View clinical trials related to Healthy Volunteers.
Filter by:Background: Transcranial magnetic stimulation (TMS) is form of non-invasive brain stimulation. It is approved to treat depression. TMS may help decrease drug craving. It is important to understand how TMS affects the brain. Such a better understanding would help to design ways to treat drug addiction. Objectives: To learn how TMS affects the brain when it stimulates an area in the front of the brain. Also, to see how the stimulation affects the area stimulated and other connected areas. Eligibility: Healthy, right-handed adults ages 18 60 who are non-drug users. Design: Participants will be screened under protocol 06-DA-N415. Participants will have at least 3 visits. The first visit will last about 3 hours. All other visits will last up to 6 hours. Participants cannot use drugs or alcohol at least 24 hours before a visit. They cannot have more than half a cup of a caffeinated drink at least 12 hours before a visit. Each visit will include a brief medical history update, urine test for drugs and pregnancy (if female), a breath test for alcohol and smoking, and questionnaires. Participants will have a TMS orientation visit. A wire coil will be placed on the head. An electrical current will pass through the coil to create a magnetic pulse that stimulates the brain. The other visits will include 2 sessions of TMS-MRI. Participants will lie on a table that slides into a cylinder. The TMS coil and the MRI coil will be placed over the head. Pictures will be taken of the brain with and without stimulation. Participants will complete a questionnaire about how they feel before and after each TMS session and in a follow-up call 2 3 weeks after their last session.
The purpose of this study is to investigate the beneficial effects of regular exercise and the impact of food supplement carnosine on cognitive, motoric and metabolic functions as well as on specific biologically active substances in volunteers with subjective (SCI) or mild (MCI) cognitive impairment, as well as in patients in early stages of Parkinson's disease. The investigators assume the immediate intervention-associated health benefit for volunteers.
Although most ground studies showed that an egocentric reference frame better supports spatial orientation, it is not proven it will be the same during weightlessness. Although it might justify that visuomotor performance will be better supported by egocentric target cueing under altered gravity conditions, the fact that exocentric target cueing induces less head movements and called for least attentional and physiological workload could be the key factors for a more efficient task localization process. Moreover, weightlessness can induce spatial disorientation, which can be additionally influenced by the intrinsic and extrinsic spatial reference frames (Gurfinkel et al., 1993; Glasauer & Mittelstädt, 1997, 1998; Harm et al., 1998; Lipshits et al. 2005). We expect that during weightlessness the workload will be the key factor and thus we hypothesize that an exocentric target cueing will outperform egocentric target cueing. To test this hypothesis, and find out which presentation scheme for target cueing (EGO, EXO, ED) contributes most to an efficient visual search, performance to a visuomotor task will be evaluated during parabolic flights in normogravity (1g), hypergravity (1.8g) and microgravity (0g). The visuomotor performance will be assessed by a multi-directional tapping task as defined by ISO9241-9, which requests for motor responses by aimed pointing movements. Besides analyzing the pointing performance, different workload indices will be additionally assessed to evaluate the effort spent on visuomotor coordination. The attentional workload will be evaluated by the performance of a secondary task (visual reaction-time task), which needs to be conducted in parallel to the visuomotor task. Furthermore, the workload will be also assessed subjectively by the NASA TLX rating scale and physiologically, by analyzing the heart rate variability (HRV).
To produce hand's movement directed towards a target, the investigator must combine several sensory information, such as vision or proprioception. The posterior parietal cortex (PPC) is a region of the cortex involved in this multisensory integration. A lesion of the PPC cause a visuo-motor trouble called optic ataxia but these patients also have perceptual troubles. The aim of the study is to understand the different functions of the PPC and especially how the processes of spatial coding of the sensory information influences perception and motor planning. In this study, the investigator want to explore the sensory motor and the perceptual performance of patients with optic ataxia compared with healthy subjects, using 6 behavioral tests. Objectify the consequences of PPC impairment (visual-motor and perceptual consequences) on patients' quality of life and autonomy.
Currently, there is no available drug to treat the symptoms of neurodegenerative and vascular cognitive disorders that affect millions of people worldwide. Methylphenidate is indicated at high dose (1 mg/kg/day) in children having attention deficit and hyperactivity disorder (ADHD) and remains the best cognitive enhancer drug at lower dose. However, there is no proof of efficacy with chronic administration, outside ADHD, and concern remains about long-term cardiac and vascular risks in elderly and particularly in population with vascular risk factors and drug abuse in young people. Moreover, the effect appears to be very limited at the very advanced stage of dementia, for which the neuronal plasticity is too reduced to expect a benefit of training. Taken all together, we sought to develop a new paradigm of association of both pharmacological and non-pharmacological procedure to enhance the neuronal plasticity in order to expect a persistent effect on slight to mild cognitive disorders with benefit on ecological test (i.e. driving). Finally, short-term treatment would reduce the safety concerns. The concept will be to prove that low dose of methylphenidate associated with active cognitive training during 6 weeks can improve the cognitive function in healthy aged volunteers with a persistent effect at 3 months.
