender, ethnic group membership, and other potential group characteristics.ConclusionIt is well established that individuals with progressive dementias are eventually unable to drive safely, yet many remain unaware of their cognitive decrements. Current screening and evaluation services can test only a small number of individuals with cognitive concerns, missing many who need to know if they require treatment. Given the increasing number of sensors being installed in passenger vehicles and pick-up trucks and their increasing acceptability, reconfigured in-vehicle sensing systems could provide widespread, low-cost early warnings of cognitive decline to the large number of older drivers on the road in the U.S. The proposed testing and evaluation of a readily and rapidly available, unobtrusive in-vehicle sensing system could provide the first step toward future widespread, low-cost early warnings of cognitive change for this large number of older drivers in the U.S. and elsewhere.

Translation and Cross-Cultural Adaptation of Nepali Version of the Montreal Cognitive Assessment.

Montreal Cognitive Assessment is widely used in stroke to detect cognitive impairment. The superiority of it over other outcome measures has been well established. It has been cross-culturally translated and has shown excellent psychometric properties. To assess the intervention effect on cognition of Nepalese individuals with stroke using the Montreal Cognitive Assessment, an adapted Nepali version is required as the Nepalese cultural context and language are completely different than the original was developed. Thus, the objective of this study is to translate and cross-culturally adapt Montreal Cognitive Assessment in the Nepali language and see its test-retest reliability and internal consistency. After translating and cross-culturally adapting the Montreal Cognitive Assessment into Nepali using Beaton guidelines. Its Nepali version was administered to 28 individuals with stroke twice keeping the interval of two weeks. Test-retest reliability and internal consistency were assessed using the Intraclass correlation coefficient and Cronbach's alpha. The Montreal Cognitive Assessment was translated into Nepali with significant cultural adaptations and the Nepali version demonstrated excellent psychometric properties as hypothesized. The test-retest reliability and internal Consistency were excellent. The Intraclass correlation coefficient of the total score was 0.990 and Cronbach's alpha value was 0.994 for total scores. The Nepali version of Montreal Cognitive Assessment is reliable to use as a diagnostictool for detecting cognitive impairment in patients with stroke. It is comprehensive, easy to administer and culturally appropriate.

The Effect of Surgical Weight Loss on Cognition in Individuals with Class II/III Obesity

To BackgroundObesity is a global epidemic and is associated with cognitive impairment and dementia. It remains unknown whether weight loss interventions, such as bariatric surgery, can mitigate cognitive impairment. ObjectivesWe aimed to determine the effect of surgical weight loss on cognition in individuals with class II/III obesity. DesignWe performed a prospective cohort study of participants who underwent bariatric surgery. At baseline and two years following surgery, participants completed metabolic risk factor and neuropsychological assessments. SettingParticipants were enrolled from an academic suburban bariatric surgery clinic. ParticipantsThere were 113 participants who completed baseline assessments and 87 completed two-year follow-up assessments (66 in-person and 21 virtual) after bariatric surgery. The mean (SD) age was 46.8 (12.5) years and 64 (73.6%) were female. InterventionBariatric surgery. There were 77 (88.5%) participants that underwent sleeve gastrectomy and 10 (11.5%) that underwent gastric bypass surgery. MeasurementsCognition was assessed using the NIH toolbox cognitive battery (NIHTB-CB) and the Rey Auditory Verbal Learning Test (AVLT). The primary outcome was the change in NIHTB-CB fluid composite score before and after surgery. ResultsThe primary outcome, NIHTB-CB composite score, was stable following bariatric surgery (−0.4 (13.9), p=0.81,n=66). Among secondary outcomes, the NIHTB-CB dimensional card sorting test (executive function assessment), improved (+6.5 (19.9), p=0.01, n=66) while the Rey AVLT delayed recall test (memory assessment) declined (−0.24 (0.83), p=0.01, n=87) following surgery. Improvements to metabolic risk factors and diabetes complications were not associated with improvements to NIHTB-CB composite score. The other 4 NIHTB-CB subtests and Rey AVLT assessments of auditory learning and recognition were stable at follow-up. ConclusionsFollowing bariatric surgery, the age-adjusted composite cognitive outcome did not change, but an executive subtest score improved. These results suggest that bariatric surgery may mitigate the natural history of cognitive decline in individuals with obesity, which is expected to be faster than normal aging, but confirmatory randomized controlled trials are needed. The decline in delayed recall also warrants further studies to determine potential differential effects on cognitive subtests.

