Characterization of fundamental-frequency contours of speech

Fundamental frequency (F0) contours for 60 isolated American English sentences and a text, read by three native speakers, have been analyzed and these contours have been schematized subjectively by ideal patterns. The basic elements (attributes) of the schematic patterns are a baseline (BL) which represents the gradual fall of the F0 contour along the sentence, a piece wise-linear trapezoidal pattern with rising (R) and lowering (L), and a peak (P) which often occurs at the onset of R. The trapezoidal pattern demarcates a sentence into phonetic groups (PGs) of words. Additional attributes are a rising (R1) which can occur at an intermediate content word in PG, and continuation rise. Intraspeaker differences for these schematic patterns were negligible for the sentences investigated. The organization of the patterns seems to be constrained by two primary factors: the structure of the sentence and a principle of physiological economy in the control of F0 during speech. Research supported by an NIH grant.