Study on the perception of nonlinguistic information of noise-vocoded speech under noise and/or reverberation conditions

Abstract

It has been known that noise and reverberation greatly affect the perception of linguistic information, in particular speech intelligibility. However, the effect of noise and reverberation on the perception of non-linguistic information has not been clarified. We investigated how these types of disturbances affect the perception of non-linguistic information (speaker individuality and vocal emotion) of noise-vocoded speech. We conducted speaker-distinction and vocal-emotion-recognition experiments using noise-vocoded speech created from the speech in noisy, reverberation, and noisy reverberant environments as stimuli. We used seven noise conditions (signal-to-noise ratio (SNR) = 1; 20; 15; 10; 5; 0; À5 dB) and six reverberation conditions (reverberation time (T R ) = 0:0; 0:1; 0:3; 0:5; 1:0; 2:0 s). In both speaker-distinction and vocal-emotion-recognition experiments, the main effects of noise and reverberation were significant, but the interaction was not significant. From these results, except for extremely poor sound conditions, under daily noise and reverberation conditions (an SNR of more than 10 dB and T R less than 1.0 s), there were no significant effects of noise and reverberation.

Contributions of Temporal Modulation Cues in Temporal Amplitude Envelope of Speech to Urgency Perception

“…Our previous experiments in which we systematically varied the number of channels in the NVS scheme and the upper limitation of the modulation frequency components [11,12] demonstrated that temporal modulation cues play a key role in the recognition of both vocal emotion and speaker individuality, particularly at modulation frequencies lower than 8 Hz. Our research has also demonstrated that these features are robust to noise and reverberation [13,14]. However, we have still not clarified the influence of temporal modulation cues in non-linguistic information such as that used in emergency situations.…”