Optimal Cognitive Performance Research Articles

Plasma Neurofilament Light (NfL) associated with retest learning effects on ambulatory cognitive assessments of processing speed: Results from the Einstein Aging Study (EAS)

AbstractBackgroundMeasurement burst designs, using ambulatory cognitive assessments facilitate the dissociation of retest effects from optimal (“asymptotic”) performance. Dissociating these features via cognitive process modeling may reveal indices of subtle cognitive impairment that signal risk for neurocognitive decline. We investigated cross‐sectional associations between plasma NfL (a biomarker of neurodegeneration), retest improvements, and optimal performance on the Symbol Match task, which assesses processing speed by response time (RT), in a racially/ethnically diverse community‐based EAS Study cohort.MethodAnalyses included 283 EAS participants free of dementia (Mean age = 77.4 years, SD = 4.8, Range = 70‐91; 67% Female; 46% Non‐Hispanic White, 40% Non‐Hispanic Black). Among them, 82 met the Jak/Bondi criteria of mild cognitive impairment (MCI). Participants completed a smartphone cognitive battery, resulting in up to 96 assessment sessions (six times per day for 16 days). Plasma NfL concentration was measured using a Single molecule array assay. A mixed‐effect negative exponential model was used to examine the associations between plasma NfL and indices of subtle cognitive impairment adjusting for covariates including age, gender, education, and race/ethnicity. Retest improvement was measured by the exponential decrease in RT across sessions and optimal performance was measured by asymptotic RT (fastest performance).ResultOn average, the RT of the Symbol Match task was 3.4 seconds (SD = 0.9). Mean plasma NfL level was 23.9 pg/mL (SD = 17.5). Higher plasma NfL levels were associated with a reduced retest improvement rate per session (estimate = ‐0.011, 95% confidence interval (‐0.013, ‐0.008) corresponding to one SD increase in plasma NfL, p<0.001). No significant association between plasma NfL and optimal cognitive performance was found. Stratified analyses showed NfL’s association with retest improvement was larger in non‐Hispanic Whites than in non‐Hispanic Blacks (‐0.009 vs ‐0.002), although formal testing of the interaction between NfL and race was not significant. Results remained very similar excluding participants with MCI.ConclusionHigher plasma NfL was associated with a reduced retest improvement rate on a smartphone processing speed task, highlighting its potential value for identifying subtle cognitive impairment. Longitudinal data from larger samples, a broader array of biomarkers and of ambulatory cognitive tests, are required to fully explore these issues.

5-HT4 Receptor Agonist Effects on Functional Connectivity in the Human Brain: Implications for Procognitive Action

BackgroundCognitive deficits are often comorbid with mood disorders and can cause significant functional impairment even after resolution of the primary mood symptoms. We do not currently have pharmacological treatments that adequately address these deficits. 5-HT4 receptor agonists show promise as potential procognitive agents in animal and early human translational studies. Optimal cognitive performance in humans is directly associated with appropriate functional connectivity between specific resting-state neural networks. However, so far the effect of 5-HT4 receptor agonism on resting-state functional connectivity (rsFC) in the brain in humans is unknown. MethodsWe collected resting-state functional magnetic resonance imaging scans from 50 healthy volunteers, of whom 25 received 6 days × 1 mg prucalopride (a highly selective 5-HT4 receptor agonist) and 25 received placebo in a randomized double-blind design. ResultsNetwork analyses identified that participants in the prucalopride group had enhanced rsFC between the central executive network and the posterior/anterior cingulate cortex. Seed analyses also showed greater rsFC between the left and right rostral anterior cingulate cortex and the left lateral occipital cortex, and reduced rsFC between the hippocampus and other default mode network regions. ConclusionsSimilar to other potentially procognitive medications, low-dose prucalopride in healthy volunteers appeared to enhance rsFC between regions involved in cognitive networks and reduce rsFC within the default mode network. This suggests a mechanism for the behavioral cognitive enhancement previously seen with 5-HT4 receptor agonists in humans and supports the potential for 5-HT4 receptor agonists to be used in clinical psychiatric populations.

