The interaction between talker head orientation, spatial separation, and extended high frequencies for speech-in-speech recognition

Abstract

Speech-in-speech recognition experiments generally involve presentation of stimuli as if target and masker talkers are facing the listener. This is because speech signals are recorded with microphones located in front of the talkers. In real-world situations, masker talkers are often rotated away from the listener, facing their own conversational partners. This head orientation mismatch between the target and masker talkers provides cues that enhance speech recognition, including cues at extended high frequencies (EHFs; >8 kHz) due to the directional nature of EHFs in speech radiation. However, it is unclear how head orientation and EHF cues affect speech recognition when target and masker speech come from different spatial locations, as is the case in realistic multi-talker environments. In the present study, we investigated the EHF benefit in a complex auditory scene involving differences in target and masker head orientation and spatial location. Masker head orientation was either 0° (facing) or 90° (non-facing). Target speech location was 0° azimuth, while masker speech location was either 0° or ±45° azimuth. Preliminary analyses suggest spatial cues provide greater benefit than head orientation cues, and that the EHF benefit is diminished when talkers are spatially separated. [Work supported by NIH grant R01DC019745.]