SEASONAL AND NONSEASONAL DEPRESSION AND THE 5-FACTOR MODEL OF PERSONALITY

The purpose of this study was to compare the personality characteristi cs of patients with non-psychotic, major depression, seasonal subtype (SAD) to patients with non-psychotic, major depression, without season ality (non-SAD). The patients were consecutive referrals to a universi ty-affiliated mood disorders outpatient clinic. The personality charac teristics were assessed using the five-factor model of personality (FF M) as measured by the revised NEO Personality Inventory (NEO PI-R). Pa tients were assessed during the acute depressive episode. Controlling for severity of depression, differences were found on only one of the five dimensions, with the SAD patients (n = 43) scoring significantly higher on the Openness dimension than non-SAD patients (n = 57), Based on these results we infer SAD patients may represent a psychologicall y distinct subgroup of depressed patients - more imaginative, more emo tionally sensitive and likely to entertain unconventional ideas than n on-SAD patients. This personality constellation may explain why indivi duals with SAD are more sensitive to and may amplify the mild dysphori a typically associated with winter months.