Effect of tACS on the Recovery of Motor Control of the Upper Limb and Cerebral Connectivity in Chronic Stroke Patients

Summary

This project seeks to evaluate the effect of transcranial alternating current stimulation (tACS) on the recovery of motor control of the upper limb and associated neuronal synchrony during a 14-sessions (5-week) rehabilitation program for adult patients with diagnosis of stroke at chronic stage. Specifically, the stimulation on Gamma ranges, because the evidence available so far allows us to propose that the tACS in the Gamma range (around 70 Hz) facilitates motor execution.

For this purpose, the experimental approach involves active (70 Hz in Gamma rhythm and 7 Hz, Theta rhythm) and sham tACS together with an analytical and integrated motor training with a double-blind and randomized design.

Our hypothesis is that Gamma frequency tACS restores neuronal synchrony in Beta range, which enhances the upper limb motor recovery associated with a training program.

Using specific motor control parameters, clinical scales and electroencephalography, the immediate and long-term (3 months after finished the training) behavioral and neurophysiological effect of this new neurostimulation paradigm (tACS plus training) for motor rehabilitation of stroke will be established.

Conditions

• Chronic Stroke
• Rehabilitation

Interventions

DEVICE

transcranial alternating current stimulation 70 Hz

Transcranial alternating current stimulation in the head above the motor cortex area of one side of the brain, according to the hemiparesis side. Electrodes with 3.14 cm2 of stimulation area will be used, therefore, the initial current intensity will be 0.21 mA, with a current density of 0.07 mA / cm2. The current intensity will be adjusted to the tactile sensory threshold and phosphenes of each patient, with in order to reduce such sensory effects, but considering that the decrease in current will not be greater than 10% of the initial intensity, in order to obtain a comparable configuration between subjects. The frequency stimulation will be 70 Hz

BEHAVIORAL

Training

Training of the upper limb with specific kinematic and kinetic tasks plus functional training

DEVICE

transcranial alternating current stimulation 7 Hz

Transcranial alternating current stimulation in the head above the motor cortex area of one side of the brain, according to the hemiparesis side. Electrodes with 3.14 cm2 of stimulation area will be used, therefore, the initial current intensity will be 0.21 mA, with a current density of 0.07 mA / cm2. The current intensity will be adjusted to the tactile sensory threshold and phosphenes of each patient, with in order to reduce such sensory effects, but considering that the decrease in current will not be greater than 10% of the initial intensity, in order to obtain a comparable configuration between subjects. The frequency stimulation will be 7 Hz

DEVICE

transcranial alternating current stimulation Sham

Transcranial alternating current stimulation in the head above the motor cortex area of one side of the brain, according to the hemiparesis side. Electrodes with 3.14 cm2 of stimulation area will be used, therefore, the initial current intensity will be 0.21 mA, with a current density of 0.07 mA / cm2. The current intensity will be adjusted to the tactile sensory threshold and phosphenes of each patient, with in order to reduce such sensory effects, but considering that the decrease in current will not be greater than 10% of the initial intensity, in order to obtain a comparable configuration between subjects. The stimulation will be turn on for 30 seconds (at 70 Hz)

Sponsors & Collaborators

• Universidad Metropolitana de Ciencias de la Educacion

  lead OTHER

Principal Investigators

• Juan J Mariman, Ph.D · Universidad Metropolitana de Ciencias de la Educacion

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-05-02

Primary Completion

2025-04-07

Completion

2025-04-07

Countries

• Chile

Study Locations