UNASSIGNED: Cognitive decline is a prevalent health problem in older adults, and effective treatments remain to be produced. Serum vitamin D, a commonly used biochemical marker, is widely recognized as an indicator of various diseases. Existing research has not fully elucidated the relationship between vitamin D and cognitive function. The aim of this study is to investigate the real relationship between vitamin D and cognitive function and to identify indicators that have a strong predictive effect on cognitive decline.
UNASSIGNED: At first, we used the dataset of the genome-wide association studies studying vitamin D and cognitive performance to conduct Mendelian randomization analysis. Subsequently, we employed linear regression and smooth curve fitting methods to assess the relationship using the National Health and Nutrition Examination Survey data. Finally, we investigated other predictive features of cognitive performance utilizing a machine learning model.
UNASSIGNED: We found that a 1-unit increase in vitamin D is associated with a 6.51% reduction (P < .001) in the risk of cognitive decline. The correlation between vitamin D and cognitive performance is nonlinear, with the inflection point at 79.9 nmol/L (left: β = 0.043, P < .001; right: β = -0.007, P = .420). In machine learning, the top 5 predictors are vitamin D, weight, height, age, and body mass index.
UNASSIGNED: There is a causal relationship between vitamin D and cognitive performance. 79.9 nmol/L could be the optimal dose for vitamin D supplementation in the elderly. Further consideration of other factors in vitamin D interventions is necessary.

BACKGROUND: In attention-deficit/hyperactivity disorder (ADHD), poor inhibitory control is one of the main characteristics, with oculomotor inhibition impairments being considered a potential biomarker of the disorder. While auditory white noise has demonstrated the ability to enhance working memory in this group, visual white noise is still unexplored and so are the effects of both types of white noise stimulation on oculomotor inhibition.
OBJECTIVE: This crossover study aims to explore the impact of auditory and visual white noise on oculomotor inhibition in children with ADHD and typically developing (TD) children. The study will investigate the impact of different noise levels (25% and 50% visual, 78 dB auditory), and performance will be evaluated both with and without noise stimulation. We hypothesize that exposure to white noise will improve performance in children with ADHD and impair the performance for TD children.
METHODS: Memory-guided saccades and prolonged fixations, known for their sensitivity in detecting oculomotor disinhibition in ADHD, will be used to assess performance. Children diagnosed with ADHD, withdrawing from medication for 24 hours, and TD children without psychiatric disorders were recruited for the study.
RESULTS: Data collection was initiated in October 2023 and ended in February 2024. A total of 97 participants were enrolled, and the first results are expected between September and November 2024.
CONCLUSIONS: This study will examine whether cross-modal sensory stimulation can enhance executive function, specifically eye movement control, in children with ADHD. In addition, the study will explore potential differences between auditory and visual noise effects in both groups. Our goal is to identify implications for understanding how noise can be used to improve cognitive performance.
BACKGROUND: ClinicalTrials.gov NCT06057441; https://clinicaltrials.gov/study/NCT06057441.
UNASSIGNED: DERR1-10.2196/56388.

BACKGROUND: Daytime sleepiness affects work efficiency, occupational safety, and public health. Although previous studies have reported an association between environmental carbon dioxide (eCO2) and daytime sleepiness, it has been challenging to draw a firm conclusion due to the lack of standardized sampling and profiling protocols.
OBJECTIVE: We examined the effect of pure CO2 exposure at 5,000 (ppm, parts per million) on daytime sleepiness.
METHODS: Eleven healthy participants (males of 24 ± 3 years, mean ± SD) completed a four-nap multiple sleep latency test (MSLT) protocol in the environmentally controlled chamber under two conditions: the CO2 condition (4,851 ± 229 ppm) and the Control condition (1,102 ± 204 ppm). The subjective sleepiness level and cognitive performances were also evaluated using the Stanford Sleepiness Scale (SSS) questionnaire, Psychomotor Vigilance Test (PVT), and Stroop test after each nap session.
RESULTS: A significant reduction in sleep latency was observed in the CO2 exposure condition (Control vs. CO2 = 13.1 ± 3.3 min vs. 9.7 ± 3.2 min). The subjective sleepiness scores were also significantly higher in the CO2 exposure condition than in the Control condition (Control vs. CO2 = 2.7 ± 0.5 vs. 4.7 ± 0.8). Cognitive responses after naps showed no significant difference across conditions.
CONCLUSIONS: This study revealed that exposure to environmental CO2 at a concentration as high as the upper safety limit at work sites significantly shortened the sleep latency and enhanced subjective sleepiness during naps in the MSLT without affecting cognitive responses after each exposure. Our results demonstrated that exposure to high environmental CO2 induces daytime sleepiness that potentially compromises work efficiency and safety.

