Perisaccadic localization of auditory stimuli.

Interaction with the outside world requires the knowledge about where objects are with respect to one's own body. Such spatial information is represented in various topographic maps in different sensory systems. From a computational point of view, however, a single, modality-invariant map of the incoming sensory signals appears to be a more efficient strategy for spatial representations. If such a single supra-modal map existed and were used for perceptual purposes, localization characteristics should be similar across modalities. Previous studies had shown mislocalization of brief visual stimuli presented in the temporal vicinity of saccadic eye-movements. Here, we tested, if such mislocalizations could also be found for auditory stimuli. We presented brief noise bursts before, during, and after visually guided saccades. Indeed, we found localization errors for these auditory stimuli. The spatio-temporal pattern of this mislocalization, however, clearly differed from the one found for visual stimuli. The spatial error also depended on the exact type of eye-movement (visually guided vs. memory guided saccades). Finally, results obtained in fixational control paradigms under different conditions suggest that auditory localization can be strongly influenced by both static and dynamic visual stimuli. Visual localization on the other hand is not influenced by distracting visual stimuli but can be inaccurate in the temporal vicinity of eye-movements. Taken together, our results argue against a single, modality-independent spatial representation of sensory signals.