Clinical Research Directory

L-serine and Strength Training in the Elderly

This study investigates whether taking the amino acid L-serine, either alone or in combination with targeted strength training, can have a positive effect on mental performance, brain function, and physical fitness in older people. Healthy, independent women and men aged 65 to 85 are eligible to participate. Participants will be randomly assigned to one of three groups: placebo, L-serine, or L-serine combined with strength training. Cognitive tests, physical performance tests, and blood and brain tests will be conducted over a period of 48 weeks. The aim is to gain a better understanding of how nutrition and exercise can contribute to healthy aging.

EEG-Guided Binaural Beat Audio to Reduce Performance-Related Stress and Improve Cognition

Performance-related stress can impair sustained attention, inhibitory control, and memory. This randomized, double-blinded, sham-controlled parallel-arm trial evaluates whether a 30-minute EEG-guided binaural beat audio intervention reduces subjective stress/performance anxiety and improves cognition, and whether it changes task-related brain reactivity measured by fMRI. The intervention uses real-time single-electrode EEG recorded over the left prefrontal cortex to dynamically adjust binaural beat frequencies to guide the brain toward a target state; the sham condition uses non-binaural music delivered through identical headphones. Adult music majors preparing for an upcoming concert will complete pre- and post-intervention fMRI sessions during cognitive/music tasks (Stop Signal Reaction Task, Music Reading Task, Music Memory Retrieval Task) and complete visual analog scales (VAS) assessing performance anxiety, stress, and related subjective states. The primary outcomes include fMRI task-related activity in stress-regulation regions (dlPFC, amygdala, hippocampus), behavioral inhibition indices from the stop-signal task, music memory retrieval accuracy, and VAS-reported stress/performance anxiety.

Long-Term Effects of Walnut Consumption on Brain Function

Rationale: Healthy foods, including mixed nuts, may improve brain function, which is essential for cognitive and metabolic health, and may contribute to improved food intake regulation. It is therefore important to investigate the specific effects of walnuts on cerebral blood flow responses before and after intranasal insulin administration, as well as their associated functional benefits. The investigators hypothesize that long-term walnut consumption improves vascular function and insulin-sensitivity in the brain, thereby enhancing cognitive performance and appetite control in abdominally obese men and women. Objective: The primary objectives are to investigate in abdominally obese adults the effects of 24-week walnut consumption on (regional) vascular function and insulin-sensitivity in the brain, while the investigators will also assess changes in cognitive performance and appetite-related brain reward activity (secondary objectives). Cerebral blood flow responses before (brain vascular function) and after the administration of intranasal insulin spray (brain insulin-sensitivity) will be quantified by the non-invasive gold standard magnetic resonance imaging (MRI)-perfusion method Arterial Spin Labeling (ASL). Study design: This intervention study will have a randomized, controlled parallel design. The total study duration will be 24 weeks. Study population: Fifty-five abdominally obese men and (postmenopausal) women (aged 45-75 years) without a history of cardiovascular diseases or complaints will participate. This study population is expected to have a decreased cerebral blood flow at baseline and are also at increased risk of cognitive impairment, allowing for improvement by the intervention. Intervention: Study participants will receive daily 50 g (about 15% of energy) of raw walnuts (walnut intervention) or no walnuts (control intervention) for 24 weeks. Main study parameters/endpoints: At baseline and after 24 weeks (follow-up), participants will visit the research facilities for assessments. The primary endpoint is the difference in the cerebral blood flow response before and after intranasal insulin administration between the walnut and control intervention. Cognitive performance will be assessed, while the investigators will also focus on appetite-related brain reward activity (secondary outcomes).

