Brain Excitability and Connectivity in Sensory-motor Pathways in ALS

Evaluation and Characterization of Infraclinical Sensory Deficits in Amyotrophic Lateral Sclerosis by Brain Imaging and Electrophysiology

The main objective is to determine the origin of somatosensory alteration in patients with ALS and to evaluate its impact on brain activity by coupling different imaging modalities and indirect electrophysiology.

The secondary objective is to evaluate whether the observed functional changes in MEG / EEG and functional MRI correlate with structural lesions revealed with diffusion MRI (anatomo-functional connectivity of the brain).

Somatosensory evoked potentials (SEPs) produced by ulnar nerve electrical stimulation will be collected with combined MEG and EGG.

Functional MRI will be performed during electrical stimulation of ulnar nerve and during mechanical vibration of ADM tendon.

Brain diffusion MRI will be performed. Anatomical MRI will be done for source location. Brain resting state activity will be recorded with MEG/EEG and fMRI.

Inclusion Criteria:

• ALS, MRC score ≥ 4 at least in one hand
• Controls: no history of neurological disorders, right-handed

Exclusion Criteria:

• contraindication to MRI