SOUND ORIENTATION BEHAVIOR IN CATS .1. LOCALIZATION OF BROAD-BAND NOISE

Behavioral experiments measured the accuracy of the cat's voluntary he ad orientation responses to bursts of broadband noise at 104 locations in the frontal sound field. Cats were presented sound stimuli at rand omly selected locations and received a food reward for releasing a lev er when a Light-emitting diode (LED) flashed at the same location. Hea d movements to the perceived location of the acoustic stimulus, and th erefore expected location of the LED cue, were tracked by an electroma gnetic sensor. Orientation responses to single sound bursts were direc ted to within 5 degrees of the azimuth and elevation of sounds within 15 degrees of the immediate frontal field and did not change for burst durations of 40, 100, and 200 ms. An increasing underestimation of ta rget location was observed as the sound stimulus moved to more lateral azimuths and higher elevations. The ''undershoot'' phenomenon was red uced by allowing subjects to track paired stimulus bursts that repeate d from the same location. These effects of sound location on the accur acy of orientation responses are predicted by the availability of mid- frequency spectral cues for sound localization. (C) 1996 Acoustical So ciety of America.