Negative emotions in the target speaker's voice enhance speech recognition under "cocktail-party" environments

Under a "cocktail-party" environment with simultaneous multiple talkers, recognition of target speech is effectively improved by a number of perceptually unmasking cues. It remains unclear whether emotions embedded in the target-speaker's voice can either improve speech perception alone or interact with other cues facilitating speech perception against a masker background. This study used two target-speaker voices with different emotional valences to examine whether recognition of target speech is modulated by the emotional valence when the target speech and the maskers were perceptually co-located or separated. The results showed that both the speech recognition against the masker background and the separation-induced unmasking effect were higher for the target speaker with a negatively emotional voice than for the target speaker with a positively emotional voice. Moreover, when the negative voice was fear conditioned, the target-speech recognition was further improved against speech informational masking. These results suggested that the emotionally vocal unmasking cue interacts significantly with the perceived spatial-separation unmasking cue, facilitating the unmasking effect against a masking background. Thus, emotional features embedded in the target-speaker's vocal timbre are also useful for unmasking the target speech in "cocktail-party" environments.