The effects of upper and lower limb movements accompanying the speech on motor readiness potential

Contingent Negative Variation (CNV), a slow negative cortical potential as one of the types of event-related potentials is a motor cortical preparation occuring during the cortical motor preparation before the voluntary motor movement. It has been known that the CNVs occuring before upper and lower limb movements have different topographic distributions. In spite of the fact that, there is a cerebral distance between the upper and lower movement systems, it was confirmed that there was an increase in neural interaction during the preparation and movement stages of simultaneous movement. In addition to the interaction between the upper and lower extremities, speech-related motor components are also in interaction with distal extremities. It was found that contraction of the oral muscles causes a facilitatory effect on the extremities. This study was conducted in accordance with the experimental paradigm of CNV, and the largest slope and related time windows values in frontal and central areas before extremities movements accompanying speech were analyzed by repeated measures analysis of variance in terms of the factors of condition, channel and condition * channel. We have collected 19-channel electroencephalography from 24 healthy subjects in this study. The statistical analysis of frontal and central slope values showed a significant difference in different conditions. The conditions between foot-hand and hand-speech show statistically significant differences. The dependency of the largest slope for each condition and related time windows were found statistically significant. This study determined how the simultaneous movements affect the motor preparation stage of the speech and it may provide a unique contribution to the studies related to speech rehabilitation. Key Words: Accompanying motor movements, Event-related Potentials, Contingent Negative Variation, Speech, Upper and Lower Limb Movement