Acute Effects of Moderate-Intensity Continuous Exercise Versus HIIT on Cognitive Performance and Psychophysiological Responses in Physically Active Adults

This study aims to compare the immediate effects of two common types of exercise-moderate-intensity continuous exercise and high-intensity interval training (HIIT)-on attention, alertness, and physiological responses in physically active young adults. Attention and mental alertness are essential for learning, academic performance, and daily functioning. Previous research suggests that a single session of exercise can temporarily improve cognitive performance, but it is not clear whether moderate exercise or high-intensity interval exercise is more effective in producing these immediate benefits. In this study, participants will complete two supervised treadmill exercise sessions on separate days: one session of moderate-intensity continuous exercise and one session of high-intensity interval training. The order of the two exercise sessions will be randomized, and there will be a rest period of 48 to 72 hours between sessions. Before and immediately after each exercise session, participants will complete computerized cognitive tests that measure sustained attention and reaction time. Heart rate, oxygen saturation, perceived exertion, mood, and alertness will also be measured to evaluate physiological and psychological responses to exercise. By comparing the effects of these two exercise approaches within the same individuals, this study aims to identify which type of exercise leads to better immediate cognitive performance and favorable physiological responses. The findings may help guide exercise recommendations for improving attention, alertness, and overall mental performance in young adults.

High-Dairy Food Patterns and Gut-Brain Axis

Disturbances in brain insulin sensitivity are associated not only with obesity and type 2 diabetes, but also with brain aging and cognitive decline. Longitudinal studies suggest that dietary patterns, particularly those high in dairy intake, may impact brain function via the gut-brain axis. Indeed, dairy foods are known to modulate gut microbiota and may, through this pathway, not only improve brain insulin sensitivity and cognitive performance, but also mental health and appetite regulation. However, underlying mechanisms remain largely unexplored. The primary objective of this study is to evaluate, in older adults with overweight or obesity, the effects of a high-dairy food pattern (4-5 daily servings of (butter)milk, cheese, yogurt, or cottage cheese) compared to a low-dairy food pattern (≤1 serving daily) on (regional) brain vascular function and insulin sensitivity. These outcomes will be quantified using the non-invasive MRI perfusion technique Arterial Spin Labeling (ASL), which assesses cerebral blood flow (CBF) in response to intranasal insulin, a validated physiological marker of brain insulin sensitivity. Secondary objectives include changes in cognitive performance (via the CANTAB neuropsychological test battery), gut microbiota composition (via shotgun metagenomic analysis of fecal samples), and appetite-related brain reward activity (via BOLD-fMRI with food cues). Exploratory analyses include conventional cardiometabolic risk markers (blood pressure, lipid and glucose metabolism), and perceivable (consumer) benefits.

Effects of Long-Duration Spaceflight on General and Spatial Cognition and Its Neural Basis

This study investigates the effects of extended-duration spaceflight (12-month International Space Station missions) on general cognitive performance (measured with the Cognition test battery), spatial cognition, structural and functional brain changes in general, and hippocampal plasticity more specifically relative to the shorter 6-month and 2-month missions.

Lutein, Zeaxathin, and Fish Oil Supplementation

The goal of this clinical trial is to learn the impact of lutein, zeaxanthin, and fish oil (LZF) supplementation in healthy adults. The main question it aims to answer is: Will supplementation with LZF improve macular pigment optical density (MPOD), cognitive performance and bone mass compared to controls after six months? Subjects with an MPOD \<.43 will significantly improve MPOD after 6-months of LZF supplementation. Consuming a LZFO supplement for 6-months will improve visual cognitive performance. Consuming a LZFO supplement for 6-months will improve bone density. Participants will be asked to take either a LZF supplement or placebo daily for 6 months.

Exploring the Cognitive Benefits of a Blackcurrant-Based Supplement in Normobaric Hypoxia

This study investigates the cognitive effects of Ārepa, a blackcurrant-based drink, under simulated high-altitude conditions (4,500m normobaric hypoxia for \~180 minutes). Using a double-blind, randomised, placebo-controlled crossover design, participants will consume either the nootropic blackcurrant-based drink or a taste-matched placebo. Cognitive testing (\~80 minutes) includes Trail-making, Stroop, N-back, Serial 7s/3s, and RVIP tasks. Physiological measures (heart rate, SpO₂, blood) and biomarkers (MAO-B, BDNF, hsCRP, S100B, Prolactin, C3G, Sarmentosin) will be assessed. Scales will evaluate mood, wellbeing, and perceived effects. The aim is to determine if the nootropic drink can support cognitive function in hypoxic environments.