Background: People can feel different levels of pain. This may depend on social, cultural, and biological factors. These factors can also influence how people respond to each other, and how they judge other people s experiences. Researchers want to learn more about these relationships. Objective: To study if social and cultural factors lead to differences in pain experience and how pain is interpreted by other individuals. Eligibility: Healthy adults ages 18-60 Design: Participants will have 1 or 2 visits. Participants will be screened with a medical history and nursing assessment. Participants may have the following: Electric shock through small sticky pads on the arm, leg, or foot. Thermal stimulation. A device called a thermode will be placed on the arm, leg, or foot. A computer controls the thermode temperature. Lowering their hand into very cold water. Videos or pictures of the face will recorded while participants get painful stimulation. A test to record heart electrical activity. Small metal disc or sticky pad electrodes will be placed on the chest. Pulse rate and breathing measured. Sweating will be measured with two small sensors stuck on the hand. A test to measure the electrical activity of facial muscles. Small metal disk or sticky pad electrodes will be attached to the skin. Viewing pictures and/or videos of other people who get painful and nonpainful stimulation. Participants will make decisions about the images. They will respond by keyboard, mouse, or button. Eye tracking. A camera will measure participants pupil size and follow their eye movements. ...
Background: This study is designed to provide samples to help us study the genes your blood cells are making as well as the proteins, sugars, fats, vitamins and other metabolites found in your blood or urine. Blood samples may also be collected to make special cells. These are called induced pluripotent stem cells or iPSCs. Pluripotent stem cells are cells that can be converted into any type of cell. Researchers want to study in the lab iPSCs that are derived from blood samples. Objective: To collect samples to help study genes, proteins, sugars, fats, vitamins, and other metabolites found in blood or urine. Eligibility: Healthy volunteers and patients ages 18 and older Design: First-time research study participants at NIH will have an initial visit for this study that should last no more than 1 hour. All other visits should last 20 30 minutes. Participants will undergo a limited history and physical exam. Participants may have routine blood and urine tests. If participants are giving a blood sample, they must have a hemoglobin level checked in the past 12 months to make sure it is safe for them to give a blood sample for research. Participants may have a venous blood collection. They may do this at several visits. They will lie on a recliner or couch or sit in a chair. A needle will be placed into a vein in the hand or arm, using sterile techniques. Blood will be withdrawn into multiple syringes or tubes. Participants may be asked to provide urine in an appropriate container...
TRACERx Renal: This is a translational study, which, aims to develop prognostic and predictive biomarkers for patients with renal cell carcinoma (RCC). CAPTURE Sub-study: Covid-19 antiviral response in a pan-tumour immune monitoring study
This project pursues the validation of an innovative strategy to boost language learning, based on the benefits derived from sensorimotor training. The common belief of a rigid brain structure in adult life had to be reconsidered during the last decade. After training, local increase in cerebral cortex volume and thickness, the part of the brain containing neuronal cells and synapses, has been documented. Research has established that brain structures active during training expand while learning and return to baseline afterwards. The transient structural increase is thought to reflect "work in progress" within areas involved in learning, meant to integrate new skills in existing neural circuitries, via strengthening and/or selection of local neuronal connections. My main hypothesis is that other functions, as long as they rely on the activity of the same brain territories, can take advantage of this "work in progress". To use an allegory, imagine the restauration of a building (brain area). It can start after the request of improvements from some of the residents (trained function) and then become the occasion for other tenants (other functions) to see realized also their own wish for improvements. In the end everybody will benefit from the restauration, provided that they all live in the same building and everybody has posed their requests during the "work in progress". Out of the allegory, living in the same building means neural overlap of functions in the brain. The case of motor and linguistic systems represents, from this perspective, a unique opportunity. State-of-the-art research 1) proved the existence, and described the temporal evolution of brain plastic changes during sensorimotor learning, and 2) documented neural overlap and functional interactions of motor and linguistic systems. This posits solid bases for a crucial step forward, gravid of important consequences and applications. This project aims to take this step forward by directly testing the innovative hypothesis that brain changes induced by sensorimotor learning induce benefits for linguistic functions relying on the same brain territories.
It is now widely accepted that autism is linked to a developmental disorder and cerebral function. Our research team (UMR U930 INSERM, François-Rabelais University of Tours, whom Pr F Bonnet-Brilhault is responsible for team "Autism") hypothesizes that atypical sensory information processing, especially auditory and / or visual information, could underly the symptoms observed in autism. A better knowledge of the typical development of the sensory and cognitive processes must therefore make it possible in the long term to identify the abnormalities linked to the autism spectrum disorders (ASD). Studies in healthy subjects are therefore necessary in order to identify neurophysiological indices of cerebral functioning and to study their evolution during normal development, making it possible in the future to compare with populations of subjects with ASD. The investigators intend to study the development of all the cognitive processes involved in the processing of sensory and, in particular, auditory and visual information in humans: from low-level perception processes to higher-level cognitive processes (attention, emotion, language, prediction, ...). For this the investigators will use non-invasive neurophysiological explorations (EEG, eye tracking) as well as neuropsychological explorations (Questionnaires or spontaneous language recording). A better understanding of the pathophysiological mechanisms underlying the symptoms observed in autism could ultimately lead to the development of new specific therapeutic strategies, particularly in the field of exchange and development therapy or cognitive remediation .