BACKGROUND: The gut-brain axis is a bidirectional communication network linking the gastrointestinal tract and the central nervous system via neuronal, hormonal, and antibody signaling pathways. Central to this connection is gut health, encompassing the balance and functionality of gut microbiota, which significantly impacts on mental and cognitive health. This study investigates the association between gut health and cognitive functioning in adults, highlighting the mechanisms by which gut microbiota influence brain health.
OBJECTIVE: To examine the effects of gut health on adult cognitive performance, with a focus on the processes by which gut microbiota impacts brain health.
METHODS: A quantitative cross-sectional study was conducted in Islamabad from January 2024 to April 2024, involving 140 adult participants. Data were collected using a comprehensive 16-item gut health questionnaire and the cognition self-assessment rating scale (C-SARS). The psychometric properties of these scales were assessed, and the data were analyzed using Statistical Product and Service Solutions (SPSS, v26; IBM SPSS Statistics for Windows, Armonk, NY). Analytical and descriptive statistics, including regression, chi-square, independent sample t-tests, and mean and standard deviation, were applied.
RESULTS: The study found moderate associations between gut health and cognitive performance, particularly in memory and processing speed (R² = 0.17, β = -1.9, p = 0.12 for general cognition; R² = 0.01, β = -0.98, p = 0.02 for memory; R² = 0.03, β = -0.18, p = 0.03 for processing speed). Gender and marital status differences were significant, with males exhibiting better gut health scores than females (M = 34.1, SD = 3.2 vs. M = 31.2, SD = 3.2, p = 0.00), and singles showing better cognitive performance compared to married individuals (M = 9.4, SD = 5.4 vs. M = 6.5, SD = 3.7, p = 0.03).
CONCLUSIONS: The study highlights significant associations between gut health and cognitive functions, suggesting that gut microbiota composition can influence cognitive performance. Gender and marital status differences underscore the need to consider individual differences in gut-brain axis research. Future studies should replicate these findings in larger samples and explore gut microbiota-targeted interventions for cognitive health enhancement.

Men and women are characterized by specific physiological, cerebral and emotional characteristics, as well as by the differing nature of their gestures and behaviors. Here, we examined the effects of an observer\'s sex on motor, cognitive and affective behaviors during dart-shooting. We compared men and women\'s kinematic and affective parameters when perfoming alone or when performing in the presence of an observer of a different sex. We found a sex effect on motor and cognitive performance in interaction with participants\' emotional states. We observed improved accuracy and reaction time in men compared to women, which we attributed to (a) differences in emotional sensitivities between the two sexes and (b) men\'s superiority on precision tasks linked to men\'s higher proportion of cerebral white matter. Our findings also suggested a sex difference in the social effect of an observer\'s sex on motor and cognitive performance. Although there was no effect on affective aspects of performance, emotional state seemed to interact strongly with this social effect.

Neurofeedback training is applied in the world of sports as a means to improve athletes\' performance. Training sessions are usually organized on an individual basis, one at a time. Here we investigated if the training could also be organized in groups. Forty-one national-level football (soccer) players (26 females, 15 males) carried out training sessions simultaneously in groups of up to 13, using a wearable device with Bluetooth connection, during their regular training hours at the club. It was possible to obtain good EEG measurements using this setup, albeit with a somewhat higher data loss than usual in standard laboratory sessions. The brain\'s alpha activity was trained using music-based neurofeedback in a crossover design. A training session consisted of alternating periods of neurofeedback and execution of cognitive tasks. EEG alpha (8-12 Hz) activity was higher in the neurofeedback periods compared to the cognitive task periods, and the reverse was true for beta (13-30 Hz) activity. The training program resulted in an increase of 34% in alpha activity associated with the training, and improved the athletes\' performance on task switching and mental rotation tasks. In addition, self-reported sleep duration, as well as scores on the Being in Shape questionnaire (Feeling of Control and Flow) also improved. This study shows that neurofeedback training is feasible in groups of athletes, which can stimulate its application in team sports.

Fibromyalgia, characterized by chronic pain and cognitive impairments, significantly impacts patients\' quality of life. Physical exercise has been shown to improve cognitive functions and reduce pain severity. Additionally, positive affect enhances cognitive flexibility and facilitates better adaptation to chronic pain, suggesting that combining physical activity and positive affect could mitigate cognitive deficits in fibromyalgia patients. Objectives: The objective of this work is to explore the relationship between pain severity and cognitive performance through time spent doing moderate physical activity while taking into account the role of positive affect in fibromyalgia. Methods: This prospective study was structured into two phases of evaluation. First, pain severity, positive affect, and time spent performing moderate physical activity were evaluated, and one week later cognitive performance (assessed through the Stroop test) was also evaluated. The final sample consisted of 231 women with fibromyalgia. Moderated mediation analyses were performed using PROCESS. Results: The moderated mediation model showed that the effect of moderate physical activity on the relationship between pain severity and cognitive performance was significant for low levels of positive affect but not for moderate or high levels. That is, the indirect effect of pain intensity on cognitive performance through time spent doing moderate physical activity only has an effect when patients with fibromyalgia present low levels of positive affect. However, there was no significant indirect effect in the simple mediation model. Conclusions: The findings of this study underscore the importance of considering the level of positive affect when examining the impact of moderate physical activity on cognitive performance in women with fibromyalgia.

