Non-invasive Brain Stimulation in Huntington's Disease

Overview

Huntington's disease is a disabling neurodegenerative disease. Patients present with involuntary movements of the body and cognitive symptoms like behavioral problem, difficulty in planning tasks, etc. No effective treatment is currently available for them apart from symptomatic therapy. Currently, studies are going on the effectiveness of noninvasive brain stimulation (NIBS) in neurodegenerative diseases. It is a mode of brain stimulation technique where current is delivered into the brain by placing electrodes into their scalp. Transcranial pulsed current stimulation (tPCS) is a new modality of noninvasive brain stimulation. It is a device that generates electrical impulses. The current generated from this device can stimulate underlying brain areas. The investigators have planned to study the feasibility of non-invasive brain stimulation via tPCS in these patients of Huntington's disease. At first, the investigators will rate their involuntary body movement by a standard scale, assess arm movements by a robotic device, assess speech with standard protocol, assess brain electrophysiology by electroencephalography (EEG) and will also do gait (walking) analysis. Next, the investigators will give them 2 week (20 min/day) stimulation via real tPCS (active stimulation) or placebo (sham stimulation). After 2 weeks of stimulation, the investigators will re-assess the patient using the same tools mentioned pre-stimulation. Each patient will receive real and placebo stimulation with a 1-month gap in between. They will not know whether they are receiving real stimulation or placebo. Assessment will be done before stimulation, after 2 week real stimulation and after 2 week sham stimulation.

The investigators have planned to study the feasibility of non-invasive brain stimulation via Transcranial pulsed current stimulation (tPCS) in patients of Huntington's disease. Anodal stimulation will be given to the brain area based on quantitative electroencephalography (qEEG) findings. Patients will be assessed clinically by standard rating scale (UHDRS) and by qEEG, KinArm and Gait - before and after 2 week (20 min per day) stimulation via tPCS or sham stimulation. The investigators have planned to assess- 1. Speech 2. Upper limb movement via KinArm. Standard KinArm testing protocol will be used which is used universally. 3. Gait via Gait Carpet (Zeno Walkway) 4. Quantitative electroencephalography (qEEG) 5. Scale for Huntington's disease (UHDRS) tPCS will be delivered through a pair of saline-soaked (0.9% NaCl) surface sponge electrodes. Anode will be placed on the scalp over the area based on qEEG findings. Participant's speech will be recorded using a head-mounted microphone (AKGc520) and a digital recording device (Zoom H4nPro) while performing the following calibrated tasks (Calibration involves a sound level meter placed at 15cm from the mouth while talker says 'ah' at 70dBA) - a. Prolonged 'ah'. b. Rapid repetitions of the sounds "puh", "tuh", and "kuh". c. Two productions of a sentence with selected speech sounds (s, sh, p, b, t, i, a, u, ae, ai). "She saw Patty buy two poppies." d. Two times louder production of a sentence with selected speech sounds. "She saw Patty buy two poppies." e. Repetition of a continuous vowel at normal and fast rates. 'eye-eye-eyeeye- eye' without making any voice breaks or pauses". f. Read aloud a section of a standard passage - standard rainbow passage g. Monologue. Talk for two minutes about an interesting vacation (or an interesting hobby or activity). The Zeno walkway will be used in conjunction with the ProtoKinetics Movement Analysis Software (PKMAS) . The walkway contains a series of pressure sensors to detect footfalls. These data will be captured and collated via the PKMAS software, resulting in numerous spatial, temporal and pressure-related gait parameters. Timed-up-and-go (TUG) task will be used, consisting of rising from chair, walking across the 20-foot gait carpet, turning around off the carpet, walking back and sitting down. This will be performed over 3 trials. Gait analysis provides various parameters as output such as stride length, line of progression, step length, toe-offs and other temporal and spatial parameters for analysis. Neurophysiological EEG signals will be recorded, eyes-closed, no-task, using g.Nautilus g.tec wireless system. The g.tech system uses earclip reference sensors. The subject will be in a quiet place with less light or electromagnetic perturbations. During the resting state recordings, patients are seated in a comfortable arm chair and will be instructed to keep relaxed, with their eyes closed for 5 min. A paired t test will be used to compare baseline data and post tPCS data. Descriptive analysis of the neurological examination findings will be provided.