title: Visual deprivation effects on human motor cortex excitability.
abstract: Single and paired-pulse transcranial magnetic stimulation (TMS) were applied to the motor cortex of 12 healthy volunteers, who were instructed to relax under eyes-open and eyes-closed conditions with room lights on and after 30 min of blindfolding. Compared to the eyes-open condition, significantly larger motor-evoked potentials and less intracortical inhibition were observed during blindfolding. Visual deafferentation changes resting human motor cortex excitability and might be a novel way to promote brain plasticity. These results raise the issue of how widespread the effects of temporary deafferentation may be and whether they are mediated by discrete or diffuse systems. These findings also illustrate an important potential confound in TMS studies of the motor cortex.
authors.affiliation: Brain Stimulation Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA. feleoness@yahoo.com
authors.forename: Fidias E
authors.initials: FE
authors.lastname: Leon-Sarmiento
authors.forename: William
authors.initials: W
authors.lastname: Bara-Jimenez
authors.forename: Eric M
authors.initials: EM
authors.lastname: Wassermann
mesh_terms: D003624:Darkness; D019054:Evoked Potentials, Motor / Q000502:physiology*; D007839:Functional Laterality; D006801:Humans; D008027:Light; D008280:Magnetics; D009044:Motor Cortex / Q000502:physiology* / Q000528:radiation effects; D012683:Sensory Deprivation / Q000502:physiology*; D014785:Vision, Ocular