fMRI Research

This study aims to investigate how different frequencies of transcutaneous Trigeminal Nerve Stimulation (eTNS) affect brain activity and the autonomic nervous system in healthy individuals. Participants will undergo a 3T functional magnetic resonance imaging (fMRI) scan while receiving three different types of nerve stimulation: 2Hz eTNS, 120Hz eTNS, and a sham (inactive) stimulation. The order of these stimulations will be randomly assigned. During the brain scan, researchers will simultaneously monitor the participants' breathing and heart rhythms (using a finger sensor). The main goal is to understand how changing the frequency of eTNS influences the connection between the brain's networks and the body's unconscious physiological responses.

Transcutaneous Trigeminal Nerve Stimulation (eTNS) is a non-invasive technique that modulates brain activity by applying electrical currents to the forehead. However, it remains unclear whether its effects are primarily driven by activating peripheral nerves in the skin (the transcutaneous pathway) or by the electrical current passing directly through the skull into the brain (the transcranial pathway). This study aims to differentiate these two mechanisms in healthy volunteers. Participants will complete two separate MRI scanning sessions. In one session, a local anesthetic (lidocaine) will be applied to numb the skin over the forehead (specifically the supraorbital nerve branch) to temporarily block the peripheral nerve signals. In the other session, no anesthesia will be used. During both sessions, participants will receive active direct current eTNS (DC-eTNS) and a sham (inactive) stimulation while inside a 3T MRI scanner. Researchers will simultaneously measure brain activity (fMRI) and physiological signals (breathing and heart rate). By comparing the brain and bodily responses between the anesthetized and non-anesthetized conditions, the study seeks to determine exactly how eTNS signals travel to and affect the brainstem, cortex, and autonomic nervous system.

The goal of this observational study is to better understand how the brain changes during the treatment of glioma. In particular, the study looks at changes in important brain areas that are responsible for functions such as movement, language, or sensation, as well as the nerve fiber pathways that connect these areas. The main question this study aims to answer is: How do important brain areas and their connections adapt and reorganize over the course of glioma treatment? Patients with glioma will undergo repeated brain imaging examinations as part of their regular medical care. These images will be analyzed over time to observe changes in brain activity and structure during different stages of therapy. By studying these changes, researchers hope to gain new insights into the brain's ability to adapt (neuroplasticity) throughout the entire course of glioma treatment.

Opioid use disorder (OUD) is a chronic relapsing disorder and is well-known for its high-risk rate of overdoses and death. In OUD, sleep and circadian disruptions are highly prevalent, interfere with opioid maintenance treatment outcomes and increase the risk of relapse. So far, commonly used pharmacological sleep treatments fail to improve sleep or decrease illicit drug use in OUD. Thus, there is an urgent need to fill this research gap. Previous work showed that OUD patients who were receiving opioid agonist treatment (MOUD+) exhibited greater irregularity of sleep-wake cycle. In OUD patients, sleep-wake irregularity was associated with years of heroin use and low light exposure. Bright light therapy (BLT) is a very promising circadian/sleep intervention for several sleep, psychiatric and neurological disorders. BLT improved circadian, sleep outcomes and negative mood. In a pilot study, BLT improved objective and subjective sleep in patients with alcohol use disorder. Here investigators proposed an intervention study for MOUD+ patients to determine effects of BLT as an adjunct treatment on sleep and circadian outcomes including endogenous circadian rhythm, rest-activity rhythm and sleep neurophysiology (Primary objectives); and to determine effects of BLT on brain function and on clinical outcomes including negative affect, craving and illicit drug use and whether changes in sleep and circadian rhythm mediate the BLT effect on brain recovery and clinical outcomes (Secondary objectives). Fifty MOUD+ will be assigned either to bright light or to dim light group for 2 weeks. The groups will be matched for age, sex, race and OUD medication (Methadone vs Buprenorphine). The study will run throughout the year such that it occurs during all seasons. Light exposure will be measured with light sensor for additional control. All MOUD+ participants will have a daily 30-min light exposure (bright or dim blue light) in the morning after their habitual wake-up time and will be asked to avoid evening light before bed. Dim light melatonin onset, accelerometer, sleep EEG and questionnaires will be used to measure objective and subjective sleep and circadian outcomes. For brain function, cue-reactivity task will be used to assess brain activation during drug craving. Resting state functional connectivity and brain state dynamics will be assessed by rsfMRI. Mood, opiate craving and illicit drug use will be assessed. All measures will be repeated before and after the treatment. Investigators expect that BLT would normalize sleep and circadian outcomes, attenuate impairments in brain functions and result in better clinical outcomes. If successful, light therapy will provide add-on benefits to opioid agonist therapy and facilitate OUD recovery process.