Mukbang and Me: Implications on Cognition and Physical Well-Being among Undergraduates

Mukbang has become a global eating trend, especially among youths. Mukbang is mainly prevalent on social media platforms and has become addictive content for many who follow such videos. This study explores the effects of watching mukbang on cognitive functions, health problems and social interaction patterns. The study uses neurofeedback to analyse the brainwaves of selected participants who are university-going youths and have a regular habit of watching Mukbang every day. Two situations were recorded using neurofeedback; the first is only watching Mukbang passively, while the other is where the participant watched Mukbang and ate something simultaneously. A beta and alpha brainwave data were chosen to be analysed. Findings showed that the beta brainwave was recorded the highest in watching mukbang passively while the alpha was the highest during watching and eating mukbang. The result shows that anxiety, excitement, and focus were associated with the highest beta waves, while optimal cognitive performance was related to the activation of the upper alpha wave. The analysis provides a perspective to understand the effect of Mukbang on youths, specifically those currently studying at the tertiary level. The study links how idle interest in Mukbang affects cognitive activities and potentially triggers bingeing, worsening the relationship with food. Future research should examine how Mukbang encourages the diet Mukbangers would be tempted to adopt as daily food intake and how it affects long-term cognitive development among university-going youths.

0122 Sleep Hygiene Education Intervention: Sleep Factors and Cognition in College Students

Abstract Introduction College students often struggle to adjust to the demanding nature of college life, which can translate to decreased overall health and poor sleep. Healthy sleep practices are important for obtaining good sleep quality and quantity, leading to optimal cognitive performance. Interventions, including educational approaches to improve sleep in college students, may lead to better concentration, memory retention, and subsequent academic performance. The focus of the current study was to examine habitual sleep habits in college students, provide a brief educational intervention, and investigate potential changes in sleep and cognition. Methods Participants included 14 undergraduate students (6 men, average age M=20.64 years, SD=2.13) who wore wrist actigraphs to measure their typical sleep habits. After one week, participants completed questionnaires about sleep (Pittsburgh Sleep Quality Index, PSQI), sleepiness (Epworth Sleepiness Scale, ESS), and fatigue (Multidimensional Assessment of Fatigue Scale, MAF). Participants also completed cognitive tests (Stroop, Digit Span, and Simple Reaction Time). Subjects participated in a short lecture about healthy sleep hygiene habits and the importance of sleep and then repeated the one-week observational study. Results Paired sample t-tests revealed a significant increase from baseline average sleep duration (M=5.83 hours) to post-intervention sleep duration (6.64 hours; t(13)=-2.532, p=.013). Sleep efficiency (actigraphy) and quality (PSQI) did not improve significantly. ESS scores decreased significantly (t(13)=3.76, p=.002 (pre M=9.29; post M=5.43) and MAF scores decreased significantly (t(13)=2.19, p=.047 (pre M=20.48; post M=15.60). A difference in reaction times for Stroop incongruent prompts approached significance (p=.083, pre M=979.46; post M=884.70), but no differences were found for errors, Digit Span, or Simple Reaction Times. Conclusion The results of this study suggest that one educational lecture about sleep hygiene may be a start to improving sleep in college students. Even a 48-minute increase resulted in decreased sleepiness and fatigue. However, no improvements were found in sleep quality or efficiency. Although a slight improvement was found in reaction time, no other cognitive benefits were noted. More research should be conducted on how to improve sleep habits in college students beyond an educational approach. Support (If Any) None.

The Effects of Circadian Rhythm in Adolescents on Optimal Performance in Cognitive Tasks

