Researchers including AICE members Roza Kamiloglu and Disa Sauter published a new study showing human listeners can infer behavioural contexts from vocalizations of chimpanzees.
A new study from AICE members Roza Kamiloglu and Disa Sauter together with Katie Slocombe (York university) and Daniel Haun (MPI for Evolutionary Anthropology, Leipzig) demonstrates that human listeners can accurately infer particular behavioural contexts like threat, play, and food from chimpanzee vocalizations.
In two experiments, they examined human listeners’ ability to infer behavioural contexts (e.g., discovering food) and core affect dimensions (arousal and valence) from 155 vocalizations produced by 66 chimpanzees in 10 different positive and negative contexts at high, medium, or low arousal levels. In Experiment 1, listeners (n = 310), categorised the vocalizations in a forced-choice task with 10 response options, and rated arousal and valence. In Experiment 2, participants (n = 3120) matched vocalizations to production contexts using Yes/No response options. The results show that listeners were accurate at matching vocalizations of most contexts in addition to inferring arousal and valence. Judgments were more accurate for negative as compared to positive vocalizations. An acoustic analysis demonstrated that, listeners made use of brightness and duration cues, and relied on noisiness in making context judgements, and pitchto infer core affect dimensions. Overall, the results suggest that human listeners can infer affective information from chimpanzee vocalizations beyond core affect, indicating phylogenetic continuity in the mapping of vocalizations to behavioural contexts.
A representative vocalisation for each behavioural context can be listened from here.