Please select the eligibility criteria that correspond to the clinical trial below.
Title: a Controlled, Randomized Study Evaluating the Immediate Effect of One tDCS Session on Quadriceps Strength in Hemiparetic Patients.
Brief Summary: Previous studies show that one session of tDCS allow to improve muscle strength in hemiparetic patients in anodal condition. We test a new electrods configuration : a anodale stimulation opposite to the cortical representation area of the injured hemisphere and a simultaneous stimulation opposite to the homonyme the cortical representation area of the healthy hemisphere. This approach seems to be the best relevant electrods configuration in order to restore the inter-hemispheric balance.

We hypothesis that one session of tDCS with this electrods configuration allow to improve paretic quadriceps strength in hemiparetic patients after stroke.


Options:
A: Inclusion Criteria:

* First time clinical ischemic or hemorrhagic cerebrovascular accident (radiologically confirmed)
* Demonstrates adequate balance while wearing a hand restraint on the unaffected arm
* Ability to stand from a sitting position and ability to stand with or without upper extremity support
* Stroke onset at least 6 months prior to study enrollment

Exclusion Criteria:

* Significant pre-stroke disability
* Any substantial decrease in alertness, language reception, or attention that might interfere with understanding instructions for motor testing
* Excessive pain in any joint of the paretic extremity
* A terminal medical diagnosis consistent with survival of less than 1 year
* Advanced liver, kidney, cardiac, or pulmonary disease
* Coexistent major neurological or psychiatric disease (including epilepsy)
* A history of significant alcohol or drug abuse in the prior 3 years
* Use of neuropsychotropic drugs - such as antidepressants
* Patients may not be actively enrolled in a separate intervention study targeting stroke recovery
* Patients may not have already received constraint-induced movement therapy and/or tDCS treatment for stroke
B: Inclusion Criteria:

* first episode of unilateral stroke
* time since stroke less than 3 months, i.e., acute or subacute stage
* initial motor part of upper limb of FMA score ranging from 10 to 40, indicating severe to moderate movement impairment
* no serious cognitive impairment (i.e., Mini Mental State Exam score \> 23)

Exclusion Criteria:

* pregnant or breastfeeding women
* aphasia that might interfere with understanding instructions
* major health problems or poor physical conditions that might limit participation
* currently participation in any other research. Potential participants will be also excluded if they have any contraindication to fMRI scanning including claustrophobia, seizures, the presence of pacemaker, mental elements (e.g., steel nails) inside the body or in the eyes, and excessive obesity.
C: Inclusion Criteria:

* Chronic (\> 6 months) stroke patient
* Aged 18-79 years
* Motor deficit in the upper limb due to the stroke

Exclusion Criteria:

* Absence of recordable MEPs from the ADM after TMS
* Absence of voluntary movement (Fugl-Meyer \< III)
* Head injury or the presence of intracranial metal or intracranial lesions
* History of cranial irradiation
* History of epilepsy
* Presence of a pacemaker
* Taking anticonvulsant or neuroleptic medication
* Substance abuse
* Inability to understand instructions
* History of psychiatric disorders
D: Inclusion Criteria:

* written consent
* hemiparetic patient after stroke in chronic phase (\> 6 months)
* capacity to walk with or without technical assistance
* following rehabilitation program for lower limbs

Exclusion Criteria:

* patient with bilateral brain lesion, cerebellar syndrom, and apraxia and/or aphasia
* previous orthopedic surgery in paretic lower limb (\<6 moths)
* usual tDCS contraindications
* pregnant woman

Answer: D