Introduction: The circadian rhythm is a sleep-wake cycle determined by differences in serum melatonin and cortisol levels, and affects cognition and behaviour. Past research suggests that young adults tend to perform better on cognitive tasks during the afternoon and evening, which may be the optimal time of day in this population. This research protocol seeks to determine whether cognitive performance is affected at times assumed to be optimal for both populations (evening) compared with suboptimal times (morning). Methods: Individuals would be recruited and divided into two groups: adolescents 13–17 and younger adults aged ages 18–25, with all participants of the afternoon/evening chronotype. Saliva is collected directly preceding test-taking. Each group completes a standard computerized test of simple math, logical reasoning, and executive function at both their optimal time of day (TOD) (3:00 to 6:00 PM) and at their non-optimal time of day (8:00 to 11:00 AM). Neuroelectric activity is recorded using electroencephalography (EEG). Results: We hypothesize that adolescents and younger adults will be at their optimal performance level (measured by EEG and behavioural measures) between 3 to 6 P.M. rather than from 8 to 11 AM, due to their circadian rhythm. We expect TOD to influence reaction times and accuracy during task completion. A difference will be seen across many neural indices such as event-related potentials (ERPs) and alpha and theta power demonstrating optimal performance in the evening. Discussion: Higher cortisol levels and changes in amplitude and latency of P3, N2Pc, N450, and PD ERP indices and differences in alpha and theta frequencies may be associated with optimal cognitive performance. This is related to faster response time, focus, and overall higher accuracy. Based on the anticipated results, one could alter the timing of task completion to fit different age groups’ peak mental ability. Conclusion: Continuously working at non-optimal times could lead to chronic circadian rhythm disruption, which could result in the deterioration of physical and mental health. Aspects of everyday life, such as student test-taking times, can be improved to benefit both individuals and institutions by catering to an individual’s optimal TOD.

Effect of adaptive opportunity on cognitive performance in warm environments

This study investigates the hypothesis that thermal adaptive opportunities available to building occupants affect their cognitive performance and mental workload. The change rate of cerebral blood flow (Δtotal Hb) was measured by Near Infra-Red Spectroscopy (NIRS) and interpreted as the metric of mental workload in subjects while performing cognitive tasks (n-back tests) with, or without access to thermal adaptive opportunities such as regulable fan-induced air flow and clothing insulation adjustment. Participants underwent three experimental conditions: Condition 22 (operative temperature to = 22 °C without adaptive opportunities), Condition 28 (to = 28 °C without adaptive opportunities), and Condition 28w (to = 28 °C with adaptive opportunities. Under Condition 28w, thermal sensations were neutral, while thermal satisfaction and comfort levels were higher than those reported for Condition 28, and the same as those reported under Condition 22. The subjects' mean skin temperature under Condition 22 was the lowest at 32.1 °C, followed by Condition 28w at 33.6 °C, while the highest, 34.5 °C was recorded in Condition 28. No significant differences were observed in accuracy and reaction time of n-back tests between the three different environmental conditions. Under Condition 28w, mental fatigue levels and the left side Δ total Hb results were lowest out of all three conditions, although the differences failed to reach statistical significance. Availability of adaptive opportunities plays a role in expanding the range of thermal environmental conditions for optimal cognitive task performance in a moderately warm environment (to = 28 °C). This finding cannot be fully explained by the direct effect of adaptive behaviours on human heat balance and associated physiological responses, but the unexplained component may potentially be attributed to the psychological dimension of human adaptive response. These findings and their interpretation within an adaptive comfort framework are consistent with the extended-U hypothesis of cognitive performance.

Time of day, time of sleep, and time on task effects on sleepiness and cognitive performance of bus drivers.

Optimal cognitive performance might prevent vehicle accidents. Identifying time-related circadian and homeostatic parameters having an impact on cognitive performance of drivers may be crucial to optimize drivers' performance. In this prospective study conducted on bus drivers, two drivers alternated driving during a 24-h round trip and were accompanied by an interviewer. Each driver was tested using Karolinska Sleepiness Scale (KSS) and the reversed digit span Wechsler Working Memory test before the start of his shift and then every 6h during a "work/driving" day. Psychomotor Vigilance Task (PVT) was assessed before and after the journey. Linear mixed model was used to explore the factors affecting cognitive performance and sleepiness in univariate and multivariate analysis. Among 35 bus drivers, the effect of time of day on working memories was statistically significant (p = 0.001), with the lowest working memory scores at 04:00 am (± 1). The highest score of subjective sleepiness was also at 04:00 am (± 1). The time on task parameter affected sleepiness significantly (p = 0.024) and sleepiness was significantly associated with decreased working memory. Psychomotor Vigilance Task reaction time mean and the number of minor lapses were significantly increased after the journey, which suggested decreased vigilance. In multivariable analysis, a longer interval between the beginning of working hours and testing time (B (95% CI) = 15.25 (0.49 to 30), p = 0.043) was associated with higher (i.e., slower) PVT reaction time mean. These results suggest that optimizing bus drivers' working schedules may improve drivers' sleepiness and cognitive performance and thus increase road safety.

