Contributions of talker characteristics and spatial location to auditory streaming

Abstract

To examine whether auditory streaming contributes to unmasking, intelligibility of target sentences against two competing talkers was measured using the coordinate response measure (CRM) [Bolia et al., J. Acoust. Soc. Am. 107, 1065-1066 (2007)] corpus. In the control condition, the speech reception threshold (50% correct) was measured when the target and two maskers were collocated straight ahead. Separating maskers from the target by +/-30 degrees resulted in spatial release from masking of 12 dB. CRM sentences involve an identifier in the first part and two target words in the second part. In experimental conditions, masking talkers started spatially separated at +/-30 degrees but became collocated with the target before the scoring words. In one experiment, one target and two different maskers were randomly selected from a mixed-sex corpus. Significant unmasking of 4 dB remained despite the absence of persistent location cues. When same-sex talkers were used as maskers and target, unmasking was reduced. These data suggest that initial separation may permit confident identification and streaming of the target and masker speech where significant differences between target and masker voice characteristics exist, but where target and masker characteristics are similar, listeners must rely more heavily on continuing spatial cues.

Effect of fundamental-frequency and sentence-onset differences on speech-identification performance of young and older adults in a competing-talker background

“…Results from COLEA analysis showed that the mean F0 value was 115.8 Hz ranging from 101.7 to 147.9 Hz (SD ¼ 6.4 Hz). This value was comparable to the mean F0 value of T1 of 118.3 Hz estimated for these same materials and talker by Allen et al (2008) using Kay Elemetrics Computerized Speech Lab version 4500.…”

Disentangling the effects of spatial cues on selection and formation of auditory objects

“…This spatial effect does not require spatially directed attention ͑Edmonds and Culling, 2005a;Edmonds and Culling, 2005b;Culling et al, 2006;Allen et al, 2008͒ and appears to operate primarily by making it possible to detect near-threshold portions of the target ͑Shinn- Cunningham, 2005;Zurek, 1993͒. Many studies point out that spatial cues carry little weight in enabling the segregation of sound locally in time at the level of syllables ͑Kubovy, 1981; Culling and Summerfield, 1995a;Darwin and Hukin, 1997;ShinnCunningham et al, 2007͒. While spatial cues provide little aid in segregating sources at a local time scale, spatial separation of competing sources improves the ability to selectively attend to a target when target location is the main cue differentiating the target from the other sources in the mixture ͑Freyman et Gallun et al, 2005;ShinnCunningham et al, 2005a;Ihlefeld and Shinn-Cunningham, 2008͒.…”

Problems Hearing in Noise in Older Adults

“…First, if we were to attempt to compare these results with the 10.7 dB to 12.8 dB of benefit reported in normalhearers by Allen et al (2008), then the assumption could be made that the spatial processing ability of the older adults is reduced. However, this would be an inappropriate comparison to make as the studies use different protocols including a different target stimulus and distracting noise.…”

“…The role of spatial processing ability in teasing apart competing messages has been acknowledged since the groundbreaking article from Cherry (1953). Spatial processing is 1 usually calculated in research studies as the difference in scores obtained on two test conditions of a speech reception in noise task, where the only difference between conditions is whether there is spatial separation between where the target speech originates and where the noise originates (Ahlstrom, Horwitz, & Dubno, 2009;Allen, Carlile, & Alais, 2008;Arbogast, Mason, & Kidd, 2005;Brown, Cameron, Martin, Watson, & Dillon., 2010;Cameron & Dillon, 2007;Cameron & Dillon, 2009;Dubno et al, 2002;Dubno, Ahlstrom, & Horwitz, 2008;Gelfand, Ross, & Miller, 1988;Kim, Frisina, & Frisina, 2006). Spatial processing ability has been referred to in the literature by a number of terms over the years, including, but not limited to, spatial release from masking, spatial hearing, spatial stream segregation, spatial advantage, and in limited contexts binaural advantage.…”