Introduction: Neurocognitive and motor impairments are often observed both before and after liver transplantation, resulting in inefficiencies in dual-task performance. Specific aim: The aim of this study was to evaluate the motor-cognitive dual-task performance in liver recipients, with a particular emphasis on cognition, performance status, and the impact of the COVID-19 pandemic. Design: A prospective, cross-sectional, web-based design with a control group was used. The study included 22 liver transplant recipients and 23 controls. Participants completed a motor-cognitive dual-task test (timed up and go test, TUG), a cognitive assessment (mini mental state examination), and a physical performance test (5-repetition sit-to-stand test). The study also used a functional performance status scale (The Karnofsky performance status) and assessed fear of coronavirus disease (fear of COVID-19 scale). Dual-task interference was assessed and the rate of correct responses per second was calculated to assess cognitive performance. Results: The results indicated no statistically significant difference in TUG time and TUG correct responses per second between the groups (group × condition interactions; P > 0.05). There was no significant difference in cognitive and motor dual-task interference during the TUG test between the two groups (P > 0.05). The Karnofsky Performance Status score was significantly correlated with TUG motor dual-task interference (r = -0.424 and P = 0.049). Conclusion: This study suggests that dual-task performance does not differ in cognitive or motor performance between liver recipients and healthy controls under the same dual-task condition. However, further controlled studies are needed to improve the generalizability of these findings.

UNASSIGNED: Overalll, muscular fitness and academic performance are two variables widely studied in the literature. However, evidence on the relationship between muscular fitness and specific school subjects (e.g., physical education), as well as their differences by sex, is scarce.
UNASSIGNED: The aim of this study was to examine the associations between muscular fitness and overall academic performance and between muscular fitness and specific subjects (i.e., language, math, foreign language, and physical education) in a sample of secondary Spanish school students.
UNASSIGNED: For the present study, a sample of 766 students (45% boys, aged 12-17 years). From the Eating Healthy and Daily Life Activities (EHDLA) study was used. The Assessing the Levels of Physical Activity and Fitness (ALPHA-FIT) battery was used to determine handgrip strength and lower body muscular strength. The performance of the different school subjects was provided by the school centers.
UNASSIGNED: Overall, for both boys and girls, higher muscular fitness was associated with greater academic results, with the greatest differences in physical education. However, only significant differences were identified for girls.
UNASSIGNED: Global muscular fitness is important for contributing to cognitive development, both in physical education and in the rest of the subjects of the educational curriculum for adolescents. At the same time, although the association appears to follow the same trend for both sexes, the results seem more evident for girls.

UNASSIGNED: The rise in the aging population highlights the need to address cognitive decline and neurodegenerative diseases. Intermittent hypoxia (IH) protocols show promise in enhancing cognitive abilities and brain health.
UNASSIGNED: This review evaluates IH protocols\' benefits on cognition and brain health in older adults, regardless of cognitive status.
UNASSIGNED: A systematic search following PRISMA guidelines was conducted across four databases (PubMed, Scopus, Web of Science, and Cochrane Library) and two registers, covering records from inception to May 2024 (PROSPERO: CRD42023462177). Inclusion criteria were: 1) original research with quantitative details; 2) studies involving older adults, with or without cognitive impairment; 3) studies including IH protocols; 4) articles analyzing cognition and brain health in older adults.
UNASSIGNED: Seven studies and five registered trials met the criteria. Findings indicate that Intermittent Hypoxia Training (IHT) and Intermittent Hypoxia-Hyperoxia Training (IHHT) improved cognitive functions and brain health. Intermittent Hypoxic Exposure (IHE) improved cerebral tissue oxygen saturation, middle cerebral arterial flow velocity, and cerebral vascular conductance, particularly in cognitively impaired populations. IHT and IHHT had no significant effect on BDNF levels. There is a lack of studies on IHHE in older adults with and without cognitive impairment.
UNASSIGNED: IH protocols may benefit cognition regardless of cognitive status. IHT and IHE positively affect cerebral outcomes, with all protocols having limited effects on BDNF levels. Future research should standardize IH protocols, investigate long-term cognitive effects, and explore neuroprotective biomarkers. Combining these protocols with physical exercise across diverse populations could refine interventions and guide targeted therapeutic strategies.