Multivariate white matter differences links to cognition in individuals with family history of Alzheimer’s disease and APOE4 genetic risk

AbstractBackgroundGrowing evidence suggests Alzheimer’s disease (AD) develops from a complex cascade of events that vary between individuals. Multivariate approaches have the potential to capture the complexity and heterogeneity of pathologies underlying AD in a more holistic manner compared to univariate approaches.MethodThe MRI data of 105 older adults with a family history of AD from the PREVENT‐AD dataset were analysed. Forty six of these individuals had the APOE4‐3 genotype (greater risk of developing AD), while 59 subjects had the APOE3‐3 genotype (normal risk). Diffusion‐weighted imaging and multi‐echo magnetization transfer, proton density and T1‐weighted data were used to compute several WM metrics (Fig1 b‐c). We computed the voxel‐wise Mahalanobis distance (D2) in WM between APOE4‐3 individuals and a reference group (APOE3‐3) (Fig1). D2 is a multivariate measure that combines several MRI metrics, accounting for their covariance, and yielding a score indicative of the degree of abnormality at each WM voxel (Fig2). Associations between WM D2 and cognitive performance were then investigated (Fig3). Independent component analysis (ICA) was performed on spatial dimensions and linear regression analyses were conducted between D2 in ICA components and scores on items of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). We then extracted the contribution of each MRI feature to D2 in the regions where significant associations were found.ResultA significant negative association (R = ‐0.36, p = 0.014) was found between D2 in a component corresponding to the splenium of the corpus callosum (CC) and scores on RBANS‐immediate memory (Fig3), indicating a link between a greater degree of WM abnormality and poorer performance. Proton density (MPM_PD) and longitudinal relaxation rate (MPM_R1), potentially indicative of WM loss, contributed most to D2 in this region.ConclusionOur findings suggest that microstructural alterations in the posterior part of the CC may play a role in memory deficit in older adults who are at greater risk of developing AD. This is in line with other studies that showed a link between CC degeneration and memory impairments in early AD stages.1 1. Qiu et al. (2016). Inter‐hemispheric dysconnectivity in AD and aMCI. Sci.Rep.

Cerebral perfusion and amyloidosis in the oldest‐old

AbstractBackgroundCerebrovascular contributions to cognitive aging and Alzheimer’s disease (AD) risk represent a growing field in aging research. Studies in the young‐old have demonstrated the critical role of vascular dysregulation (i.e., altered cerebral blood flow) in relation to cognitive decline prior to the appearance of amyloid/tau biomarkers. However, cerebral perfusion has not been well‐studied in the oldest‐old (ages 90 and over), a rapidly growing population that may provide unique insight into resilience and protective factors against dementia in later life. We characterized amyloid and cerebral perfusion profiles of cognitively normal (CN) and cognitively impaired without dementia (CIND) oldest‐old individuals.MethodParticipants were 97 dementia‐free older adults (70 CN and 27 CIND) from the 90+ Study who had available neuroimaging (T1‐MRI, ASL‐MRI, Florbetapir‐PET), demographic, and clinical data. We examined differences between CN and CIND in regional perfusion in areas associated with AD risk (medial temporal lobe, posterior cingulate, precuneus, frontal cortex, inferior parietal lobe) and in amyloid burden using linear regression models controlling for age, sex, education, APOE4 status, and vascular risk factors.ResultCN and CIND groups did not differ in the characteristics compared (Table 1). CIND participants had lower CBF in the posterior cingulate/precuneus than the CN group, but groups did not differ in posterior cingulate/precuneus amyloid SUVR (Figure 1). Additionally, CIND had lower CBF than CN in the inferior parietal lobe but higher CBF in the medial temporal lobe and orbitofrontal cortex (Figure 2).ConclusionCIND individuals had lower regional perfusion in the posterior cingulate/precuneus, but groups did not differ in amyloidosis, highlighting the relationship between cerebrovascular function and cognitive status in the oldest‐old independent of amyloidosis. Our findings complement previously reported posterior cingulate/precuneus hypoperfusion in younger‐old individuals with cognitive impairment and AD. Interestingly, we observed greater medial temporal/frontal perfusion in CIND than CN, similar to previous studies demonstrating initial hyperperfusion preceding hypoperfusion across the CN‐CIND‐Dementia spectrum. This may represent a compensatory vascular mechanism supporting cognition in individuals at greater risk of developing dementia. Future studies will further characterize this cohort with longitudinal perfusion analyses, neuropsychological correlates, and relationships between perfusion and other indices of cerebrovascular dysfunction.

