Healthy Clinical Trials

The core objective of this study is to enhance the translational potential of this electroencephalogram (EEG) biomarker by using ketamine(KET)-induced gamma potentiation as a prognostic marker of 4-week treatment outcome. Previous research focused exclusively on KET-induced gamma band potentiation (GBP) in the context of a single infusion. Our study design captures the clinical variation associated with real-world treatment resistant depression (TRD) patients and allows us to analyze the relative importance of GBP to antidepressant symptom reduction across the induction phase of treatment. If successful, it provides a compelling rationale for a larger prospective investigation of gamma dynamics as a moderator of outcome to varied TRD therapies which impact the balance of cortical excitation and inhibition. Read Less

Chronic low back pain (CLBP) is a pervasive disorder affecting up to one-fifth of adults globally and is the single greatest cause of disability worldwide. Despite the high prevalence and detrimental impact of CLBP, its treatments and mechanisms remain largely unclear. Biomarkers that predict symptom progression in CLBP support precision-based treatments and ultimately aid in reducing suffering. Longitudinal brain-based resting-state neuroimaging of patients with CLBP has revealed neural networks that predict pain chronification and its symptom progression. Although early findings suggest that measurements of brain networks can lead to the development of prognostic biomarkers, the predictive ability of these models is strongest for short-term follow-up. Measurements of different neural systems may provide additional benefits with better predictive power. Emotional and cognitive dysfunction is common in CLBP, occurring at the behavioral and cerebral level, presenting a unique opportunity to detect prognostic brain-based biomarkers. Likewise, improvements in electroencephalogram (EEG) neuroimaging strategies have led to increased spatial resolution, enabling researchers to overcome the limitations of classically used neuroimaging modalities (e.g., magnetic resonance imaging [MRI] and functional MRI), such as high cost and limited accessibility. Using longitudinal EEG, this patient-oriented research project will provide a comprehensive neural picture of emotional, cognitive, and resting-state networks in patients with CLBP, which will aid in predicting symptom progression in CLBP. Through this award, the investigators will use modern EEG source analysis strategies to track biomarkers at baseline and 1- and 2-month follow-ups and their covariance with markers for pain and emotional and cognitive dysfunction. A 5-month follow up will also be used to only assess patient reported outcomes. In Aim 1, the investigators will identify and characterize differences in resting-state, emotional, and cognitive networks between patients with CLPB and age/sex-matched controls. In Aim 2, the investigators will identify within-subject changes across time and their relationship with clinical symptoms. In Aim 3, as an exploratory aim, the investigators will apply machine- and deep-learning strategies to detect a comprehensive signature of CLBP using EEG features from resting-state, emotional, and cognitive networks. Read Less

Injuries affecting the central nervous system may disrupt the cortical pathways to muscles causing loss of motor control. Nevertheless, the brain still exhibits sensorimotor rhythms (SMRs) during movement intents or motor imagery (MI), which is the mental rehearsal of the kinesthetics of a movement without actually performing it. Brain-computer interfaces (BCIs) can decode SMRs to control assistive devices and promote functional recovery. Despite rapid advancements in non-invasive BCI systems based on EEG, two persistent challenges remain: First, the instability of SMR patterns due to the non-stationarity of neural signals, which may significantly degrade BCI performance over days and hamper the effectiveness of BCI-based rehabilitation. Second, differentiating MI patterns corresponding to fine hand movements of the same limb is still difficult due to the low spatial resolution of EEG. To address the first challenge, subjects usually learn to elicit reliable SMR and improve BCI control through longitudinal training, so a fundamental question is how to accelerate subject training building upon the SMR neurophysiology. In this study, the investigators hypothesize that conditioning the brain with transcutaneous electrical spinal stimulation, which reportedly induces cortical inhibition, would constrain the neural dynamics and promote focal and strong SMR modulations in subsequent MI-based BCI training sessions - leading to accelerated BCI training. To address the second challenge, the investigators hypothesize that neuromuscular electrical stimulation (NMES) applied contingent to the voluntary activation of the primary motor cortex through MI can help differentiate patterns of activity associated with different hand movements of the same limb by consistently recruiting the separate neural pathways associated with each of the movements within a closed-loop BCI setup. The investigators study the neuroplastic changes associated with training with the two stimulation modalities. Read Less

The purpose of this research is to compare sympathetic function (flight or fight system) and arterial health including structure and mechanics of participants with history of spontaneous coronary artery dissection (SCAD) to age and sex matched control participants. Read Less

This study is being done to better understand how amino acids alter the release of glucagon and insulin compared to glucose alone in health and disease. Read Less

This study will determine the contribution of glycolate metabolism to urinary oxalate excretion in healthy subjects, using carbon 13 isotope glycolate tracer technique and a low-oxalate controlled diet. Read Less

The goal of this study is to understand what people understand from medical illustrations, and what meaning and emotions (such as anxiety) they derive from different design elements. Read Less

This study plans to learn more about metabolic responses to aerobic exercise at different times of the day (morning or evening) under fasting versus fed conditions. Read Less

This study is a double blind, randomized, placebo-controlled, Phase 1 study in two parts: single ascending doses and food effect (Part 1) and multiple ascending doses (Part 2). Read Less

The goal of this study is to understand the basic brain mechanisms supporting episodic memory in healthy young adults. Transcranial magnetic stimulation will be used to influence brain activity in regions thought to be important for episodic memory. Behavioral testing and MRI will be used to measure the effects of stimulation on memory and on changes in brain network interactions, allowing us to draw causal inferences regarding the role of specific brain regions in memory processes. Read Less

The goal of this controlled feeding trial is to learn about the metabolism of polyphenols, a common class of compounds found in plant-based foods, by the gut microbiome. It will evaluate how differences in gut bacteria across individuals influence metabolism of polyphenols from foods, which may influence health benefits that people receive from different foods. Read Less

Humans are constantly exposed to a variety of light types, created naturally or through artificial means. Light exposure captured by the eyes impacts many physiological functions in humans, including but not limited to cognitive output, fatigue levels, and mood regulation. The level of impact on cognitive learning from different types of light on undergraduate adult students remains unclear. Read Less