Evaluation of the Impact of Laterality on Cerebral Activation During a Motor Task of the Upper Limb Using fNIRS Technology in Healthy Subjects

Stroke frequently leads to upper limb deficit. The recovery of motor skills depends on many factors including laterality. The literature shows that cerebral activation during motor tasks differs depending on whether one is right-handed or left-handed and whether one uses the dominant hand or not. These differences probably lead to different recovery mechanisms depending on the side of the lesion and the laterality. An imaging technique is particularly suitable for exploring these different mechanisms: fNIRS (Functional Near Infra Red Spectroscopy). This method allows (like fMRI) to study cerebral neurovascular coupling. It is based on the fact that an activated brain region increases its local blood flow. Oxygenated (HbO) and deoxygenated (HbR) hemoglobin absorb infrared light and it is then possible to identify the cerebral cortical regions involved in a given task. This technique therefore makes it possible to study cerebral activation under more ecological conditions than fMRI and is thus particularly suitable for exploring rehabilitation techniques.

This research aims to study and compare in healthy subjects, using an fNIRS apparatus, the brain regions involved in the performance of different motor tasks according to the laterality of the task and the subject.

The investigations will be carried out by the principal investigator or by specialized technicians from the neurology functional exploration department.

Stroke frequently leads to upper limb deficit. The recovery of motor skills depends on many factors including laterality. The literature shows that cerebral activation during motor tasks differs depending on whether one is right-handed or left-handed and whether one uses the dominant hand or not. These differences probably lead to different recovery mechanisms depending on the side of the lesion and the laterality. An imaging technique is particularly suitable for exploring these different mechanisms: fNIRS (Functional Near Infra Red Spectroscopy). This method allows (like fMRI) to study cerebral neurovascular coupling. It is based on the fact that an activated brain region increases its local blood flow. Oxygenated (HbO) and deoxygenated (HbR) hemoglobin absorb infrared light and it is then possible to identify the cerebral cortical regions involved in a given task. This technique therefore makes it possible to study cerebral activation under more ecological conditions than fMRI and is thus particularly suitable for exploring rehabilitation techniques.

This research aims to study and compare in healthy subjects, using an fNIRS apparatus, the brain regions involved in the performance of different motor tasks according to the laterality of the task and the subject.