Many acoustic features convey emotion similarly in speech and music. Researchers have established that acoustic features such as pitch height, tempo, and intensity carry important emotional information in both domains. In this investigation, we examined the emotional significance of melodic and rhythmic contrasts between successive syllables or tones in speech and music, referred to as Melodic Interval Variability (MIV) and the normalized Pairwise Variability Index (nPVI). The spoken stimuli were 96 tokens expressing the emotions of irritation, fear, happiness, sadness, tenderness, or no emotion. The music stimuli were 96 phrases, played with or without performance expression and composed with the intention of communicating the same emotions. Results showed that nPVI, but not MIV, operates similarly in music and speech. Spoken stimuli, but not musical stimuli, were characterized by changes in MIV as a function of intended emotion. The results suggest that these measures may signal emotional intentions differently in speech and music.
Keywords: emotional communication; melodic variability index; music cognition and perception; normalized pairwise variability index; speech prosody.