Hearing in a “Moving” Visual World: Coordinate Transformations Along the Auditory Pathway

This chapter reviews the literature on how auditory signals are transformed into a coordinate system that facilitates interactions with the visual system. Sound location is deduced from cues that depend on the position of the sound with respect to the head, but visual location is deduced from the pattern of light illuminating the retina, yielding an eye-centered code. Connecting sights and sounds originating from the same position in the physical world requires the brain to incorporate information about the position of the eyes with respect to the head. Eye position has been found to interact with auditory signals at all levels of the auditory pathway that have been tested but usually yields a code that is in a hybrid reference frame: neither head nor eye centered. Computing a coordinate transformation, in principle, may be easy, which could suggest that the looseness of the computational constraints may permit hybrid coding. A review of the behavioral literature addressing the effects of eye gaze on auditory spatial perception and a discussion of its consistency with physiological observations concludes the chapter.