The study goal is to understand how the response to light therapy relates to changes in vision, brain function and improvement in bipolar symptoms. The aims are to investigate mood levels plus the eye and brain responses to visual contrast stimuli in healthy comparators (HC) and bipolar depressed patients.
Study Design and Methods. Overview. The investigators plan to enroll 18-50 year old adults with BD Type I or II and a current episode of major depression on stable-dosed antimanic drugs, and age and sex-matched HC - without mental disorders. Depressed patients with BD will be assigned randomly to receive active light therapy vs inactive comparator for 6 weeks. The investigators will examine responses to contrast stimuli from measures of visual evoked potentials and electro-retinography in HC and depressed bipolar patients before and after 6-weeks of daily midday light therapy. The investigators will assess repeated measures of mood symptom levels, attention and circadian rhythms.