Cognitive and Functional Connectivity Outcomes from a Phase I Trial of Accelerated High‐Dose Repetitive Transcranial Magnetic Stimulation in Amnestic MCI

AbstractBackgroundRepetitive transcranial magnetic stimulation (rTMS), most widely used to treat depression, may have secondary benefits for cognition. Accelerated high‐dose protocols such as intermittent theta burst (iTBS)‐rTMS shorten the treatment course by &gt;50%, potentially improving the feasibility of use in patients with cognitive impairments. Here, we present the results of a phase I trial of iTBS‐rTMS for improving cognition in individuals with amnestic mild cognitive impairment (aMCI) and we explore whether functional brain changes relate to improved cognition.MethodTwenty‐two patients with clinically diagnosed aMCI received 24 sessions of open‐label iTBS‐rTMS to left dorsolateral prefrontal cortex (l‐dlPFC) over 3 days. Nineteen had complete brain MRI and cognitive testing pre‐ and immediately post‐treatment. The primary cognitive outcome was the norm‐adjusted fluid cognition composite T‐score from the NIH Toolbox Cognition Battery. Resting‐state functional connectivity was computed from subject‐specific parcellations mapped to each individual’s functional topology. We examined changes in connectivity within and between the FPN (of with the l‐dlPFC is a hub) and networks implicated in cognition (FPN, dorsal and ventral attention, limbic, default mode). We assessed whether connectivity changes (post minus pre) related to change in fluid cognition.ResultWe achieved a high retention rate of 95%. Treatment with iTBS‐rTMS was safe, with no adverse neuroradiological, neuropsychiatric, or neurocognitive effects. Side effects were minimal and acceptability ratings were high. Treatment produced significant, large effect size (d = 0.98) improvements in fluid cognition (Fig. 1A), and we observed preliminary evidence of related changes in functional connectivity. Specifically, there was a numerical increase in within‐FPN connectivity and a marginally significant increase in connectivity between cognitive networks (Fig. 1B). Further, there was a medium‐strength and marginally significant association between increased within‐FPN connectivity and improved fluid cognition (Fig. 1C).ConclusionThis phase I trial demonstrated that iTBS‐rTMS is safe, feasible, and acceptable in aMCI. Although not dosed for efficacy, we observed large improvements in fluid cognition and preliminary evidence of increased functional connectivity in expected brain networks that related to improved cognition. These promising results support iTBS‐rTMS as potentially efficacious in improving cognition in aMCI, directly informing larger, planned follow‐up randomized controlled phase II trials.

Sex differences in the associations between the risk for late‐life Alzheimer’s disease, protective lifestyle factors and cognition in mid‐life: The PREVENT Dementia study.

AbstractBackgroundIt is now acknowledged that Alzheimer’s Disease (AD) processes are present decades before the symptoms manifest, but whether lifestyle activities can protect against these early AD processes in mid‐life remains poorly understood. Furthermore, the impact of sex as a biological variable on associations between dementia risk, protective lifestyle activities and cognition is unknown. In this study, we aimed to replicate findings from our two recent studies (Deng et al., 2022; Heneghan et al., 2022) on the contribution of mid‐life modifiable activities to cognition in individuals with dementia risk, in a larger independent cohort (N = 461 vs N = 208 used previously). Second, we investigated associations between biological sex, dementia risk, protective lifestyle activities and cognitive performance.MethodCognitively unimpaired middle‐aged participants (40‐59 years; N = 461) completed cognitive and clinical assessments cross‐sectionally. Risk factors (Apolipoprotein E [APOE] ε4 allele status, family history of dementia, and the Cardiovascular Risk Factors Aging and Dementia score [CAIDE]) were assessed and mid‐life activities were measured with the Lifetime of Experiences Questionnaire.ResultReplicating our key previous findings, we found that episodic and relational memory was (a) significantly negatively associated with the CAIDE risk score (Figure 1a), (b) positively associated with stimulating lifestyle activities (Figure 1b), and (c) that females performed significantly better than males in episodic and relational memory (Figure 2a). The key novel finding of this study was that APOE ε4 genotype modulated the association between sex, lifestyle and cognition. Only for APOE ε4+ females, not APOE ε4‐, higher occupational attainment was associated with better episodic and relational memory (Figure 2c, 2d). Conversely, only for APOE ε4+ males, not APOE ε4‐, higher occupational attainment was associated with worse episodic and relational memory (Figure 2c, 2d).ConclusionThese findings suggest that modifiable lifestyle activities offset cognitive decrements due to inherited AD risk in mid‐life and support the targeting of modifiable lifestyle activities for the prevention of AD. Furthermore, these findings suggest an urgent need for targeted research on female‐specific risk factors, to inform personalised strategies for AD prevention and the promotion of female brain health.

