The structure underlying core affect and perceived affective qualities of human vocal bursts

ABSTRACT

Vocal bursts are non-linguistic affectively-laden sounds with a crucial function in human communication, yet their affective structure is still debated. Studies showed that ratings of valence and arousal follow a V-shaped relationship in several kinds of stimuli: high arousal ratings are more likely to go on a par with very negative or very positive valence. Across two studies, we asked participants to listen to 1,008 vocal bursts and judge both how they felt when listening to the sound (i.e. core affect condition), and how the speaker felt when producing it (i.e. perception of affective quality condition). We show that a V-shaped fit outperforms a linear model in explaining the valence-arousal relationship across conditions and studies, even after equating the number of exemplars across emotion categories. Also, although subjective experience can be significantly predicted using affective quality ratings, core affect scores are significantly lower in arousal, less extreme in valence, more variable between individuals, and less reproducible between studies. Nonetheless, stimuli rated with opposite valence between conditions range from 11% (study 1) to 17% (study 2). Lastly, we demonstrate that ambiguity in valence (i.e. high between-participants variability) explains violations of the V-shape and relates to higher arousal.

KEYWORDS:

• Vocal bursts
• valence and arousal
• core affect
• perception of affective quality
• ambiguity

Acknowledgments

L.C. and G.L. would like to thank Giacomo Handjaras for methodological suggestions and feedback. The authors would like to thank Erika Bucci and Valentina Formica for their help in the collection of study 2 data and Pia Campeggiani for her feedback and support. G.L. was supported by Marie Curie programme grant funding H2020, grant #101026032. V.P. was supported by Ministerio de Ciencia, Innovación y Universidades, postdoctoral fellowship IJC2020-043408-I; Agencia Estatal de Investigación, grant numbers: PID2021-122233OB-I00 and PID2021-128950OB-I00. L.C. was supported by IMT School for Advanced Studies Lucca, under Grant PAI (Progetti di Attività Integrata). M.V. was supported by the University of Bologna under the ALMACurie Fellow program.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by H2020 Marie Sklodowska Curie Actions: [Grant Number 101026032]; Ministerio de Ciencia, Innovación y Universidades: [Grant Number FJC2018-036191-I]; Agencia Estatal de Investigación: [Grant Number PGC2018-093464-B-I00]; IMT School for Advanced Studies Lucca: [Grant Number Progetti di Attività Integrata - PAI]; University of the Basque Country (UPV/EHU): [Grant Number GIU18/221,US20/03]; Basque Government: [Grant Number IT1396-19].