Perceiving Body Height From Connected Speech: Higher Fundamental Frequency Is Associated With the Speaker's Height

To a certain degree, human listeners can perceive a speaker's body size from their voice. The speaker's voice pitch or fundamental frequency (Fo) and the vocal formant frequencies are the voice parameters that have been most intensively studied in past body size perception research (particularly for body height). Artificially lowering the Fo of isolated vowels from male speakers improved listeners' accuracy of binary (i.e., tall vs not tall) body height perceptions. This has been explained by the theory that a denser harmonic spectrum provided by a low pitch improved the perceptual resolution of formants that aid formant-based size assessments. In the present study, we extended this research using connected speech (i.e., words and sentences) pronounced by speakers of both sexes. Unexpectedly, we found that raising Fo, not lowering it, increased the participants' perceptual performance in two binary discrimination tasks of body size. We explain our new finding in the temporal domain by the dynamic and time-varying acoustic properties of connected speech. Increased Fo might increase the sampling density of sound wave acoustic cycles and provide more detailed information, such as higher resolution, on the envelope shape.