 A total of 100 participants will be recruited. Clinical measurements of mood status by Becks Depression Inventory and Becks Anxiety Inventory, as well as job stress by Chinese Version of the Job Content Questionnaire and the Chinese version of Copenhagen Burnout Inventory will be arranged. The relationship between clinical measurements and cortical activity during a VFT will be analyzed by Pearsons correlation. Multiple regression analysis will be applied to investigate the independent contributions of mood status and job stress. 