Mother's behavioral corrections tune infant's brain to angry tone

The same brain network that adults use when they hear angry vocalizations is at work in infants as young as six months old, an effect that is strongest in infants whose mothers spend the most time controlling their behavior, according to a new study in the open-access journal PLOS ONE by Chen Zhao of the University of Manchester, UK, and colleagues. The study indicates that the network recruited in adult vocal emotion processing is up and running quite early in life and that its sensitivity to anger is partly a result of maternal interactions. It has been recognized for generations that infants can distinguish the emotional content of their mothers' voices long before they understand words, based on intonation, tone, rhythm, and other elements. In adults, that emotional content is processed in the frontal and temporal lobes. Brain imaging studies in infants have been performed, but the noise of an MRI machine has made an analysis of the response to sounds challenging.