We report a brain imaging study with fMRI in which participants were scanned while watching Noh masks with face expressions rated as happy. Among seventy standard masks previously rated by the participants, we selected the six happiest masks and six neutral masks to explore the neural correlates of happiness associated with Noh masks. Results based on region of interest (ROI) analysis indicated activations of nucleus accumbens (Nacc) while viewing happy masks. We suggest that as the Nacc activation increased, happiness tended to increase possibly due to enhanced dopaminergic activity in the Nacc associated with the reward by observing smiling masks.

Key words: happiness, emotion, facial expression, Noh mask, fMRI