This is not just what a mother's heart feels but scientists do nod in affirmation as well. According to a new study, the sight of a smiling infant can trigger the 'feel-good' part of the brain which deals with sensations of reward and pleasure. In the study, 28 first-time young mothers were put into a MRI brain scanner and were asked to look at pictures of their own and other babies. As mothers identified their own children, the areas of the brain associated with 'reward' were on alert and the brain chemical dopamine was seen to be active. Dopamine is a key chemical messenger in the body, important for learning, motivating, sleeping and controlling movement. The strength of the reaction depended on the expression of the babies and smiling faces triggered the biggest reaction, while neutral or sad-looking babies provoked the least response. Lead researcher Lane Strathearn said, ''These are the areas that have been activated in other experiments associated with the neurotransmitter dopamine.'' ''It may be that seeing your own baby's smiling face is like a natural high,'' he added.
The study published in the American medical journal Pediatrics further revealed crying babies made little difference to the reward centres of the brain. In fact, mothers reacted to their own crying babies in exactly the same way as a stranger's crying child.