Inhibition effects of fNIRS signals of prefrontal cortex by low-passed dynamic random-dot patterns

Abstract

In the measurement techniques of cortical activity by using the functional near-infrared spectroscopy (fNIRS), the differences between resting state and task-performing state is often evaluated. However, the experimental conditions of resting state are not controlled. In this study, we investigated the effects of the low-passed dynamic random-dot patterns (LPDRDs) on the resting-state activities. We measured fNIRS signals from prefrontal cortex (PFC) and right-lateral temporal cortex (rLTC) during a block design paradigms, which is constructed of resting-state block with a LPDRD or a fixation crosshair (FT) after performing a 3-back task. We compared which condition is to be recovered to resting-state earlier after brain activation by the task. The results suggest that the average activity of PFC in the LPDRD condition was significantly lower than in the FT condition, indicating that gazing at the LPDRD in resting-state could be attenuated cortical activity more efficiently.