Categorical perception of nonspeech sounds by 2-month-old infants

According to recent investigations, adult listeners perceive rise-time differences in both speech and nonspeech stimuli in a categorical manner (Cutting & Rosner, 1974). Adults labeled sawtooth-wave stimuli as either plucked or bowed. The present study uses the high-amplitude sucking technique to explore the 2-month-old infant’s perception of rise-time differences for sawtooth stimuli. Infants discriminated rise-time differences which marked off the different nonspeech categories, but did not discriminate equal differences within either category. Thus, the present study shows that infants, like adults, can perceive nonspeech stimuli in a categorical manner.