Certainly, we are all born empathic and sensitive to vibrations. In Evolution's End, Joseph Chilton Pearce describes how, a few days after conception, the embryo forms a clump of vibrating cells that becomes the new heart. These cells seem to be sound sensitive and tune to the mother's heartbeat and breath, which appear to be necessary for further forming the infant's heart. The mother's emotional state, and any repetitive patterns of behavior, are imprinted on the fetus hormonally and through the tone of her voice.