Maintenance of Inhibitory Bias in Premotor Cortex during Spatial Inhibition of Return

摘要

Introduction: Exogenous orienting of attention typically produces a later inhibitory effect (inhibition of return; IOR) in response to the target. In order for IOR to occur, attention has to be first disengaged from the cued location and an inhibitory bias is then built up and maintained until the appearance of the target. Neural correlates of the maintenance of inhibitory bias remains unclear since this maintenance process cannot be separated out in the single-cue paradigm. In this fMRI study, we adopted a double-cue paradigm in which a second central cue was introduced to reflexively attract attention away from the cued location so that the maintenance process can be separated from the previous disengagement process. By parametrically varying the time interval between the central cue and the target, we aimed to investigate the neural correlates of the maintenance of inhibitory bias during spatial IOR.