M N McDonnell1, M C Ridding. 1. Research Centre for Human Movement Control, School of Molecular and Biomedical Science, The University of Adelaide, Adelaide, SA 5005, Australia.
Abstract
OBJECTIVE: To investigate the mechanism involved in the transient suppression of the response to transcranial magnetic stimulation (TMS) following repeated performance of a complex sensorimotor training task (ST). METHODS: A total of 19 healthy subjects participated in 4 experiments, all involving performance of the grooved pegboard test (GPT). The experiments investigated the effect of the ST on corticospinal and intracortical excitability, spinal excitability and maximal pinch grip force. RESULTS: Motor evoked potential amplitude decreased significantly following the ST in both muscles tested and this was associated, but not correlated, with a decrease in the time taken to perform the GPT. There was no change in intracortical inhibition or facilitation (tested at interstimulus intervals of 3 and 10 ms, respectively). M wave amplitude was unchanged, as were F wave amplitude, latency and persistence and there was no evidence of muscle fatigue. CONCLUSIONS: The reduction in corticospinal excitability was short lasting (<10 min) and was not accompanied by changes at the spinal or peripheral level, suggesting that other intracortical circuits may be involved. SIGNIFICANCE: Repeated performance of motor tasks can result in both short- and long-term modulation of motor cortical excitability. However, the relationship between changes in corticospinal excitability and motor performance is complex and critically dependent upon task type and duration.
OBJECTIVE: To investigate the mechanism involved in the transient suppression of the response to transcranial magnetic stimulation (TMS) following repeated performance of a complex sensorimotor training task (ST). METHODS: A total of 19 healthy subjects participated in 4 experiments, all involving performance of the grooved pegboard test (GPT). The experiments investigated the effect of the ST on corticospinal and intracortical excitability, spinal excitability and maximal pinch grip force. RESULTS: Motor evoked potential amplitude decreased significantly following the ST in both muscles tested and this was associated, but not correlated, with a decrease in the time taken to perform the GPT. There was no change in intracortical inhibition or facilitation (tested at interstimulus intervals of 3 and 10 ms, respectively). M wave amplitude was unchanged, as were F wave amplitude, latency and persistence and there was no evidence of muscle fatigue. CONCLUSIONS: The reduction in corticospinal excitability was short lasting (<10 min) and was not accompanied by changes at the spinal or peripheral level, suggesting that other intracortical circuits may be involved. SIGNIFICANCE: Repeated performance of motor tasks can result in both short- and long-term modulation of motor cortical excitability. However, the relationship between changes in corticospinal excitability and motor performance is complex and critically dependent upon task type and duration.
Authors: Adjmal M E Sarwary; Miles Wischnewski; Dennis J L G Schutter; Luc P J Selen; W Pieter Medendorp Journal: J Neurophysiol Date: 2018-08-22 Impact factor: 2.714
Authors: Janine Reis; Orlando B Swayne; Yves Vandermeeren; Mickael Camus; Michael A Dimyan; Michelle Harris-Love; Monica A Perez; Patrick Ragert; John C Rothwell; Leonardo G Cohen Journal: J Physiol Date: 2007-11-01 Impact factor: 5.182