TY - JOUR

T1 - Charting the excitability of premotor to motor connections while withholding or initiating a selected movement

AU - Kroeger, Johan

AU - Bäumer, Tobias

AU - Jonas, Melanie

AU - Rothwell, John C

AU - Siebner, Hartwig R

AU - Münchau, Alexander

N1 - © 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

PY - 2010/11/1

Y1 - 2010/11/1

N2 - In 19 healthy volunteers, we used transcranial magnetic stimulation (TMS) to probe the excitability in pathways linking the left dorsal premotor cortex and right primary motor cortex and those linking the left and right motor cortex during the response delay and the reaction time period while subjects performed a delayed response [symbol 1 (S1) - symbol 2 (S2)] Go-NoGo reaction time task with visual cues. Conditioning TMS pulses were applied to the left premotor or left motor cortex 8 ms before a test pulse was given to the right motor cortex at 300 or 1800 ms after S1 or 150 ms after S2. S1 coded for right-hand or left-hand movement, and S2 for release or stopping the prepared movement. Conditioning of the left premotor cortex led to interhemispheric inhibition at 300 ms post-S1, interhemispheric facilitation at 150 ms post-S2, and shorter reaction times in the move-left condition. Conditioning of the left motor cortex led to inhibition at 1800 ms post-S1 and 150 ms post-S2, and slower reaction times for move-right conditions, and inhibition at 300 and 1800 ms post-S1 for move-left conditions. Relative motor evoked potential amplitudes following premotor conditioning at 150 ms post-S2 were significantly smaller in 'NoGo' than in 'Go' trials for move-left instructions. We conclude that the excitability in left premotor/motor right motor pathways is context-dependent and affects motor behaviour. Thus, the left premotor cortex is engaged not only in action selection but also in withholding and releasing a preselected movement generated by the right motor cortex.

AB - In 19 healthy volunteers, we used transcranial magnetic stimulation (TMS) to probe the excitability in pathways linking the left dorsal premotor cortex and right primary motor cortex and those linking the left and right motor cortex during the response delay and the reaction time period while subjects performed a delayed response [symbol 1 (S1) - symbol 2 (S2)] Go-NoGo reaction time task with visual cues. Conditioning TMS pulses were applied to the left premotor or left motor cortex 8 ms before a test pulse was given to the right motor cortex at 300 or 1800 ms after S1 or 150 ms after S2. S1 coded for right-hand or left-hand movement, and S2 for release or stopping the prepared movement. Conditioning of the left premotor cortex led to interhemispheric inhibition at 300 ms post-S1, interhemispheric facilitation at 150 ms post-S2, and shorter reaction times in the move-left condition. Conditioning of the left motor cortex led to inhibition at 1800 ms post-S1 and 150 ms post-S2, and slower reaction times for move-right conditions, and inhibition at 300 and 1800 ms post-S1 for move-left conditions. Relative motor evoked potential amplitudes following premotor conditioning at 150 ms post-S2 were significantly smaller in 'NoGo' than in 'Go' trials for move-left instructions. We conclude that the excitability in left premotor/motor right motor pathways is context-dependent and affects motor behaviour. Thus, the left premotor cortex is engaged not only in action selection but also in withholding and releasing a preselected movement generated by the right motor cortex.

KW - Adult

KW - Brain Mapping

KW - Evoked Potentials, Motor

KW - Female

KW - Functional Laterality

KW - Hand

KW - Humans

KW - Male

KW - Motor Activity

KW - Motor Cortex

KW - Movement

KW - Neural Pathways

KW - Psychomotor Performance

KW - Transcranial Magnetic Stimulation

U2 - 10.1111/j.1460-9568.2010.07442.x

DO - 10.1111/j.1460-9568.2010.07442.x

M3 - Journal article

C2 - 21059111

VL - 32

SP - 1771

EP - 1779

JO - European Journal of Neuroscience

JF - European Journal of Neuroscience

SN - 0953-816X

IS - 10

ER -