Maternal holding preferences: a consequence of newborn head-turning response

Salk observed that in an overwhelming majority of cases (80%) mothers prefer to hold their infants across the left shoulder. This preference occurs over a diversity of cultures and is not related to the hand preference of the mother. Salk suggested a fetal imprinting to the sound of the heartbeat as the mechanism responsible for this phenomenon. While such speculation is intriguing, it is not scientifically testable. 2 experiments were performed to examine a more testable hypothesis. Results of these studies suggest that the initial head-turning preference of an infant is related to the holding preference of its mother.