Sensory consonance and the perceptual similarity of complex-tone harmonic intervals: tests of adult and infant listeners.

Two experiments examined the influence of sensory consonance on the perceptual similarity of simultaneous pairs of complex tones (harmonic intervals). In experiment 1, adults heard a sequence of five consonant intervals (each a perfect fifth, or 7 semitones) and judged whether a subsequently presented test interval was a member of the sequence. Discrimination performance was better when the test interval was dissonant (tritone, 6 semitones) rather than consonant (perfect fourth, 5 semitones), despite the fact that the change in interval width was twice as great for the consonant than for the dissonant comparison. In experiment 2, 7-month-old infants were tested with an operant headturn procedure in a similar design and exhibited an identical pattern of responding. Hence, for both age groups, consonance was more important than interval width in determining the perceived similarity of harmonic intervals.