Green Light Effects on Anxiety

The main goal of this study is to determine whether exposure to a narrow band of green light (NBGL) improves outcome of psychotherapy sessions for the treatment of anxiety. This is a within-subject study design that examines NBGL effects (as compared to white light) on anxiety level and treatment success, as evaluated by the treating psychotherapist and the patient. For each participant, the study will consist of 8 therapy sessions, each lasting 60 minutes, in which light conditions will be presented in the following order Session 1: White light, Session 2: white light, Session 3: NBGL (i.e., green light), Session 4: NBGL, Session 5: NBGL, Session 6: NBGL, Session 7: White light, Session 8: White light Effects of lights (white vs.NBGL) on anxiety level will be evaluated at the beginning and end of each therapy session by the patient, using a validated questionnaire. At the end of each session, the treating psychotherapist will fill another evaluation form that summarizes her/his impression of the treatment success or lack of.