Dr. Michael J. Grey, University of East Anglia, Norwich, United Kingdom
Novel tools for the rapid online data acquisition of TMS corticospinal excitability
Neuroplasticity is believed to be critical for neurorehabilitation. One way to assess neuroplasticity is to use TMS to measure corticospinal excitability (CSE). Whereas both stimulus response (SR) curves and CSE maps provide more information than does a single set of MEPs at fixed intensity, their use is restricted by the time it takes to acquire the data (typically 15+ min). This time is longer than a participant’s ability to maintain attention and it is too time consuming for use in the clinical setting. As a result, these techniques have been restricted to the laboratory environment. In this talk I will demonstrate that SR curve and CSE map data may be acquired in less than two minutes with the Magstim Rapid stimulator (biphasic pulses) and less than 4 minutes with the Magstim 200 stimulator (monophasic pulses). This is achieved by reducing the interstimulus interval (ISI), optimising the number of stimuli and pseudorandomising the stimulation intensity (for SR curves) or stimulation position (for CSE maps). Importantly, the rapid acquisition of curve and map data allow the resulting curve/map to be visualised whilst the participant is in the room rather than off-line, thus ensuring data quality. The rapid acquisition of TMS measures is now possible in the laboratory, but perhaps more importantly, these methods provide an opportunity to evaluate neuroplasticity in the clinical environment.
Associate Professor Shellie A. Boudreau, PhD
Professor Thomas Graven-Nielsen, DMSc, PhD
Director of Center for Neuroplasticity and Pain (CNAP)