Speech Prosodies of Different Emotional Categories Activate Different Brain Regions in Adult Cortex: an fNIRS Study

Emotional expressions of others embedded in speech prosodies are important for social interactions. This study used functional near-infrared spectroscopy to investigate how speech prosodies of different emotional categories are processed in the cortex. The results demonstrated several cerebral areas critical for emotional prosody processing. We confirmed that the superior temporal cortex, especially the right middle and posterior parts of superior temporal gyrus (BA 22/42), primarily works to discriminate between emotional and neutral prosodies. Furthermore, the results suggested that categorization of emotions occurs within a high-level brain region-the frontal cortex, since the brain activation patterns were distinct when positive (happy) were contrasted to negative (fearful and angry) prosody in the left middle part of inferior frontal gyrus (BA 45) and the frontal eye field (BA8), and when angry were contrasted to neutral prosody in bilateral orbital frontal regions (BA 10/11). These findings verified and extended previous fMRI findings in adult brain and also provided a "developed version" of brain activation for our following neonatal study.