Impression of speaker's personality and the naturalistic qualities of speech: Speech rate and pause duration

The present study investigated the relation between temporal structures of speech and listeners' impressions of the speaker's personality. The following speech stimuli were manipulated in paragraph-length speeches: speech durations of sound region (65%-147%) and duration of pause (56%-178%). University students (444 men, 137 women, 18-23 years of age) listened to the experimental stimuli and rated their impression of each speaker's personality and qualities of the speech. Pause duration did not distinctly affect impressions of the spakers' personality, whereas speech rate did. Characteristic quadratic functions provided good approximations of each "Big Five" trait from the Five-Factor Model of personality. Evaluations of Conscientiousness were high when speech was fast, and declined sharply for slower speech. In contrast, Agreeableness was rated high with slow speech, and dropped as speech became faster. Ratings of Extraversion and Openness to Experience were high for relatively rapid speech, and decreased somewhat when speech was faster or slower. Naturalness of speech was rated highest at the original speech rate, and declined symmetrically for faster or slower speech. Listeners' impression of each personality trait appears to have a unique changing pattern. Overall, the results supported the hypothesis that a formulation combining five approximations of personality traits can estimate the entire personality image.