Effects of tryptophan depletion vs catecholamine depletion in patients with seasonal affective disorder in remission with light therapy.

Abstract

SEASONAL AFFECTIVE disorder, winter type (SAD), is a condition characterized by regularly occurring depressions in fall and winter, alternating with nondepressed periods in spring and summer.¹ Light therapy with bright, fluorescent white light has been shown to be an effective antidepressant.^1-3 Evidence suggests that brain monoaminergic systems may be involved in the pathogenesis of SAD and in the mechanism of action of light therapy.