Seasonal affective disorder and the yoga paradigm: a reconsideration of the role of the pineal gland.

Seasonal Affective Disorder is a psychiatric disorder whose pathophysiology and clinical presentation are poorly understood. By applying the ancient paradigm of yoga psychology to this subject, new understandings of the syndrome emerge regarding the possible role of the pineal gland, the clinical presentation of the syndrome, and the possible mechanism of action of phototherapy. The energy depletion model presented here ties together such diverse elements as: dose-response aspects of phototherapy, anergia as a primary symptom of SAD, 'spring fever', myofascial pain disorder, the anti-gonadotrophic effect of melatonin, and pineal supersensitivity in bipolar patients. Clinical predictions are made, and simple research protocols are suggested which can directly test the hypotheses generated by this paradigm.