TY - JOUR
T1 - Neural correlates of auditory stream segregation in primary auditory cortex of the awake monkey
AU - Fishman, Yonatan I.
AU - Reser, David H.
AU - Arezzo, Joseph C.
AU - Steinschneider, Mitchell
N1 - Funding Information:
This research was supported by grants DC00657 and HD01799, and the Institute for the Study of Music and Neurologic Function of Beth Abraham Hospital. We are grateful to Dr. Steven Walkley, May Huang, Linda O’Donnell, Shirley Seto and Dr. Elena Zotova for providing excellent technical, secretarial and histological assistance.
PY - 2001
Y1 - 2001
N2 - An important feature of auditory scene analysis is the perceptual organization of sequential sound components, or 'auditory stream segregation'. Auditory stream segregation can be demonstrated by presenting a sequence of high and low frequency tones in an alternating pattern, ABAB. When the tone presentation rate (PR) is slow or the frequency separation (ΔF) between the tones is small (<10%), a connected alternating sequence ABAB is perceived. When the PR is fast or the ΔF is large, however, the alternating sequence perceptually splits into two parallel auditory streams, one composed of interrupted 'A' tones, and the other of interrupted 'B' tones. The neurophysiological basis of this perceptual phenomenon is unknown. Neural correlates of auditory stream segregation were examined in A1 of the awake monkey using neuronal ensemble techniques (multiunit activity and current source density). Responses evoked by alternating frequency sequences of tones, ABAB, were studied as a function of PR (5, 10, 20 and 40 Hz). 'A' tones corresponded to the best frequency (BF) of the cortical site, while 'B' tones were situated away from the BF by an amount ΔF. At slow PRs, 'A' and 'B' tones evoked responses that generated an overall pattern of activity at the stimulus PR. In contrast, at fast PRs, 'B' tone responses were differentially suppressed, resulting in a pattern of activity consisting predominantly of 'A' tone responses at half the PR. The magnitude of 'B' tone response suppression increased with ΔF. Differential suppression of BF and non-BF tone responses at high PRs can be explained by physiological principles of forward masking. The effect of ΔF is explained by the hypothesis that responses to tones distant from the BF are more susceptible to suppression by BF tones than responses to tones near the BF. These results parallel human psychoacoustics of auditory stream segregation and suggest a cortical basis for the perceptual phenomenon. Copyright (C) 2001 Elsevier Science B.V.
AB - An important feature of auditory scene analysis is the perceptual organization of sequential sound components, or 'auditory stream segregation'. Auditory stream segregation can be demonstrated by presenting a sequence of high and low frequency tones in an alternating pattern, ABAB. When the tone presentation rate (PR) is slow or the frequency separation (ΔF) between the tones is small (<10%), a connected alternating sequence ABAB is perceived. When the PR is fast or the ΔF is large, however, the alternating sequence perceptually splits into two parallel auditory streams, one composed of interrupted 'A' tones, and the other of interrupted 'B' tones. The neurophysiological basis of this perceptual phenomenon is unknown. Neural correlates of auditory stream segregation were examined in A1 of the awake monkey using neuronal ensemble techniques (multiunit activity and current source density). Responses evoked by alternating frequency sequences of tones, ABAB, were studied as a function of PR (5, 10, 20 and 40 Hz). 'A' tones corresponded to the best frequency (BF) of the cortical site, while 'B' tones were situated away from the BF by an amount ΔF. At slow PRs, 'A' and 'B' tones evoked responses that generated an overall pattern of activity at the stimulus PR. In contrast, at fast PRs, 'B' tone responses were differentially suppressed, resulting in a pattern of activity consisting predominantly of 'A' tone responses at half the PR. The magnitude of 'B' tone response suppression increased with ΔF. Differential suppression of BF and non-BF tone responses at high PRs can be explained by physiological principles of forward masking. The effect of ΔF is explained by the hypothesis that responses to tones distant from the BF are more susceptible to suppression by BF tones than responses to tones near the BF. These results parallel human psychoacoustics of auditory stream segregation and suggest a cortical basis for the perceptual phenomenon. Copyright (C) 2001 Elsevier Science B.V.
KW - Auditory cortex
KW - Current source density
KW - Monkey
KW - Multiunit activity
KW - Stream segregation
UR - http://www.scopus.com/inward/record.url?scp=0035208427&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035208427&partnerID=8YFLogxK
U2 - 10.1016/S0378-5955(00)00224-0
DO - 10.1016/S0378-5955(00)00224-0
M3 - Article
C2 - 11124464
AN - SCOPUS:0035208427
SN - 0378-5955
VL - 151
SP - 167
EP - 187
JO - Hearing Research
JF - Hearing Research
IS - 1-2
ER -