Kindling the Spark: Early Development

Alullaby winds its way through the intimate confines of the nursery, as a restless baby is soothed to sleep. The rhythm and rocking chair synchronize a pulse as a mother sings softly to her child. The baby listens to the gentle flow of the melody, which drifts into a hum that vibrates against the sleeping child’s tiny head. A few short years later, Mom smiles as she looks in to her three-year-old’s room. Her daughter is nestled in the same rocking chair, singing a rather lopsided version of the same lullaby, gently stroking a rag doll wrapped in a frayed old baby blanket. Children listen before they are born. They are aware of their mother’s heartbeat and the different environmental sounds that filter into the cozy womb. They are surrounded by the low-pitched pulsating sounds of their mother’s cardiovascular system at work. Studies show that pregnant singers find their babies much quieter when they are singing. Instrumentalists report the opposite effect, with lots of internal activity when they are performing. Even before birth, a child recognizes the sound of a mother’s voice and responds to music or familiar sounds. Prenatal studies abound that can measure the movements and startle reflexes of these yet-to-be-born listeners. Loud, sudden noises (above 100 db) cause the fetal heart to beat faster and an immediate startle response. One experiment zapped 15 seconds of a Bach organ prelude (at 100 db) through headphones nestled close to a mother’s abdomen. Not surprisingly, the fetal heart rate accelerated within five seconds of this musical stimulation. Once a baby is born, the effects of these prenatal sounds still have an influence on behavior. Studies of newborns by Salk in the 1960s resulted in the popularity of crib devices that play the sound of an adult heartbeat to soothe babies to sleep. Other studies show the same soothing effect for seven-day-old neonates listening to taped sounds of intrauterine background noises. From birth, the mother’s voice is distinguished from other women’s voices and recognized more readily than the father’s voice—again stemming from prenatal listening experiences.