This study's objective is to determine if electrical stimulation can safely reduced atrial fibrillation, which is an abnormal heart rhythm that begins in the top chambers of the heart. Electrical stimulation will be delivered to the wrists or in the ear. Participation will last about 6 weeks and require 3 clinic visits. Participants will be asked to wear a heart monitor and patch to monitor the heart rate and rhythm, keep a diary to collect information on atrial fibrillation, undergo randomization (being randomly assigned, like drawing straws) and use the study device per randomization assignment. Participants are randomized in a 1:1:1 fashion to a wrist worn study device, an ear piece study device or a sham wrist worn study device. A sham device looks like the real wrist worn device but does not deliver any electrical stimulation.

The purpose of this study is to examine the relationship between reflexes in the leg and the presence of neuropathic pain. The researchers are recruiting 30 individuals with spinal cord injury (SCI) total, 15 individuals with neuropathic pain due to SCI and 15 individuals without neuropathic pain. For this portion of the study, there are 2 visits. The first visit will examine cutaneous reflexes in the leg. During the second visit, the study team will assess sensation in the leg and administer questionnaires about pain, functioning, and quality of life.

The purpose of the second part of the study is to examine the effect of reflex training in the leg to decrease neuropathic pain. For this, the researchers are recruiting 15 individuals with neuropathic pain due to spinal cord injury to participate in the reflex training procedure. The study involves approximately 50 visits with a total study duration of about 6.5 months (3 months for baseline and training phases followed by 1 month and 3 month follow-up visits).

This study is designed to gain a better understanding and natural history of acute flaccid myelitis (AFM).

This study will include reviewing medical records to record information about the medications taken to treat AFM and your social history (smoking, alcohol and drug use). The results of lab tests, imaging studies and tests will also be collected to determine if you have any damage to your nerves that are done by your clinical care team to diagnose your AFM.

Samples from Mouth, nose, stool and blood will be collected as a part of this study. Any remaining spinal fluid that is in the lab from the spinal tap from clinical labs will also be collected. A neurological exam and tests to determine issues with muscles, functionality and strength after being diagnosed with AFM will also be performed as a part of this study.

Transcranial direct current stimulation (tDCS) has shown the potential to improve symptoms in patients with motor deficits, however its effects have not been consistent in randomized studies to date, limiting widespread adoption of this technology. A critical gap in our knowledge is a detailed understanding of how tDCS affects motor areas in the brain. We propose using tDCS while recording directly from motor cortex using subdural electrocorticography (sECoG) in patients undergoing deep brain stimulation surgery. We expect this novel approach to broaden our understanding of tDCS application and possibly lead to therapeutic advances in this population.

Transcranial magnetic stimulation (TMS) is often used to assess the excitability of the brain and the connectivity between the brain and peripheral muscles. However, less work has been completed with the portion of the brain controlling leg muscles. In addition, there appears to be more error and less reliability in these measures in those with stroke. This project aims to assess a battery of TMS-derived outcome measures to determine the most effective for those after stroke. This information is of critical importance as we use this technology to assess changes after rehabilitation post stroke and to understand the motor control of walking after neurologic injury.