Frame-Up. Focus on “Eye-Centered, Head-Centered, and Complex Coding of Visual and Auditory Targets in the Intraparietal Sulcus”

Abstract

As neuroscientists, the world would be simpler if the frame of reference for spatial information in the brain reflected either the sensory apparatus from which the signals were derived or the motor apparatus toward which the signals were aimed. In this simple world, the neural correlate of a visual stimulus would reflect where on the retina the stimulus had appeared, while the neural correlate of an auditory stimulus would reflect where the sound source was relative to the ears. An area involved in coding arm movements would reflect the goal location relative to current arm position. Unfortunately, the world is not so simple. In this issue of the Journal of Neurophysiology (p. 2331–2352), Mullette-Gillman and colleagues (2005), recording from neurons on both banks of the intraparietal sulcus (IPS), show that individual neurons represent the spatial locations of visual and auditory stimuli similarly and that many neurons use idiosyncratic frames of reference that are neither head-centered nor eye-centered. Similar findings were just reported by Schlack and colleagues (2005) in the IPS fundus. These findings are part of a shift toward a new view of frames of reference in the brain.