Psychosomatic Medicine 26:661-670 (1964)
© 1964 American Psychosomatic Society

Normal Heartbeat Sound and the Behavior of Newborn Infants--A Replication Study

¹ Departments of Psychiatry, Pediatrics, Physiology and Medicine, University of Rochester Medical Center, Rochester, N. Y.; Department of Pediatrics, University of Colorado Medical Center, Denver, Colorado
² Departments of Psychiatry, Pediatrics, Physiology and Medicine, University of Rochester Medical Center, Rochester, N. Y.
³ Departments of Psychiatry, Pediatrics, Physiology and Medicine, University of Rochester Medical Center, Rochester, N. Y.; Laboratory of Comparative Psychology, University of Illinois, Urbana, Illinois
⁴ Departments of Psychiatry, Pediatrics, Physiology and Medicine, University of Rochester Medical Center, Rochester, N. Y.; Departments of Psychiatry and Pediatrics, University of Colorado Medical Center, Denver, Colorado

A group of infants exposed to a simulated heartbeat sound at 45 decibels during the first 4 days of life did not respond differently in terms of weight gain, activity, or formula intake from a group of control infants not so exposed. A significant positive correlation between weight gain and food intake was noted. Some of the pertinent differences between this replication and the previous study by Salk are considered in an effort to clarify some of the questions of design and the differences in findings.