3 Clinical Trials for Various Conditions
The goal of this research study is to learn how the brain areas that plan and control movement interact with the areas responsible for hearing and perceiving speech in healthy adults and people who have had cerebellar strokes. The main questions it aims to answer are: 1. What regions of the brain's sensory systems show changes in their activity related to speech? 2. To what extent do these regions help listeners detect and correct speech errors? 3. What is the role of the cerebellum (a part of the brain in the back of the head) in these activities? Participants will be asked to complete several experimental sessions involving behavioral speech and related tests and non-invasive brain imaging using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI).
Transcranial magnetic stimulation (TMS) interventions could feasibly strengthen residual corticospinal tract (CST) connections and enhance recovery of paretic hand function after stroke. To maximize the therapeutic effects of such interventions, they must be delivered during poststroke brain activity patterns during which TMS best activates the residual corticospinal tract and enhances neural transmission within it (i.e., brain state-dependent TMS). In this study, the investigators will test the feasibility of real-time, personalized brain state-dependent TMS in neurotypical adults. Participants will visit the laboratory for one day of testing. Upon arrival, participants will provide their informed consent; afterwards, they will complete eligibility screening. The investigators will then place recording electrodes on the scalp using a swim-type cap and on the left first dorsal interosseous, abductor pollicis brevis, and extensor digitorum communis muscles. After determining the location at which TMS best elicits muscle twitches in the left first dorsal interosseous, the investigators will determine the lowest possible intensity at which TMS elicits muscle twitches at least half of the time in this muscle. Then, the investigators will deliver 6 blocks of 100 single TMS pulses while the participant rests quietly with their eyes open; stimulation will be delivered at an intensity that is 20% greater than the lowest possible intensity at which TMS elicits muscle twitches at least half of the time. Afterwards, the investigators will use the muscle and brain activity recordings acquired during these 6 blocks to build a personalized mathematical model that identifies which patterns of brain activity correspond to the largest TMS-evoked muscle twitches. The investigators will then use this model to detect the occurrence of these brain activity patterns in real-time; when these patterns are detected, single TMS pulses will be delivered. Afterwards, all recording electrodes will be removed, participation will be complete, and participants will leave the laboratory. The investigators will recruit a total of 16 neurotypical adults for this study.
This is a single-arm, two-visit, non-randomized, cross sectional study identified as an intervention due to the use of a single bout of aerobic exercise to assess cerebrovascular function under the NIH rules. This study is not masked and its primary purpose is to develop a basic science understanding of the relationship between cerebrovascular health and balance control with aging. This study will involve 102 individuals classified as younger adults, middle-aged adults, and older adults who are neurotypical and cognitively normal. The primary outcome from a clinical trials perspective will be cerebrovascular response to a bout of aerobic exercise (i.e. change in cerebral blood flow with the performance of aerobic exercise on a recumbent stepper exercise machine). Non-interventional outcomes will be EEG measures of cortical activity and biomechanical kinetic and kinematic data recorded during standing balance reactions, as well as biological blood samples for genomic analysis.