The Effects of Nature-Based Activity vs. Indoor Exercise on Cognition, Psychological, and Physiological Health

This randomized controlled trial aims to investigate the comparative effects of nature-based versus indoor exercise interventions on cognitive performance, psychological well-being, and physiological stress in Malaysian adults. Participants will be randomly assigned to one of four groups: (1) active nature engagement (walking outdoors), (2) passive nature engagement (seated outdoor observation), (3) indoor treadmill walking, or (4) a no-intervention control group. The study will examine changes in attention, working memory, affect, blood pressure, body composition, and salivary cortisol across baseline, mid-point, and post-intervention assessments.

Cognitive-Based Balance Exercises on the Shooting Performance of Archers

The aim of this treatment study is to determine the effects of cognitive-based balance exercises on archers' shooting performance. The study focuses on archers and examines the effects of cognitive-based dynamic and static balance exercises on shooting accuracy. In this context, the main questions that the study aims to answer are as follows: * Cognitive-based balance exercises applied to archers have no effect on shooting performance. * Cognitive-based balance exercises applied to archers have an effect on shooting performance. The researchers will evaluate the effects of the interventions on shooting performance by comparing the performance differences between archers who apply cognitive-based balance exercises and archers who only do balance exercises. Participants: * The control group will apply various balance exercises during the 12-week training period. The study group will apply cognitive-based balance exercises. * They will be subjected to performance tests that evaluate static balance, dynamic balance and shooting accuracy.

Use Muscadine Wine Nutraceuticals to Improve Brain Health, Cognition, and Mental Health

Previous studies have shown that polyphenol-rich foods can positively affect cognitive functions, memory, and mood in humans. We hypothesize that both acute and chronic intake of muscadine wine polyphenols will improve cognitive performance and mood through regulating the HPA axis, alleviating inflammation and oxidative stress, and/or inhibiting monoamine oxidase activities

Peanut Consumption on Cognitive, Weight, and Inflammation

A multi-school, two-arm parallel cluster-randomized controlled trial will be conducted in 200 healthy young adolescents from Barcelona (Spain) to evaluate the effect of peanut consumption on cognitive performance, weight management and inflammation. Schools willing to participate will be randomly assigned to either the intervention or the control group. After the recruitment, the participants will follow a peanut-free diet for two weeks. Both arms will receive a multidimensional educational intervention designed by the Gasol Foundation to promote healthy dietary habits based on Mediterranean diet recommendations, along with exercise performance, healthy sleeping habits and emotional knowledge. Half of the participants (intervention group) will consume 25 g of whole skin roasted peanuts as a daily snack to be incorporated into their diet for six months.

Determining Which Regions of the Brain Are Active During Flight Simulation at Separate Timepoints During Training

The overall objective is to identify the cognitive circuits associated with military aviator performance by analyzing what anatomic regions of the brain are functionally "active" (neuronal circuit) while being performing virtual flight simulations, the Precision Instrument Control Task (PICT). The flight simulation test will be conducted at two separate timepoints while the subject is receiving a Functional Magnetic Resonance Imaging (fMRI) scan to evaluate which anatomic and functional brain function is associated with precise performance. By scanning at multiple time points we aim to quantify changes in functional and anatomic connectivity that occur throughout the course of training.

Post-stroke Cognitive Impairment

Present study aims to track the post-stroke cognitive trajectories and to investigate its inter-individual variability.

Clinical Study to Evaluate the Effects of Two Novel Hydration Beverage Formulas on Rehydration in Healthy Adults

The aim of the clinical trial is to evaluate the efficacy of two novel hydration products on rehydration following exercise.