Multisensory stimuli improve relative localisation judgments compared to unisensory auditory or visual stimuli

Observers performed a relative localisation task in which they reported whether the second of two sequentially presented signals occurred to the left or right of the first. Stimuli were detectability-matched auditory, visual, or auditory-visual signals and the goal was to compare changes in performance with eccentricity across modalities. Visual performance was superior to auditory at the midline, but inferior in the periphery, while auditory-visual performance exceeded both at all locations. No such advantage was seen when performance for auditory-only trials was contrasted with trials in which the first stimulus was auditory-visual and the second auditory only.