This clinical trial study aims to detect the imaging characteristics of patients with hepatic encephalopathy (HE) using 7-Tesla (7T) magnetic resonance imaging (MRI).

Objectives and research hypothesis Physical inactivity is a major health concern that has been linked to a variety of chronic diseases, including obesity, diabetes, cancer, cardiovascular diseases, and mental disorders. Recent studies have shown that regular physical activity can decrease the risk of SARS-CoV-2 infection, and severe COVID-19 illnesses, as well as improve antibody response to vaccine. As such, the adoption of a physically active lifestyle carries potential health benefits and has even been referred to as a "miracle cure" by the Academy of Royal Medical Colleges. Despite the implementation of policies that aimed to encourage regular physical activity, the prevalence of insufficient physical activity in high-income countries has increased since 2001 (32% in 2001 vs. 37% in 2018). Given the limited impact of health policies on physical activity engagement, it is essential to explore other avenues of research that can contribute to understanding this high level of inactivity and driving innovative strategies for encouraging physical activity. In this context, the automatic attraction of individuals toward activities associated with low-effort exertion is thought to play a key role in physical inactivity. Physical activity involves exerting physical effort, i.e., intensifying physical energy to achieve certain goals, such as increasing the force to lift a heavy object. This physical intensification is associated with the phenomenological experience of energy exertion. Higher effort perception is thought to be aversively valued by inactive individuals, inhibiting their engagement in regular physical activity. However, there is a lack of knowledge regarding the neural correlates of effort perception and how they relate to physical inactivity. It is crucial to gain insights into these neural correlates, especially to enhance our comprehension of the significance of effort minimization in physical inactivity. This project aims to decrease effort perception and improve the valuation of effort, incentivize regular physical activity, and improve overall health outcomes. Objective 1. Despite ongoing research, there is a lack of agreement on the neural mechanisms underlying effort perception as well as the role of sensorial feedback. Tasks EEG and fMRI aim to address this issue with original experimental methods in order to identify this neural mechanism. Hypothesis 1. Following A) muscle vibration and B) Induced ischemic paralysis and anesthesia, we expect decreased effort perception associated with a lower cortical S1 activation, unchanged activation in premotor structures, and preserved functional connectivity between premotor regions and S1. Objective 2. To unravel the neural interaction between efference copy and reafferent muscle spindle signals that contribute to effort perception Hypothesis 2. The neural correlates of effort perception involve interactions between premotor and sensory brain structures. Neural activation patterns of the brain regions implicated in effort perception vary depending on an individual's inclination to engage in physical activity. Objective 3. Task 3 will examine the potential of non-invasive brain stimulation techniques (TMS) to reduce effort perception in turn increase its perceived value quantified with the CR100 scale, the outcome variable of this study. Hypothesis 3. Vibration-induced desensitization of muscle spindles and the SMA cTBS reduce effort perception and improve the subjective value of physical effort.

Urinary incontinence is the most frequently observed lower urinary tract symptom (LUTS) in children with cerebral palsy (CP) (Samijn et al., 2016). Higher brain centers responsible for bladder function may be related to the presence of incontinence. The current pilot study is the first study of a research project focusing on correlations between brain damage and incontinence.