Effect of Ustukhuddus Alavi, a multi-herbal product, on the cognitive performance of adolescent female students

Ethnopharmacological relevanceUstukhuddus Alavi is a polyherbal formula which is introduced by Persian medicine scholars. It is traditionally used to treat brain disorders and is claimed to do so by preprocessing and cleansing the waste products from the brain. According to Persian medicine, the disposal of brain waste products is necessary for optimal cognitive performance. Aim of the studySustaining optimal cognitive performance is crucial for ideal quality of life and higher academic achievements in high school students. The objective of this study was to determine the effects of this multi-component herbal product on the cognitive performance and salivary cortisol levels of adolescent female students. Materials and methodsThe effect of a 6-week randomly assigned Ustukhuddus Alavi versus placebo administration on cognitive performance was assessed by the paced auditory serial addition test (PASAT) at the baseline and after the 3- and 6-week intake of Ustukhuddus Alavi or placebo and the one-month follow-up in 86 healthy female high school students in grades 10 and 11. Additionally, we measured the levels of salivary cortisol of the students pre- and post-intervention. ResultsSignificant mean difference between the Ustukhuddus Alavi and placebo groups in three of the paced auditory serial addition test (PASAT) subscales, namely mental health (p-value = 0.006), sustained attention (p-value = 0.001) and mental fatigue (p-value = 0.001), were observed after six weeks. We also found a significant difference between the mean salivary cortisol level of the two groups after the intervention (p-value = 0.047). ConclusionsThese findings reveal that the intake of the multi-ingredient herbal product Ustukhuddus Alavi for six weeks can be helpful for cognitive function and cortisol levels in female high school students. These positive effects seem to be related to the increase in sustained attention and the decrease in mental fatigue.

Changes in Sleep Duration and the Risk of Cognitive Impairment Among Older Adults Aged 65 Years and Over — China, 2014–2019

<abstract abstract-type="Summary"> <sec> <b>What is already known about this topic?</b> Earlier studies indicated that shorter or excessive sleep duration at baseline was related to cognitive impairment. Yet few studies have been concerned with the association between sleep duration changes and cognitive performance, especially in low- and middle- income countries. </sec><sec> <b>What is added by this report?</b> A prospective cohort study suggests that maintaining moderate sleep duration may lead to optimal cognitive performance. Either decreasing, increasing, or keeping a longer sleep duration is associated with the risk of cognitive impairment among Chinese elderly aged 65 years and over. </sec><sec> <b>What are the implications for public health practice?</b> Maintaining a moderate sleep duration may be a protective factor against cognitive impairment. Therefore, we need to pay attention to the seniors' sleep health and prevent or delay the progression of cognitive impairment through sleep therapy. </sec>

Improving Psychological Resilience with Cognitive Retraining Methods Using EEG Brain Network Biomarkers: Example from UND/NASA Lunar/Martian Habitat

The brain is the only organ that does not heal itself once injured, but it does adapt and relearn quickly once injured. Whether the brain is cognitively optimized or is dysfunctional, the same brain networks and brain systems are at play to optimize or regulate and repair. That is why studying brain function of optimized brains from astronaut candidates, or individuals within TBI and depression populations can help both ends of the cognitive spectrum to achieve repair for dysfunctional populations or maintain optimal performance. Opportunities to increase coping capabilities neurophysiologically that impact psychological resilience are appealing both clinically and when applied to space travel. The subject of this paper is reporting the results of one such method that is currently being employed in an ongoing UND/NASA Inflatable Lunar Mars Analog Habitat (ILMAH) simulator study. Our Habitat study’s primary goals are many fold: 1) to develop a predictive profile, based on real-time measurable neurophysiological metrics that model cognitive health and resulting task/behavioral health performance; 2) demonstrate the viability of developing a wearable dry sensor device that produces a profile that can be used in extreme environments such as long duration space missions; 3) demonstrate the viability to provide crew countermeasures that mediate negative reduced resilient stress effects on an on-going and as needed basis. Our study method employs the NeuroCoach® Training System that focuses on developing targeted resilient flexible adaptability neural circuit responses through the application of brain training exercises to support psychological resilience. The training program assumption is that if key neural circuits and network systems that support resilient, adaptive behaviors are coupled with proper problem-solving skills, resilient adaptive behaviors emerge. The NeuroCoach® program is based on modern Restorative Cognitive Rehabilitation Training Methods (rCRT). The program provides in-the-moment neural network performance metrics to monitor and adjust the training difficulty level using a Brain Computer Interface. Experimental and clinical results demonstrate the program success at increasing and maintaining optimal cognitive and brain performance quantitatively (by the numbers) and qualitatively (social reintegration). We have found that by studying astronaut crew needs to remain at optimized performance during long duration space travel as well as our studies with various clinical populations with acquired brain dysfunctions presents us with a unique opportunity to compare. They are opposite ends of the spectrum, but both are instructive in what a damaged brain can potentially achieve vs what an optimized brain might suffer during deep space travel.

