Figure 1.

Setup for auditory spatio-temporal bisection. For each trial, subjects listened to a sequence of 3 sounds in the lower visual hemifield (S1, S2, S3) that lasted 1.5 sec with S1 and S3 at fixed position of ±25° with respect to the subject midline. S2 could occur randomly and independently at ±4.5° (a) and ±250 ms (b) from the physical spatial and temporal mid points (dashed vertical line). To avoid stereotypical subject responses, S2 was also presented at 0° and at 0 ms during catch trials. Subjects were instructed to judge whether the position of S2 in space or in time (two separate blocks) is farther from S1 or S3 (bisection task).