The National Institute of Neurological Disorders and Stroke, part of the National Institutes of Health, is looking for individuals to participate in clinical studies. Participating in clinical trials allows you to play an active role in research on the nature and causes of many disorders of the brain and nervous system, and to possibly help physician-scientists develop future treatments. The information below is designed to help you quickly learn about actively recruiting research studies for which you or someone you know may be eligible.

Description:

Objective: To use resting state functional connectivity (FC) as a biomarker of synaptic modulation by repetitive transcranial magnetic stimulation (rTMS) in paradigms intended to improve memory and learning and to pilot one such paradigm for improving memory in traumatic brain injury (TBI) patients. Ancillary outcomes include the effects of rTMS on the explicit and implicit memory systems and the potential effects of manipulating one system on the other. Study population: Healthy adult volunteers and patients with TBI Design: The study contains 3 experiments. Experiment 1 is designed to establish the number of rTMS sessions required to produce a meaningful change in resting parietohippocampal FC in healthy subjects. Experiment 2 will apply this information to an experiment aimed at enhancing fronto-striatal FC and, as a secondary outcome, enhancing implicit memory. This intervention will be contrasted with parietal stimulation and a negative control condition (vertex stimulation) in a between-groups design. In Experiment 3, we will adapt a paradigm used by others in healthy subjects to amnestic TBI patients in an effort to enhance parieto-hippocampal FC and, as a secondary outcome, explicit memory. This will be compared to negative control (vertex) stimulation in a within-subjects design Outcome measures: The primary outcome measure is the change in FC produced by serially applied rTMS. Secondary measures will be changes in explicit and implicit memory performance. We will explore whether white matter integrity predicts changes in FC in healthy subjects and patients.

Eligibility Criteria:

- INCLUSION: Healthy individuals in Experiments 1 and 2. Age 18-50 (inclusive) - English speaking and writing Patients in Experiment 3 - Age 18-50 (inclusive) - English speaking and writing - History of mild to moderate TBI - Performance 1 standard deviation below age-adjusted population norms on the CVLT-2 within the past year from the date of visit. EXCLUSION CRITERIA: Healthy subjects - Any current major neurological or psychiatric disorder such as (but not limited to) stroke, Parkinson disease, Alzheimer disease, schizophrenia or major depression - History of seizure - Medications acting on the central nervous system - Ferromagnetic metal in the cranial cavity or eye, implanted neural stimulator, cochlear implant, or ocular foreign body - Implanted cardiac pacemaker or auto-defibrillator or pump - Non-removable body piercing - Claustrophobia - Inability to lie supine for 1 hour - Pregnancy, nursing, or plans to become pregnant during the study. - Members of the NINDS Behavioral Neurology Unit (BNU) - For Experiment 2: Participation in Experiment 1 TBI Patients - Any current major neurological or psychiatric disorder unrelated to TBI, such as (but not limited to) stroke, Parkinson disease, Alzheimer disease, schizophrenia or major depression. - History of seizure - Inability to give informed consent - Ferromagnetic metal in the cranial cavity or eye, implanted neural stimulator, cochlear implant, or ocular foreign body - Implanted cardiac pacemaker or auto-defibrillator or pump - Non-removable body piercing - Claustrophobia - Inability to lie supine for 1 hour - Pregnancy, nursing, or plans to become pregnant during the study. - Members of the NINDS Behavioral Neurology Unit (BNU) - For Experiment 2: Participation in Experiment 1

Study Design:

Study Location:

Maryland