Circadian Rhythm and Memory Performance: No Time-Of-Day Effect on Face Recognition

The circadian rhythm regulates arousal and activity levels throughout the day and determines hours of optimal cognitive performance. Thus far, circadian fluctuations in face recognition performance received little attention in the research literature. The current experiment investigated the effects of time-of-day optimality on the ability to recognize faces and discriminate between the contexts in which where they were encountered. Morning- and evening-type participants (N = 91) encoded faces in a crime-related and a neutral context, either at their optimal or non-optimal time of day. Contrary to our hypotheses, neither face recognition nor source monitoring performance benefited from testing at optimal time of day. We discuss peculiarities of face processing that could account for the discrepancy of our findings with word recall and recognition literature.

Concurrent white noise and acute hypobaric hypoxia: Effect on aviation cognitive performance

Introduction: Optimal cognitive performance is the essence of effective execution of a flying mission. Effects of two commonly encountered aviation stressors, hypoxia and noise, on performance have been studied. However, studies on effects of concurrent dual effects of both these stressors on key cognitive parameters are sparse; hence, the objective was to examine these effects. Material and Methods: Cognitive performances were assessed among 30 healthy volunteers (28 males and 2 females) sequentially in four different conditions – baseline (without stressors), 85 dB(A) noise, 14,000 ft altitude, and concurrent exposure to 85 dB(A) noise at 14,000 ft altitude. White noise was simulated through software, altitude in the hypobaric chamber and cognitive performance was assessed with tests from Psychology Experiment Building Language (PEBL) test battery. Data were analyzed using descriptive statistics and repeated measures ANOVA. Results: The study revealed statistically significant direct detrimental effect of altitude and noise on implicit reaction time independently as well as concurrently. However, there was insignificant interaction effect between the dual stressors on implicit reaction time. There were no statistically significant effects of dual stressors on implicit correctness, visuospatial working memory, and selective attention. Although statistically not significant, noise enhanced the performance level in the form of increased Corsi block memory span and Corsi block total score. Conclusion: No significant effect of the dual stressors was observed on most of the cognitive parameters. However, implicit reaction time, a measure of pilot’s risk-taking behavior, was found to be significantly affected by the dual stressors. Further research with a larger sample of aircrew population who differ in age, experience, and other potentially influencing factors is recommended.

Cortical thickness mediates the relationship between DRD2 C957T polymorphism and executive function across the adult lifespan.

Dopamine (DA) signaling is critical for optimal cognitive performance. Aging is accompanied by a change in the strength of this signaling, with a loss of striatal and extrastriatal D2 binding potential. The reduction in dopamine modulation with age negatively influences various aspects of cognition. DRD2 C957T (rs6277) impacts DA D2 receptor density and availability, with C homozygotes linked to lower striatal DA availability and reduced executive functioning (EF), but also high extrastriatal binding potential. Here, we investigated in 176 participants aged 20-94years whether: (1) DRD2 C carriers differ from T carriers in cortical thickness or subcortical volume in areas of high concentrations of D2 receptors that receive projections from mesocortical or nigrostriatal dopaminergic pathways; (2) whether the DRD2*COMT relationship has any synergistic effects on cortical thickness; (3) whether the effect of DRD2 on brain structure depends upon age; and (4) whether DRD2-related regional thinning affects executive function performance. We show that DRD2 impacts cortical thickness in the superior parietal lobule, precuneus, and anterior cingulate (marginal after FDR correction), while statistically controlling sex, age, and COMT genotype. Specifically, C homozygotes demonstrated thinner cortices than both heterozygotes and/or T homozygotes in an age-invariant manner. Additionally, DRD2 predicted executive function performance via cortical thickness. The results highlight that genetic influences on dopamine availability impact cognitive performance via the contribution of brain structure in cortical regions influenced by DRD2.

