A Study on the Action Mechanisms of Bright Light in Seasonal Affective Disorder

(1)临床研究：在1周的无药期后，对6例季节性情感障碍住院患者和1例门诊患者进行三步光疗，共30天，分别暴露在亮-暗-亮或暗-亮-暗的光下。照射发生在上午6时至8时之间。采用汉密尔顿抑郁量表（HAMSAD）评估抑郁的临床严重程度。在治疗之前，患者完成了关于他们对这种治疗的期望的问卷调查，并进行了莫兹利人格量表。明亮的光线与HAMSAD评分的显著改善有关，而昏暗的光线没有影响。强光治疗有效组与无效组患者治疗前对光疗的期待程度无显著差异。莫兹利人格量表显示两组在任何项目上都没有差异。结果表明，光疗的临床效果可能是基于光的特定效应。(2)动物实验：长期注射锂和丙咪嗪，观察大鼠体温和活动节律。锂而非丙咪嗪延长了生物节律周期。两种药物都改变了节律的初相。

(1)Clinical Study : Following a 1-week drug-free period, a three step light therapy was applied to six inpatients and one outpatient with seasonal affective disorder for a total of 30 days which involved exposure to either bright-dim-bright light or dim-bright-dim light. The irradiation occurred between 6 : 00 AM and 8 : 00 AM.The clinical severity of depression was evaluated using the Hamilton Rating Scale for Depression, SAD version (HAMSAD). Prior to treatment, the patients completed questionnaires concerning their expectations for this therapy, and the Maudsley Personality Inventory was administered.Bright light was associated with significant improvement in HAMSAD scores, whereas dim light had no effect. The degree of patient's expectation for phototherapy before treatment was not different between the effective group and the ineffective group in bright light therapy. The Maudsley Personality Inventory showed no differences between these two groups in any items. The results suggest that the clinical effects of phototherapy may be based on a specific effect of light.(2)Animal Study : Lithium and imipramine were chronically injected into rats, and rhythms of temperature and activity were measured. Lithium but not imipramine lengthened the period of biological rhythms. Both drugs changed the acrophase of rhythms.