Journal
CEREBRAL CORTEX
Volume 19, Issue 7, Pages 1654-1665Publisher
OXFORD UNIV PRESS INC
DOI: 10.1093/cercor/bhn201
Keywords
corpus callosum; motor evoked potential; primary motor cortex; short and long latency interhemispheric inhibition; transcranial magnetic stimulation
Categories
Funding
- Canadian Institutes of Health Research [MOP 62917, DFF 88348]
Ask authors/readers for more resources
Interhemispheric inhibition (IHI) refers to the neurophysiological mechanism in which one hemisphere of the brain inhibits the opposite hemisphere. IHI can be studied by transcranial magnetic stimulation using a conditioning-test paradigm. We investigated IHI from 5 motor related cortical areas in the right hemisphere to the left primary motor cortex (M1). These areas are hand and face representations of M1, dorsal premotor cortex, somatosensory cortex, and dorsolateral prefrontal cortex. Test stimulus was delivered to the left M1 and conditioning stimulus (CS) was delivered to one of 5 motor related cortical areas in the right hemisphere. The time course of IHI, effects of different CS intensities and current directions on IHI were tested. Maximum IHI was found at interstimulus intervals of similar to 10 ms (short latency IHI, SIHI) and similar to 50 ms (long latency IHI, LIHI) for the motor related areas tested. LIHI could be elicited over a wide range of CS intensities, whereas SIHI required higher CS intensities. We conclude that there are 2 distinct phases of IHI from motor related cortical areas to the opposite M1 through the corpus callosum, and they are mediated by different neuronal populations.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available