The role of auditory stimuli in crying inhibition in the neonate.

An experiment on the latency and duration of the cessation of spontaneous crying supported evidence that a low frequency intense auditory stimulus inhibits crying in neonates. There was a slight increase in the length of the first pause in crying during exposure to a 200-c/s tone, but no difference in the latency of this first pause. Since crying intensity reaches 80 db SPL at the infant ear, it is hypothesized that auditory stimuli juxtaposed during crying is in fact masked. Hence to be effective, an auditory stimulus must be presented at the beginning of a natural pause in crying. An experiment on rhythm in cry patterns did not support the hypothesis that crying may be a naturally rhythmic pattern of behavior analogous to sucking and susceptible to psychophysical investigation. There was a large variance within and between Ss for the mean latency and duration of cry bursts and pauses. Exper. III asked mothers with infants of 10 days, 7 weeks, and 13 weeks of age to keep a crying activity schedule in their own homes. This study revealed a discontinuity between neonates and older infants in the conditions and patterns of crying. Interview data did indicate that reliable positive orienting responses did occur to natural auditory stimuli in a naturalistic setting.