The response to vibroacoustic stimulation was evaluated in 30 healthy full-term newborns and in five newborns with severe neurologic deficits. The stimulus was applied during a period of quite sleep and a subsequent period of quiet sleep served as the control. All 30 healthy newborns reacted by changing from a state of quite sleep to an active sleep state as determined by heart rate acceleration, irregular respiration, and the appearance of limb movements. Heart rate increased by 19.5 +/- 9.7 beats/min (mean +/- SD) for a mean duration of 21.4 +/- 11.9 seconds. The five newborns with severe neurologic deficits did not show any response to vibroacoustic stimulation, and auditory brainstem evoked responses were also absent. We conclude that this technique may be useful as a screening procedure in the evaluation of the neurologic integrity of newborn infants.