Therapeutic Effects of Transcranial Alternative Current Stimulation (tACS) in Chronic Post Stroke Hemianopia (HEMIANOTACS)
Hemianopsia
About this trial
This is an interventional treatment trial for Hemianopsia
Eligibility Criteria
Inclusion Criteria:
Patient aged 18 and over
- Patient with homonymous lateral hemianopia with brain injury acquired for at least 3 months and at most 5 years after ischemic stroke, cerebral hematoma
- Patient able to understand French both orally and in writing
- Patient giving free, informed and written consent
- Absence of a neurological disease interfering with the passing of tests
Non-inclusion criteria :
- Patients subject to a legal protection measure (safeguarding of justice, guardianship and trusteeship, protected adults)
- Pre-existing severe ophthalmological disorders (ophthalmic consultation before inclusion) pre-existing visual field defects, monocular visual acuity less than 5/10, severe oculomotor disorders
- Contraindication of tACS and / or magnetic resonance imaging (pacemaker or implantable defibrillator, intracranial electrodes or other intracranial implant, cranial vault anomalies facing stimulation electrodes (plates, prostheses, uncovered skull)
- Pregnant women and nursing mothers
- Recruitment in other interventional studies for the duration of the participation.
- Non-affiliation to a social security scheme (excluding AME) or non-beneficiary of such a scheme
Healthy participants inclusion criteria are the following:
- Healthy Subject 18 years and older
- Healthy subject able to understand French both orally and in writing
- Healthy subject who has given free and informed consent and writes
Healthy participants non-inclusion criteria are the following:
- Severe neurological, psychiatric, physical, or ophthalmological disorders that interfere with the normal performance of tests and study tasks
- Contraindication to magnetic resonance imaging (pacemaker or implantable defibrillator, intracranial electrodes or other intracranial implant, abnormalities of the cranial vault opposite stimulation electrodes (plates, prostheses, uncovered skull)
- Recruitment in other interventional studies for the duration of the participation.
- Pregnant women and nursing mothers
- Non-affiliation to a social security scheme (excluding AME) or non-beneficiary of such a scheme
Sites / Locations
Arms of the Study
Arm 1
Arm 2
Arm 3
Active Comparator
Active Comparator
Sham Comparator
tACS stimulation of the right frontal region
tACS stimulation of the occipito-parietal region
TACS stimulation of the right frontal (FEF)
Active tACS stimulation of the right frontal region (around the right FEF, EEG electrode FC2) at a high-beta frequency (30 Hz) with the goal of visibly training EEG recordings, frontal oscillatory activity and right fronto-parietal synchrony (FEF-IPS, or between FC2 and P4 electrodes) in the high-beta band (~ 30 Hz) which facilitates attentional orientation and visual perception in the two visual hemi-fields, but more particularly the targets present on the blind field of vision.
Active tACS stimulation of the occipito-parietal posterior contralesional region(around the right IPS, EEG electrode P4), at an alpha frequency (10 Hz) which will induce on the EEG recordings an oscillatory drive in the alpha band ( ~ 10Hz) and an increase in synchrony at this frequency band on the stimulated posterior occipital and parietal lobe (EEG electrodes P4 and 02), but also, by transcallosal push-and-pull phenomena, a desynchronization effect of the contralateral posterior occipital and parietal area (EEG electrodes P3 and 01), which will facilitate attention orientation and target detection in the blind visual field of view.
. Condition TACS stimulation of the right frontal (FEF) at a high-beta frequency (30 Hz) for half of the patients and unilateral occipital cortex (right / left) at an alfa frequency (10 Hz) for the other half . This condition will control the possible placebo effects of tACS stimulation and the potential effects of visual field enhancement with repetition of perimetry tests. This condition will also verify the lack of changes in cerebral rhythm activity in the case of an application without effective electrical current.