BOLD-f MRI response to single-pulse transcranial magnetic stimulation (TMS).
Five healthy volunteers were studied using interleaved transcranial magnetic stimulation/functional magnetic resonance imaging (TMS/fMRI) and an averaged single trial (AST) protocol. Blood oxygenation level-dependent (BOLD)-fMRI response to single TMS pulses over the motor cortex was detectable in both the ipsilateral motor cortex under the TMS coil and the contralateral motor cortex, as well as bilaterally in the auditory cortex. The associated BOLD signal increase showed the typical fMRI hemodynamic response time course. The brain's response to a single TMS pulse over the motor cortex at 120% of the level required to induce thumb movement (1.0%-1.5% signal increase) was comparable in both level and duration to the auditory cortex response to the sound accompanying the TMS pulse (1.5% -2.0% signal increase).
Bohning
D E
DE
Functional Neuroimaging Research Division, Department of Radiology, Medical University of South Carolina, Charleston, South Carolina 29425, USA. bohinde@musc.edu
Shastri
A
A
Wassermann
E M
EM
Ziemann
U
U
Lorberbaum
J P
JP
Nahas
Z
Z
Lomarev
M P
MP
George
M S
MS
D000328:Adult; D001931:Brain Mapping; D055590:Electromagnetic Phenomena; D019054:Evoked Potentials, Motor / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D012016:Reference Values; D012680:Sensitivity and Specificity