TY - JOUR
T1 - Auditory localization of nearby sources. III. Stimulus effects
AU - Brungart, Douglas S.
PY - 1999
Y1 - 1999
N2 - A series of experiments has examined the auditory localization of a nearby (< 1 m) sound source under four conditions: (1) a fixed-amplitude condition where loudness-based distance cues were available; (2) a monaural condition where the contralateral ear was occluded by an ear-plug and muff; (3) a high-pass condition where the stimulus bandwidth was 3 Hz to 15 kHz; and (4) a low-pass condition where the stimulus bandwidth was 200 Hz to 3 kHz. The results of these experiments were compared to those of a previous experiment that measured localization performance for a nearby broadband, random-amplitude source [Brungart et al., J. Acoust. Soc. Am. 106, 1956-1968 (1999)]. Directional localization performance in each condition was consistent with the results of previous far-field localization experiments. Distance localization accuracy improved slightly in the fixed-amplitude condition relative to the earlier broadband random-amplitude experiment, especially near the median plane, but was severely degraded in the monaural condition. Distance accuracy was also found to be highly dependent on the low-frequency energy of the stimulus: in the low-pass condition, distance accuracy was similar to that in the broadband condition, while in the high- pass condition, distance accuracy was significantly reduced. The results suggest that low-frequency interaural level differences are the dominant auditory distance cue in the proximal region.
AB - A series of experiments has examined the auditory localization of a nearby (< 1 m) sound source under four conditions: (1) a fixed-amplitude condition where loudness-based distance cues were available; (2) a monaural condition where the contralateral ear was occluded by an ear-plug and muff; (3) a high-pass condition where the stimulus bandwidth was 3 Hz to 15 kHz; and (4) a low-pass condition where the stimulus bandwidth was 200 Hz to 3 kHz. The results of these experiments were compared to those of a previous experiment that measured localization performance for a nearby broadband, random-amplitude source [Brungart et al., J. Acoust. Soc. Am. 106, 1956-1968 (1999)]. Directional localization performance in each condition was consistent with the results of previous far-field localization experiments. Distance localization accuracy improved slightly in the fixed-amplitude condition relative to the earlier broadband random-amplitude experiment, especially near the median plane, but was severely degraded in the monaural condition. Distance accuracy was also found to be highly dependent on the low-frequency energy of the stimulus: in the low-pass condition, distance accuracy was similar to that in the broadband condition, while in the high- pass condition, distance accuracy was significantly reduced. The results suggest that low-frequency interaural level differences are the dominant auditory distance cue in the proximal region.
UR - http://www.scopus.com/inward/record.url?scp=0032803351&partnerID=8YFLogxK
U2 - 10.1121/1.428212
DO - 10.1121/1.428212
M3 - Article
C2 - 10615699
AN - SCOPUS:0032803351
SN - 0001-4966
VL - 106
SP - 3589
EP - 3602
JO - Journal of the Acoustical Society of America
JF - Journal of the Acoustical Society of America
IS - 6
ER -