title: The silent period threshold as a measure of corticospinal inhibition.
abstract: Corticomotor threshold is a clinically useful concept for defining motor cortex excitability using transcranial magnetic stimulation. Although the silent period duration can be a quantitative measure of corticospinal inhibitory function, its threshold value has not been formally determined. The authors studied 20 right-handed normal subjects and found that silent period threshold was a reproducible parameter that did not vary with age and sex. Its value was significantly lower with left-sided transcranial magnetic stimulation and right-hand recordings. The silent period threshold may be a novel parameter useful for future studies of cortical inhibitory function.
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore General Hospital, Singapore. gnrly@sgh.com.sg
authors.forename: Yew-Long
authors.initials: YL
authors.lastname: Lo
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fook-Chong
mesh_terms: D000328:Adult; D000368:Aged; D004558:Electric Stimulation / Q000379:methods; D004576:Electromyography / Q000379:methods; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology / Q000528:radiation effects*; D009433:Neural Inhibition / Q000502:physiology / Q000528:radiation effects*; D011712:Pyramidal Tracts / Q000502:physiology* / Q000528:radiation effects; D011930:Reaction Time / Q000502:physiology; D012016:Reference Values; D015203:Reproducibility of Results; D012684:Sensory Thresholds / Q000502:physiology* / Q000528:radiation effects; D013997:Time Factors