Effects of brain network segregation and integration on motor imagery sensorimotor rhythm

Abstract

Diverse cognitive processes place different demands on locally segregated and globally integrated brain activities. Motor imagery (MI) is a complex mental operation characterized by sensorimotor rhythms. However, how the brain network acts on MI rhythms is not well-known. The present work aimed to explore the effects of brain integration and segregation on brain rhythmic oscillations. The power spectrum dynamics, topography distribution, and brain network metrics in the alpha and beta bands were calculated. And the correlations were investigated with the network metrics and sensorimotor rhythm. The results showed that the degree of event-related desynchronization/synchronization (ERD/ERS) was higher in alpha band than in beta band during [−1, 1 s] (p < 0.01). The topography of the alpha band demonstrated a bilateral distribution during MI processing, while the beta band had more diffuse distributions around the centre. Moreover, global efficiency was associated with bilateral ERD, and the transitivity was related to contralateral local power. These results suggested that network functions could facilitate the completion of behavior tasks. The integration was related to bilateral hemisphere coordination and the segregation was related to local activation, which shaped the local neural modulation of individuals in MI.

Keywords

• motor imagery
• segregation
• integration
• sensorimotor rhythm