Multivariate white matter differences links to cognition in individuals with family history of Alzheimer’s disease and APOE4 genetic risk

AbstractBackgroundGrowing evidence suggests Alzheimer’s disease (AD) develops from a complex cascade of events that vary between individuals. Multivariate approaches have the potential to capture the complexity and heterogeneity of pathologies underlying AD in a more holistic manner compared to univariate approaches.MethodThe MRI data of 105 older adults with a family history of AD from the PREVENT‐AD dataset were analysed. Forty six of these individuals had the APOE4‐3 genotype (greater risk of developing AD), while 59 subjects had the APOE3‐3 genotype (normal risk). Diffusion‐weighted imaging and multi‐echo magnetization transfer, proton density and T1‐weighted data were used to compute several WM metrics (Fig1 b‐c). We computed the voxel‐wise Mahalanobis distance (D2) in WM between APOE4‐3 individuals and a reference group (APOE3‐3) (Fig1). D2 is a multivariate measure that combines several MRI metrics, accounting for their covariance, and yielding a score indicative of the degree of abnormality at each WM voxel (Fig2). Associations between WM D2 and cognitive performance were then investigated (Fig3). Independent component analysis (ICA) was performed on spatial dimensions and linear regression analyses were conducted between D2 in ICA components and scores on items of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). We then extracted the contribution of each MRI feature to D2 in the regions where significant associations were found.ResultA significant negative association (R = ‐0.36, p = 0.014) was found between D2 in a component corresponding to the splenium of the corpus callosum (CC) and scores on RBANS‐immediate memory (Fig3), indicating a link between a greater degree of WM abnormality and poorer performance. Proton density (MPM_PD) and longitudinal relaxation rate (MPM_R1), potentially indicative of WM loss, contributed most to D2 in this region.ConclusionOur findings suggest that microstructural alterations in the posterior part of the CC may play a role in memory deficit in older adults who are at greater risk of developing AD. This is in line with other studies that showed a link between CC degeneration and memory impairments in early AD stages.1 1. Qiu et al. (2016). Inter‐hemispheric dysconnectivity in AD and aMCI. Sci.Rep.

Plasma p‐tau and brain‐derived total tau biomarkers predict longitudinal changes in Aβ, tau, and cognition across the AD continuum

