Please note: This is a companion version & not the original book. Sample Book Insights: #1 The first experiments in fetal hearing were conducted in the early 1920s. By around twenty-eight weeks’ gestation, the fetus can detect sounds. The mother’s voice is especially important for this learning, as it is felt as vibrations against the body. #2 The ability to hear speech in the womb is limited, and the uterine wall muffles voices into an indistinct rumble that allows only the rises and falls of emotional prosody to penetrate. However, after two months of intense focus on the mother’s vocal signal, a newborn emerges into the world clearly recognizing the mother’s voice and showing a marked preference for it. #3 The developing brain works on a use it or lose it basis. Circuitry that is not activated by environmental stimuli is pruned away. The opposite happens for brain circuits that are repeatedly stimulated by the human voice. They grow stronger and more efficient. #4 The voices we hear around us in infancy physically sculpt our brain, pruning away unneeded circuits, strengthening the necessary ones, and specializing the brain for perceiving the specific sounds of our native tongue.