Long-latency TMS-evoked potentials during motor execution and inhibition

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Motor Control

Background:

• Transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG) reveals cortical reactivity and connectivity.
• Understanding the neural patterns associated with motor response inhibition is crucial but remains unclear.

Purpose of the Study:

• To investigate the spatio-temporal patterns of TMS-evoked potentials (TEPs) during motor execution and inhibition.
• To elucidate the role of cortical plasticity in response inhibition using TMS-EEG.

Main Methods:

• Participants performed a go/stop task while undergoing TMS-EEG recording.
• Single-pulse TMS was applied to the motor cortex during go and stop trials.
• TEPs were analyzed by comparing EEG waveforms with and without TMS.

Main Results:

• A prominent negative deflection (N100) and a later positive component (LPC) were observed in TEPs.
• N100 and LPC amplitudes were modulated differently in go versus stop trials when TMS was applied just before the target time.
• LPC amplitude decreased and latency was delayed in both go and stop trials under specific TMS timing conditions.

Conclusions:

• TMS-induced neuronal activity in the motor cortex changes functionally based on task demands during motor execution and inhibition.
• Cortical plasticity plays a significant role in the dynamic modulation of neural responses during motor control and response inhibition.