Effect of Transcranial Direct Current Stimulation (tDCS) on the Excitability of the Diaphragmatic Primary Motor Cortex

Institut National de la Santé Et de la Recherche Médicale, France12 enrolled

Overview

Transcranial direct current stimulation (tDCS) is a non invasive, painless, harmless way to modulate cerebral cortex excitability. It was shown that anodal stimulation increases cortical excitability and the cathodal one decreases it (Nitsche and Paulus, 2000; Lang et al. 2004). To date, there is no data in the literature regarding the effect of tDCS on the corticodiaphragmatic pathways. This preliminary study aims to test and validate the modulating effect of tDCS on the excitability of the primary motor cortex dedicated to the hemi-diaphragms in a sample of healthy subjects, as a prelude to further large studies in patients with paretic hemi-diaphragms. Diaphragmatic motor evoked potentials will be assessed before and after applications of three different modalities of tDCS (anodal, cathodal and placebo).

We therefore expect to observe a significant increase of the mean values of the right hemidiaphragm's MEP's amplitudes after application of anodal tDCS compared to the baseline MEP obtained before this treatment.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

TRIPLE

Enrollment

Conditions

Excitability of Diaphragmatic Primary Motor Cortex

Interventions

Eligibility

Sex: MALEMin age: 18 YearsMax age: 35 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Right handed, * Healthy male volunteers * Aged ≥ 18 and ≤ 35 years * No history of neurological or respiratory disease * BMI (body mass index \< 30) Exclusion Criteria: * Female sex * Vulnerable people as defined in the provisions relating to biomedical researches and described in the Code of Public Health. * Recent or ongoing use of antibiotic drugs, antidepressants or psychotropic drugs. * Recent hospitalization (within 3 months). * No affiliation to a social security system.

Outcomes

Primary Outcomes

Change in the right side hemi-diaphragm's motor evoked potentials (MEPs) before and after applications of three different modalities of tDCS (anodal, cathodal and placebo) upon the left primary motor cortex.

The facilitating effect of tDCS in Anodal stimulation mode (a-tDCS) on the excitability of the left diaphragmatic primary motor cortex would result in a significant increase of the amplitude of the right hemidiaphragm motor evoked potentials (MEPs) (obtained by Transcranial magnetic motor stimulation of the left diaphragmatic primary) after this treatment.

Time frame: Baseline MEPs (before tDCS), Post 0 MEPs (immediately after tDCS) and Post 10 MEPs (10 min after tDCS).