Talker head-orientation and extended high-frequency benefits for speech recognition as a function of masker head angle

<jats:p>Several types of cues contribute to speech recognition in multi-talker environments. In this study, we investigated how talker head-orientation related (THOR) cues and extended high-frequency (EHF; &gt;8kHz) cues affect speech-in-speech recognition for both female and male speech. We examined the THOR benefit associated with a non-facing masker talker head orientation (relative to a facing orientation) as a function of masker talker facing angle. The target talker always faced the listener, whereas co-located maskers were tested with eight different masker head angles, ranging from 0 degrees (facing the listener) to facing 180 degrees away. Two filtering conditions were tested: full-band and low-pass filtered at 8 kHz. A THOR benefit was observed at masker head angles greater than 45 degrees, increasing from 2 dB to 8 dB between angles of 67.5 degrees and 180 degrees. This benefit was reduced for low-pass filtered speech. Access to EHF cues improved performance, but only for masker head angles &gt;22.5 degrees. There was no significant relationship between 16-kHz pure-tone thresholds and performance for young, normal-hearing listeners with good EHF hearing. These findings indicate that listeners benefit from non-facing masker talker head orientations &gt;45 degrees when the target talker is facing the listener, with greater benefit for larger head angles.</jats:p>