Abstract
A growing body of literature shows that perceived duration decreases with increasing eccentricity. Studies demonstrating this effect required participants to constantly fixate on a central fixation cross during stimulus presentation. Hence, saccadic eye movements elicited by peripheral stimuli had to be inhibited. Performing saccadic eye movements during stimulus presentation is known to distort perceived duration. A further study could demonstrate that the perceived timing of a stimulus that triggers the programming or execution of a saccadic eye movement is distorted compared to a stimulus that is merely observed passively. The aim of the present study is to investigate the perceived duration of a peripheral stimulus when a saccade towards its position is either executed or inhibited. In a temporal bisection task N = 21 participants categorized a black disc as either short or long. The duration of the disc varied from 20-220 ms and was presented in 6° or 12° of eccentricity on the horizontal meridian. Further, subjects were instructed to keep their gaze fixated on a central fixation cross or to perform a saccade towards the peripheral stimulus position in a block-wise manner. Block order was counterbalanced between participants. We replicated the effect of eccentricity on perceived duration: Stimuli presented at 12° of eccentricity were underestimated compared to stimuli presented at 6°. Saccade inhibition versus saccade execution did not affect duration estimates differentially, except when taking block order into account: Descriptively, the effect was larger in the saccade condition when the saccade condition was performed second. There was no effect of block order when the saccade condition was performed first. Results are discussed in the context of reference effects.