The Role of Auditory Cortex in Spatial Processing

One of the primary functions of the sensory nervous system is to determine and represent where stimuli originate from. This is critical for identifying predators and prey, as well as mate selection and attending objects of interest. Audition is one of the three primary senses that can provide some information about extrapersonal space, together with vision and olfaction. The latter two sensory systems de fi ne the range of spatial localization abilities, with olfactory spatial perception being extremely poor under most naturalistic conditions (Doty, 2001 ; Kauer & White, 2001 ) , and visual spatial perception being very accurate (Westheimer, 1984 ; Shapley & Lennie, 1985 ) . Auditory spatial perception is somewhere in between (Blauert, 1997 ) , but holds a signi fi cant advantage over vision in that it is sensitive to all regions of extrapersonal space, not just the visual fi eld, which is restricted to frontal space in most primates. As well as being ethologically vital in terrestrial mammals, a second consideration of auditory spatial perception is that it is necessarily computed by the nervous system. This is because, unlike the visual system, the sensory epithelium cannot encode acoustic spatial location. Neural computations are not restricted to the perception of acoustic space, of course, as any but the simplest percepts are dependent on the nervous system computing and extracting particular stimulus features (see Schnupp, Honey, and Willmore, Chapter 5 ; Poremba and Bigelow, Chapter 6 ;