Effects of season on electro-oculographic ratio in winter seasonal affective disorder

Clinical Psychobiology Branch, National Institute of Mental Health, Building 10, Room 4S-239, 9000 Rockville Pike, Bethesda, MD 20892, USA
Psychiatry Research (Impact Factor: 2.68). 12/1995; DOI: 10.1016/0165-1781(95)02788-2

ABSTRACT Low electro-oculographic (EOG) ratios have been reported in patients with seasonal affective disorder (SAD) during the winter. This study evaluated the effects of the changing seasons on EOG ratios in SAD patients. Sixteen outpatients with SAD and 16 age-, sex-, and medication-matched normal volunteers had EOG testing during the winter and again during the summer. There was a significant season × group interaction in EOG ratios, with normal subjects showing higher ratios in winter than in summer — a seasonal variation not observed in SAD patients. SAD patients may have a subsensitivity to environmental light that leads them to experience symptoms during the winter.

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