Beta band patterns in the visible and masked sections of the coincidence-anticipation timing task.

In this study, we examined beta band patterns during the coincidence-anticipation timing task. The tasks were the coincidence-anticipation timing task using a partially masked stimulus runway and a control task using the stimulus runway with no masking. Both tasks were displayed on a computer screen placed 1.3 m in front of the participants while they were seated in an armchair. Ten healthy right-handed adult men were asked to press a holding push button with their right thumb when a downward-moving visual target arrived at the end of each task. The electroencephalogram during both tasks was divided into three segments: the visible section, the first half of the masked section, and the second half of the masked section. The valid epochs were subjected to fast Fourier transform to obtain the power density in the beta bands. Power in the beta bands was expressed as a percentage of the total power (3-30 Hz) in each segment. The results showed that the percentage of beta band activity in Brodmann's areas 7 and 19 was significantly increased in both the visible and the masked sections of the coincidence-anticipation timing task compared with the control task. These results suggest that Brodmann's areas 7 and 19 mainly contribute toward attention to visual targets in the visible section and to movement prediction of moving visual targets in the masked section. In addition, Brodmann's areas 9 and 10, which were inactive, might affect the response time in the masked section during the coincidence-anticipation timing task.