Hearing speech against spatially separate competing speech versus competing noise

Abstract

Listeners had the task of following a target speech signal heard against two competitors either located at the same spatial position as the target or displaced symmetrically to locations flanking it. When speech was the competitor, there was a significantly higher separation effect (maintained intelligibility with reduced target sound level), as compared with either steady-state or fluctuating noises. Increasing the extent of spatial separation slightly increased the effect, and a substantial contribution of interaural time differences was observed. When same-and opposite-sex voices were used, a hypothesis that the similarity between target and competing speech would explain the role for spatial separation was partly supported. High-and low-pass filtering showed that both parts of an acoustically similar competing signal contribute to the phenomenon. We conclude that, in parsing the auditory array, attention to spatial cues is heightened when the components of the array are confusable on other acoustic grounds.

Binaural Glimpses at the Cocktail Party?

“…This reduction in SRM for SSN maskers is in line with experimental data from other studies comparing SRM with speech or speech-like maskers (e.g. Jones and Litovsky 2011;Noble and Perrett 2002). Comparisons with all less complex BSIM versions (coloured bars) demonstrate that the SRM in such spatial masker configurations is dominated by the EC stage.…”

“…spatial release from masking (SRM), between 5 and 12 dB depending on the spatial separation of target and masker (e.g. Marrone et al 2008;Noble and Perrett 2002). One potential mechanism underlying SRM in these conditions is the binaural processing of the interaural level difference (ILD) and interaural time difference (ITD) as, e.g.…”

Speech intelligibility reduces over distance from an attended location: Evidence for an auditory spatial gradient of attention

“…Both values are also lower than the 4.5-dB unmasking found by Noble and Perrett (2002) for a symmetrical spatial separation of 30º with a female target and two maskers. Same-gender target and maskers tend to produce high levels of information masking (Brungart, 2001) and consequently larger spatial release from masking (e.g., Brungart, 2001;Brungart et al, 2001;Festen & Plomp, 1990;Freyman et al, 2001;Hall, Buss, & Grose, 2005;Kidd et al, 1998;Noble & Perrett, 2002;Rhebergen, Versfeld, & Dreschler, 2005). Using the same talker for target and maskers in this study maximized informational masking while maintaining considerable energetic masking because of identical voice characteristics.…”

“…Numerous studies have demonstrated that spatially separating a target and masker leads to a release from masking, as measured by improved target discrimination (e.g., Freyman, Balakrishnan, & Helfer, 2001;Kidd, Mason, Deliwala, Woods, & Colburn, 1994;Kidd, Mason, Rohtla, & Deliwala, 1998;Litovsky, 2005;Noble & Perrett, 2002). Two types of masking have been recognized in this context: energetic masking and informational masking.…”

“…Indeed, when interferers are the same gender as the target, rendering voice characteristic cues less salient, spatial separation of masker and target is more beneficial than when large differences in voice characteristics occur between talkers (e.g., Festen & Plomp, 1990;Noble & Perrett, 2002). Using tones, Mondor, Zatorre, and Terrio (1998) showed that location and frequency could not be independently attended to when strong cues were available for each, even though location cues were irrelevant to the experimental task.…”