Study of cerebral cortico-cortical coherence during motor practice

Abstract

BACKGROUND: Coherence is one of the neural mechanisms related to communication and plasticity. The literature presents two divergent results regarding coherence and motor practice. One result suggests a decrease in coherence during practice, while the other indicatesan increase in coherence throughout practice. AIM: Considering these two divergent results in the literature, this study aimed to examine the role of coherence in motor practice. We hypothesize that electrode pairs related to C3 (C3-P3and C3-F3) show an increase of coherence during practice, while electrodes less related to motor action (F4, C4, and P4) may exhibit decreased. METHOD: Twenty-four right-handed participants practice 120 trials of a sequential key-pressing task. RESULTS:The results indicated, in the alpha upper and theta bands, from initiation to end of practice, the coherence increased in the F3-C3 electrode pair and decreased in the C3-C4, C3-P3, P3-P4, F3-P3, and C4-P4 electrodes pairs. CONCLUSION: The results partially confirmed the hypothesis. The coherence increases in the electrode pairings related to the motor execution and decreases between the lesser related. During the motor learning process, communication reduction occurred in groups of neurons not associatedwith the stimulus, and the potentiation of synaptic plasticity within groups of neurons associated with the stimulus occurred.