Análise do eletroencefalograma durante estimulação visual por realidade virtual estereoscópica em tarefa de interceptação de bola

Abstract

This Thesis developed a voluntary movement evaluation protocol, composed by a ball interception task, in a stereoscopic virtual reality environment. Thirty one righthanded volunteers participated of the experimental protocol, that simulated the point of view of goal keeper during soccer penalty defense, with three types of random stimuli, 28 each: left, centered and right ball. Two segments of EEG signals were studied in order to observe the expectancy-related potential (CNV). (1) 2 s before the beginning of the movement detected by the accelerometer and (2) 4 s between the sound of the whistle and the beginning of the movement of the ball. The epochs composed by the segment (2), present a higher CNV (p < 0.001) when compared to the segments (1). The ERD/ERS index was applied to 28 pairs of epochs of 0.5 s each, and indicates a consistent occurrence of ERS in the gamma band, but not for alpha and beta bands, and additionally, the occurrence of synchronization seems to differ related to ball direction. The EEG complexity was analyzed, indicating that the effect of ball direction was not detected by the response time (TMR – p > 0.05), but by the cortical responses (p < 0.05), and only after the ball initiate your trajectory (p < 0.001). Therefore, it seems that the ball direction influence the complexity of cortical responses after the beginning of the ball’s motion. Forma adicional Também disponível on-line.