The aim of this trial is to quantify the improvement of locomotion and equilibrium induced par tDCS in anode polarity position in post stroke hemiplegic patients.

This is a pilot prospective randomised crossover double blind study. 40 patients will be enrolled in two sites, with 20 patients each site.

The duration of this study is planned to be 25 months: 24 months will be for enrollment and 1 month for the follow-up.

The follow-up of patient comprises 3 visits, will be extended to 28 days for each patient:

• V1: inclusion visit:

After obtained an informed consent signed, the following analysis will be realized: a clinical assessment, quantify analysis of walking using 3D motion analysis system, assessment of equilibrium using force plate and functional abilities.

The patient will record him-self clinical scales and will respond auto-evaluation questionnaires. A cerebral magnetic resonance imaging and a blood collection of 5 ml will also be realized.

• V2-V3 (Locomotion /equilibrium assessment visit):

V2 and V3 will begin with tDCS experimental visit (EV) or tDCS placebo visit (PV), the visit order for each patient will be defined by randomization result.

During the 2 visits, the tDCS will be placed on the scalp of the patient. The anode will be placed at the hot spot of the tibialis anterior motor cortex area on the damage hemisphere, and the cathode will be placed at the controlateral orbit. The intensity of stimulation will be 2 mA.

In tDCS experimental visit, the stimulation will last 30 minutes. In tDCS placebo visit, the duration of the stimulation will only be 120 seconds, with the identical other conditions.

Before the beginning of the stimulation, a clinical assessment, a functional gait related activities evaluation and a 3D gait motion analysis associated with an evaluation of the equilibrium will be performed.

During the stimulation period, the gait and the equilibrium assessments, using 3D motion analysis will be done.

After the stimulation, the evaluations such as clinical, functional and motion analysis will be realized again.

The tDCS experimental visit and the tDCS placebo visit will be spaced one week.

Inclusion Criteria:

• Adults
• Unilateral stroke
• More than 6 months after stroke
• Ability to walk during 10 minutes without stopping
• Informed consent signed

Exclusion Criteria :

• Patient with pacemaker
• Claustrophobia (unable to perform a magnetic resonance imaging analysis)
• Patient with severe aphasia or severe cognitive disorder interfering the follow-up of the trial
• Neuro-orthopedic surgery history in the last 6 months on the studied paretic lower limb
• Epilepsy history in the last year
• Lack of medical insurance
• Adult patient under the care of a guardian
• Patient with progressive concomitant disease
• Patient with deep brain stimulation treatment (implantation of medical device)
• Patient with implantation of Intracranial metallic clip
• Patient with implantation of Intracranial stent
• Patient with implantation of ventriculoperitoneal derivation
• Patient with implantation of intracerebral or ocular prosthetic materials
• Patient with ferro-magnetic foreign object
• Patient with cochlear implant
• Patient with implantable cardioverter-defibrillator