“The sound of the mother’s heartbeat that babies became so familiar with inside the womb becomes imprinted on the embryo before birth and the rediscovery of this familiar sound next to the mother’s left breast after birth produces a vitally familiar and tranquil soothing influence on the infant.” —Judith Land
Holding a baby with the left hand provides a tremendous calming effect because it places the head of the baby closest to the mother’s heart. Through imprinting, unconscious instinct, and trial and error, mothers soon discover that a baby is more at peace if held on the left side against her heart. The sound of the mother’s heart beating brings comfort and reduces infantile crying. Babies who cry less gain more weight and fall asleep quicker.
Metronomes and rhythmic swaying from side to side at the normal heart rate of 72 beats per minute while holding an infant produces similar results that helps lull infants to sleep. Rocking back and forth is a nervous behavior that many people continue into adulthood when confronting insecurities and difficult circumstances.
Cradling a baby with the left hand leaves the right hand free to manipulate the environment, prepare meals, do work, defend against insects, pests and predators, and since the beginning of time communicate using ancient sign language.
The majority of depictions of the Madonna and child show the child cradled in the left arm. Perhaps, it is no accident that most folk music and dancing have a syncopated rhythm. Here again the sounds and movements take the performers back to the safe world of the womb. Is this the secret to the age-old question of handedness?