Assessment of sleep health in collegiate athletes using the Athlete Sleep Screening Questionnaire

The objective of this study was to characterize sleep health in a large, diverse population of college athletes. The study utilized the Athletic Sleep Screening Questionnaire, a clinically validated questionnaire, designed to screen athletes for a clinically significant degree of poor sleep health, and to determine if they require intervention. College athletes from 4 different National College Athletic Association institutions were surveyed using the Athletic Sleep Screening Questionnaire. Descriptive information including sex, sport, and college year was also collected. The Athletic Sleep Screening Questionnaire was scored according to prior clinically validated methods to determine a sleep difficulty score, clinical sleep problem category (none, mild, moderate, or severe), and need for assessment by a physician due to poor sleep health. A total of 1055 surveys were collected with a 95% response rate. Respondents were 36% female, 64% male, and included athletes competing in 15 different sports. Approximately 25% of participants were found to have a clinically meaningful problem with their sleep. Athletes entering their second or higher year of college were more likely to report worse sleep compared to those entering their first year (one-way analysis of variance, Kruskall-Wallis P < .001). A substantial portion of college athletes experience poor sleep health and would benefit from interventions aimed at improving sleep. The Athletic Sleep Screening Questionnaire appears to be a cost- and time-efficient way to evaluate sleep health in a large athletic population.

Cognitive Performance During Confinement and Sleep Restriction in NASA's Human Exploration Research Analog (HERA).

Maintaining optimal cognitive performance in astronauts during spaceflight is critical to crewmember safety and mission success. To investigate the combined effects of confinement, isolation, and sleep deprivation on cognitive performance during spaceflight, we administered the computerized neurobehavioral test battery “Cognition” to crew members of simulated spaceflight missions as part of NASA’s ground-based Human Exploration Research Analog project. Cognition was administered to N = 32 astronaut-like subjects in four 1-week missions (campaign 1) and four 2 weeks missions (campaign 2), with four crewmembers per mission. In both campaigns, subjects performed significantly faster on Cognition tasks across time in mission without sacrificing accuracy, which is indicative of a learning effect. On an alertness and affect survey, subjects self-reported significant improvement in several affective domains with time in mission. During the sleep restriction challenge, subjects in campaign 1 were significantly less accurate on a facial emotion identification task during a night of partial sleep restriction. Subjects in campaign 2 were significantly slower and less accurate on psychomotor vigilance, and slower on cognitive throughput and motor praxis tasks during a night of total sleep deprivation. On the survey, subjects reported significantly worsening mood during the sleep loss challenge on several affective domains. These findings suggest that confinement and relative isolation of up to 2 weeks in this environment do not induce a significant negative impact on cognitive performance in any of the domains examined by Cognition, although the concurrent practice effect may have masked some of the mission’s effects. Conversely, a night of total sleep deprivation significantly decreased psychomotor vigilance and cognitive throughput performance in astronaut-like subjects. This underscores the importance of using cognitive tests designed specifically for the astronaut population, and that survey a range of cognitive domains to detect the differential effects of the wide range of stressors common to the spaceflight environment.

No evidence that footedness in pheasants influences cognitive performance in tasks assessing colour discrimination and spatial ability

ABSTRACTThe differential specialization of each side of the brain facilitates the parallel processing of information and has been documented in a wide range of animals. Animals that are more lateralized as indicated by consistent preferential limb use are commonly reported to exhibit superior cognitive ability as well as other behavioural advantages. We assayed the lateralization of 135 young pheasants (Phasianus colchicus), indicated by their footedness in a spontaneous stepping task, and related this measure to individual performance in either 3 assays of visual or spatial learning and memory. We found no evidence that pronounced footedness enhances cognitive ability in any of the tasks. We also found no evidence that an intermediate footedness relates to better cognitive performance. This lack of relationship is surprising because previous work revealed that pheasants have a slight population bias towards right footedness, and when released into the wild, individuals with higher degrees of footedness were more likely to die. One explanation for why extreme lateralization is constrained was that it led to poorer cognitive performance, or that optimal cognitive performance was associated with some intermediate level of lateralization. This stabilizing selection could explain the pattern of moderate lateralization that is seen in most non-human species that have been studied. However, we found no evidence in this study to support this explanation.

