Infant recognition of mother's voice.

Each of a group of one-month-old infants was reinforced, contingent upon nonutritive sucking, with its mother's voice and the voice of a stranger. In this experiment, two conditions were applied. Under the first, the mother's speech was aimed at communicating with the infant, while, under the second, the mother's speech lacked prosodic and intonational aspects of normal speech. It was shown that infants will suck more for their mother's voices under the intonanted condition only. It was concluded that a young infant prefers its own mother's voice provided the mother speaks normally.