In Brief:
Twenty-two postlingually deafened adults, bilaterally fitted with cochlear implants, were tested in a localization task employing a loudspeaker array spanning azimuths ±90°. The initial test, employing brief speech or noise signals, occurred 5 mo after implant activation. Listening bilaterally, subjects could localize both signals at a much better than chance level. Furthermore, localization error was significantly smaller for the speech than for the noise signal. Twelve of the subjects were retested 10 mo after their first test. Average performance for the second test was not different from that for the first test, although two subjects who performed poorly during their first visit showed substantial improvement on their second visit. A second experiment indicated that interaural level difference cues were the basis for localization ability, and that interaural temporal difference cues did not contribute.
