Body exposure and vocal analysis: validation of fundamental frequency as a correlate of emotional arousal and valence

Abstract

IntroductionVocal analysis of fundamental frequency (f0) represents a suitable index to assess emotional activation. However, althoughf0 has often been used as an indicator of emotional arousal and different affective states, its psychometric properties are unclear. Specifically, there is uncertainty regarding the validity of the indices off0meanandf0variabilitymeasures(f0dispersion,f0range, andf0SD) and whether higher or lowerf0 indices are associated with higher arousal in stressful situations. The present study therefore aimed to validatef0 as a marker of vocally encoded emotional arousal, valence, and body-related distress during body exposure as a psychological stressor.MethodsN= 73 female participants first underwent a 3-min, non-activating neutral reference condition, followed by a 7-min activating body exposure condition. Participants completed questionnaires on affect (i.e., arousal, valence, body-related distress), and their voice data and heart rate (HR) were recorded continuously. Vocal analyses were performed using Praat, a program for extracting paralinguistic measures from spoken audio.ResultsThe results revealed no effects forf0 and state body dissatisfaction or general affect.F0meancorrelated positively with self-reported arousal and negatively with valence, but was not correlated with HRmean/maximum. No correlations with any measure were found for anyf0variabililtymeasures.DiscussionGiven the promising findings regardingf0meanfor arousal and valence and the inconclusive findings regardingf0 as a marker of general affect and body-related distress, it may be assumed thatf0meanrepresents a valid global marker of emotional arousal and valence rather than of concrete body-related distress. In view of the present findings regarding the validity off0, it may be suggested thatf0mean, but notf0variabilitymeasures, can be used to assess emotional arousal and valence in addition to self-report measures, which is less intrusive than conventional psychophysiological measures.