The Neural Mechanism Of Emotional Prosody Processing In Neonates

A proper decoding of vocal emotion cues allows adaptive behavior in accordance with social context.Although previous studies have provided important insights,it remains unclear regarding the neural bases of emotional prosody processing at birth.The current study employed event-related potential and near-infrared spectroscopy to examinethe brain response to sentential prosodies of different emotional categories in neonates.Using an odd-ball paradigm,study 1 showed that the fronto-central scalp distribution of the neonatal brain could discriminate emotional voices from neutral voices;especially the mismatch response(MMR)was larger in response to the deviant stimuli of joy compared with anger.The participants in study 2 lay in bed listening to emotional prosodies while NIRS data were recorded.Results indicated that the right superior temporal gyrus(STG)showed greater activation for emotional than neutral prosody;the left superior frontal gyrus and the right inferior frontal gyrus(IFG)had larger activation for happy than neutral prosody;the right supramarginal gyrus showed increased response to fearful than neutral prosody;and the left angular gyrus exhibited larger activation for happy than neutral prosody.Furthermore,it was found that happy prosodyelicited enhanced neural response relative to fearful(in the right STG)and angry prosodies(in the right IFG),suggesting that the negativity bias is not yet established at birth.This finding has important implications for foetus education and make a contribution to related early developmental theories.