modulation and assessment of mental flexibility in dysexecutive brain patients

Conditions: Dysexecutive Syndrome

Summary: this project aims to (1) define and characterize brain networks of cognitive flexibility amongst patients with frontal lesions; (2) quantify the effects of ecological cognitive trainings and brain stimulation on behavioral performance and brain networks; (3) identify predictive markers of effective rehabilitation (patients)

decision making impairments and perseveration are frequently observed in patients with frontal lobe lesions, associated with overall chronic and serious deficits in executive functions. in order to improve mental flexibility, patients can benefit from reeducation based on regular training of executive functions along with a non-invasive brain stimulation. one of the key areas for such processing is the prefrontal cortex. previous studies have shown however that maintaining a good level of mental flexibility in complex tasks involves a dynamic integration of several brain areas distributed in large networks. these areas in cooperation can be solicited by a multi-modal intervention such as motor-cognitive tasks associated with a transcranial stimulation. the goal of the present project is to develop a new rehabilitation program and to assess its impact in comparison with current programs. the investigators will also develop new methods to measure long term cerebral modifications induced by these programs. this goal will be reached by: 1) the identification of the brain networks of mental flexibility. 2) the assessment of multimodal task effects associated with or without a transcranial brain stimulation. behavioral (performance in executive tasks) and functional (parameters of cerebral functional connectivity networks at rest) measures will be used. 3) the identification of mental flexibility predictors. the goal will be to find which initial individual's parameters of brain functional connectivity at rest could predict an optimal level of mental flexibility after training. this project aims at improving the quality of life in the brain-damaged population; impact that could eventually extend to the other parts of the population.

Eligibility criteria:
inclusion criteria: * affiliated to social security * signed informed consent * mother tongue: french * right handed (edimburg scale) * frontal traumatic brain injury or stroke responsible for a dysexecutive syndrome assessed by the grefex battery. exclusion criteria: * claustrophobia * addiction * major hearing or visual loss * hearing prosthesis * metal intraocular implant * cardiac prosthesis * high blood pressure * severe cardiac insufficiency * uncompensated thyroid disorders * major neuropsychological disorder * family or personal history of epilepsy * pregnancy * female subject of childbearing age not receiving effective contraception. * participation in another experimental protocol involving brain stimulation within the last 4 weeks * person under the protection of justice, tutorship or curatorship * mri contraindication * refusal to be informed of a new anomaly detected during the mri examination * other traumatic brain injury or neuropsychological disorder

Keywords: cognitive rehabilitation mental flexibility ecological tasks functional connectivity electroencephalogram traumatic brain injury cerebrovascular accident