Neonatal Pain Cries: Effect of Circumcision on Acoustic Features and Perceived Urgency

Abstract

The relation between neonatal pain cry features elicited by painful circumcision procedures and the perceived urgency of those cries was investigated. Vocalizations were recorded during circumcision of 30 normal newborn males, analyzed by spectrographic methods and validated with computer intervals; shorter, more frequent vocalizations; higher peak fundamental frequencies; fewer harmonics; and greater variability of the fundamental. Cries elicited by the most intrusive procedures were judged by adult listeners to be the most urgent, and cries from similarly invasive procedures were judged to be of the same degree of urgency. Cries appeared to be judged along 3 dimensions described by harmonic, temporal, and pitch characteristics. Subjective judgments and objective quantitative data converge to demonstrate that infants' cries are perceived as varying and objectively, do systematically vary with respect to the the intensity of the painful stimuli.