Inhibition of return revisited: Localized inhibition on top of a pervasive bias.

An inhibitory after-effect of attention, frequently referred to as inhibition of return (IOR), operates at a previously attended location to discourage perseverative orienting. Using the classic cueing task, previous work has shown that IOR is not restricted to a previously attended location, but rather spreads to adjacent visual space in a graded manner. The present study expands on this earlier work by exploring a wider visual region and a broader range of cue-target onset asynchronies (CTOAs) to characterize the temporal dynamics of the IOR gradient. The results reveal that the magnitude of IOR generated by cueing decreases exponentially as the CTOA increases. The width of the IOR gradient first increases and then decreases, with a temporal profile that is well captured by an alpha function. Importantly, the present study reveals that in addition to its rapidly decaying local properties, cue-induced IOR can include a pervasive inhibitory bias, which remains relatively stable across IOR's lifetime.