AbstractBackgroundRecent studies have suggested that plasma p‐tau biomarkers are associated with cross‐sectional brain amyloid(Aβ) rather than tau tangle pathology. However, it is still unclear if plasma tau biomarkers are closely related to changes in AD pathophysiology over time. In this work, we aimed to determine if cross‐sectional measures of plasma tau biomarkers are associated with longitudinal changes in Aβ‐PET, tau‐PET, and cognition across the AD spectrum.MethodWe evaluated 157 individuals(96 cognitively unimpaired(CU) and 61 cognitively impaired (CI)) with available baseline measures of plasma Aβ42/40, p‐tau(at threonine 181, 217+, and 231), N‐terminal tau fragments(NTA, a new brain derived tau marker), and glial fibrillary acidic protein(GFAP) and with longitudinal [18F]AZD4694 Aβ‐PET, [18F]MK6340 tau‐PET and Clinical Dementia Rating sum of boxes(CDR‐SB) score from the TRIAD cohort. We also included 321(118 CU and 203 CI) individuals from the ADNI cohort with baseline plasma p‐tau181 and [18F]florbetapir Aβ‐PET and longitudinal CDR‐SB. Using linear regressions adjusted for age and sex we tested the associations between plasma biomarkers and longitudinal changes in Aβ‐PET, tau‐PET, and CDR‐SB.ResultIn CU, changes in tau‐PET were significantly associated only with plasma p‐tau217+(β = 0.331, p&lt;0.01,Figure1A). Changes in Aβ‐PET were significantly associated with p‐tau181(β = 0.594, p&lt;0.01,Figure2A), p‐tau217+(β = 0.311, p = 0.02) and NTA(β = 0.435, p&lt;0.01), while no plasma biomarker was associated with changes in cognition in CU(Figure3A). In CI, changes in tau‐PET were significantly associated with plasma p‐tau181(β = ‐0.338, p = 0.03,Figure1B) and NTA(β = ‐0.379, p = 0.03), while no plasma biomarker was significantly associated with changes in Aβ‐PET. Changes in cognition were significantly associated with plasma p‐tau181(β = 0.340, p = 0.01, Figure3B), p‐tau217+(β = 0.54, p&lt;0.01), and NTA(β = 0.530, p&lt;0.01). Similarly, in the ADNI cohort, plasma p‐tau181 was associated with longitudinal changes in cognition in CI (β = 0.247, p&lt;0.01,Figure3D).ConclusionWe demonstrate that cross‐sectional measures of plasma p‐tau and NTA biomarkers were associated with longitudinal Aβ deposition and tau accumulation in CU, while in CI they were only associated with tau accumulation. Interestingly, plasma tau biomarkers were also associated with changes in cognition in CI individuals. The fact that abnormal levels of plasma tau biomarkers are associated with longitudinal changes in AD pathophysiology has implications for the use of these markers in clinical trials and practice.

초등학교 수학 교과의 원격수업에서 나타나는 교사의 수학적 주목하기

This study aims to explore the impact of the characteristics of remote learning on the overall mathematics classroom. Adapting Lobato et al.'s (2013) notion of “noticing as a phenomenon distributed across individual cognition, social interactions, material resources, and normed practices (p. 809),” the present study reports on similarities and differences in mathematical noticing of two elementary teachers who conducted remote learning on fractions division and how what each teacher noticed was shaped by other elements of their classroom. Although the two teachers taught the same lesson with similar tasks, there were distinct differences between the two teachers' classrooms. Similar to previous studies reporting on students' mathematical noticing, the differences in teachers' centers of focus emerged as a result of focusing interactions, features of mathematical tasks, and the nature of mathematical activities during remote learning. We concluded the study by suggesting the importance of focusing on teachers’ mathematical noticing, implications for future research, and effective professional development design for remote learning.

LTP is Absent in the CA1 Region of the Hippocampus of Male and Female Rett Syndrome Mouse Models

Rett syndrome (RTT) is a debilitating neurodevelopmental disorder caused by mutations in the X-linked methyl-CpG-binding protein 2 (MeCP2) gene, resulting in severe deficits in learning and memory. Alterations in synaptic plasticity have been reported in RTT, however most electrophysiological studies have been performed in male mice only, despite the fact that RTT is primarily found in females. In addition, most studies have focused on excitation, despite the emerging evidence for the important role of inhibition in learning and memory. Here, we performed an electrophysiological characterization in the CA1 region of the hippocampus in both males and females of RTT mouse models with a focus on neurogliaform (NGF) interneurons, given that they are the most abundant dendrite-targeting interneuron subtype in the hippocampus. We found that theta-burst stimulation (TBS) failed to induce long-term potentiation (LTP) in either pyramidal neurons or NGF interneurons in male or female RTT mice, with no apparent changes in short-term plasticity (STP). This failure to induce LTP was accompanied by excitation/inhibition (E/I) imbalances and altered excitability, in a sex- and cell-type specific manner. Specifically, NGF interneurons of male RTT mice displayed increased intrinsic excitability, a depolarized resting membrane potential, and decreased E/I balance, while in female RTT mice, the resting membrane potential was depolarized. Understanding the role of NGF interneurons in RTT animal models is crucial for developing targeted treatments to improve cognition in individuals with this disorder.