Superior communication of positive emotions through nonverbal vocalisations compared to speech prosody

Abstract

The human voice communicates emotion through two different types of vocalisations: nonverbal vocalisations (brief non-linguistic sounds like laughs) and speech prosody (tone of voice). Research examining recognisability of emotions from the voice has mostly focused on either nonverbal vocalisations or speech prosody, and included few categories of positive emotions. In two preregistered experiments, we compare human listeners’ (total n = 400) recognition performance for 22 positive emotions from nonverbal vocalisations (n = 880) to that from speech prosody (n = 880). The results show that listeners were more accurate in recognising most positive emotions from nonverbal vocalisations compared to prosodic expressions. Furthermore, acoustic classification experiments with machine learning models demonstrated that positive emotions are expressed with more distinctive acoustic patterns for nonverbal vocalisations as compared to speech prosody. Overall, the results suggest that vocal expressions of positive emotions are more distinctive in terms of acoustic patterns when expressed as nonverbal vocalisations than as speech prosody, resulting in superior recognition of positive emotions from nonverbal vocalisations.

Associations between vocal emotion recognition and socio-emotional adjustment in children

“…Interpreting prosodic cues might be challenging, as indicated by evidence (that we replicated) that emotion recognition accuracy is lower for emotional prosody compared with non-verbal vocalizations and facial expressions (e.g. [13][14][15]). This increased difficulty might be because prosodic cues are embedded in speech, which constrains acoustic variability [8].…”

“…[9][10][11][12]). But it has also been shown that emotion recognition accuracy is higher for non-verbal vocalizations compared with prosody [13][14][15].…”

Associations Between Vocal Emotion Recognition and Socio-emotional Adjustment in Children

“…Emotional prosody cues help us build up a mental representation of other’s emotional states (Grandjean, 2020), and prosody can convey a wide range of complex and nuanced states, such as verbal irony, sarcasm and confidence (Cheang & Pell, 2008; Morningstar et al, 2018; Pell & Kotz, 2021). Interpreting prosodic cues might be challenging, as indicated by evidence (that we replicated) that emotion recognition accuracy is lower for emotional prosody compared to nonverbal vocalisations and facial expressions (e.g., Hawk et al, 2009; Kamiloglu et al, 2020; Sauter et al, 2013). This increased difficulty might be because prosodic cues are embedded in speech, which constrains acoustic variability (Scott et al, 2010).…”

“…Based primarily on studies with adult samples, we know that listeners can accurately identify a range of positive and negative emotions from the two types of vocal emotional cues, even when they are heard in isolation and without contextual information (e.g., Castro & Lima, 2010;Cowen et al, 2019;Lima et al, 2013a;Sauter et al, 2010). But it has also been shown that emotion recognition accuracy is higher for nonverbal vocalisations than for emotional prosody (Hawk et al, 2009;Kamiloglu et al, 2020;Sauter et al, 2013). recognition of emotional prosody are further reported in clinical conditions in which deficits in social functioning prevail, namely in individuals at high risk for psychosis and firstepisode schizophrenia (Amminger et al, 2012).…”