T80SCHIZOPHRENIA POLYGENIC RISK SCORE CORRELATES WITH DECREASED COGNITIVE FUNCTIONS IN ULTRA-HIGH-RISK INDIVIDUALS FOR PSYCHOSIS

Proper dopamine (DA) signaling is likely necessary for maintaining optimal cognitive performance as we age, particularly in prefrontal-parietal networks and in fronto-striatal networks. Thus, reduced DA availability is a salient risk factor for accelerated cognitive aging. A common polymorphism that affects DA D1 receptor dopamine availability, COMT Val158Met (rs4680), influences enzymatic breakdown of DA, with COMT Val carriers having a 3- to 4-fold reduction in synaptic DA compared to COMT Met carriers. Furthermore, dopamine receptors and postsynaptic availability are drastically reduced with aging, as is executive function performance that ostensibly relies on these pathways. Here, we investigated in 176 individuals aged 20–94 years whether: (1) COMT Val carriers differ from their Met counterparts in thickness of regional cortices receiving D1 receptor pathways: prefrontal, parietal, cingulate cortices; (2) this gene-brain association differs across the adult lifespan; and (3) COMT-related regional thinning evidences cognitive consequences. We found that COMT Val carriers evidenced thinner cortex in prefrontal, parietal, and posterior cingulate cortices than COMT Met carriers and this effect was not age-dependent. Further, we demonstrate that thickness of these regions significantly mediates the effect of COMT genotype on an executive function composite measure. These results suggest that poorer executive function performance is due partly to thinner association cortex in dopaminergic-rich regions, and particularly so in individuals who are genetically predisposed to lower postsynaptic dopamine availability, regardless of age.

Patients with ADHD are being overmedicated (for optimal cognitive performance)

Patients with ADHD are being overmedicated (for optimal cognitive performance)

A Fusion Feature for Enhancing the Performance of Classification in Working Memory Load With Single-Trial Detection.

In traditional brain-computer interfaces (BCIs), using only a certain type of feature or a simple mixture of different features cannot meet the requirements for high performance in classification. Moreover, a simple mixture of various features might lead to information redundancies and thus increase the computational complexity. In this paper, we studied the feasibility of integrating two kinds of features, which showed opposite variation trends as the memory load levels increase, into a single fusion feature. We also proposed a feature fusion framework based on non-invasive electroencephalography to classify the memory load levels and estimate the workload for a series of challenging working memory (WM) tasks (involving delayed match-to-sample tasks) on a single-trial basis. A novel fusion feature called spectral entropy/Lempel-Ziv complexity (SEn/LZC) was proposed to classify three memory load levels. The results showed that the generalization of the support vector machine (SVM) with SEn/LZC was significantly higher than the generalization of an SVM with four other types of feature, namely SEn, LZC, SEn&LZC and LZC/SEn. The findings suggested that the proposed fusion feature could act as a biomarker to successfully distinguish different load levels and that the constructed framework could achieve consistency between optimal cognitive performance and fusion features. In addition, the proposed fusion framework could provide a new method of successfully promoting the classification generalization of BCI and implicitly evaluating the mental workload.

Chronic short sleep and neurodegeneration

Neuroscience The locus ceruleus is a brain region that is critical for optimal cognitive performance and brain health. Its neurons degenerate during mild cognitive impairment and the early stages of Alzheimer's disease (AD). Zhu et al. investigated the role of chronic sleep deprivation on the protein tau, which is found abundantly in the brain and is associated with AD. In mice, a shortage of sleep in early life advanced the temporal progression of toxic tau accumulation, worsened neurobehavioral impairment, and increased the abundance of soluble tau oligomers within the locus ceruleus and other regions. Lack of sleep promoted neurodegeneration in the locus ceruleus and other tau-affected areas, and the effects persisted for months. Chronic sleep disruption may thus contribute to the progression of AD and related diseases. J. Neurosci. 38 , 10255 (2018).