Echoplanar BOLD fMRI of brain activation induced by concurrent transcranial magnetic stimulation.
OBJECTIVE
The authors demonstrate the feasibility of combining transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) inside an MR scanner to noninvasively stimulate and image regional brain activity.


METHODS
Echoplanar blood oxygen level dependent (BOLD)-based fMRI studies of TMS response were performed on three human volunteers inside a standard 1.5 T MR scanner using independent computer control to interleave echoplanar image acquisition and stimulation of right thumb primary motor cortex with a nonferromagnetic TMS coil.


RESULTS
Significant (P< 0.001) response was observed in motor cortex under the TMS coil during stimulation compared to rest, as well in auditory cortex, the latter presumably due to the loud "snap" when the coil was pulsed.


CONCLUSIONS
Concurrent TMS stimulation and echoplanar BOLD fMRI imaging is possible. This method has potential for tracing neural circuits with brain imaging, as well as investigating the effects of TMS.
Bohning
D E
DE
Department of Radiology, Medical University of South Carolina, Charleston 29425, USA. bohninde@musc.edu
Shastri
A
A
Nahas
Z
Z
Lorberbaum
J P
JP
Andersen
S W
SW
Dannels
W R
WR
Haxthausen
E U
EU
Vincent
D J
DJ
George
M S
MS
D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D004558:Electric Stimulation; D004574:Electromagnetic Fields; D006225:Hand / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D009044:Motor Cortex / Q000033:anatomy & histology / Q000502:physiology*; D009622:Noise; D010812:Physical Stimulation; D050781:Transcranial Magnetic Stimulation