BACKGROUND: The purpose of this study was to assess the possible role of major stressful life events, complicated grief, and depression in the pathogenesis of benign essential blepharospasm (BEB) and hemifacial spasm (HFS). METHODS: This was a case-control study involving 23 participants with BEB/HFS and 23 control subjects, comparing the frequency of major stressful life events, depression on the Beck Depression Inventory-II, and complicated grief on the Inventory of Complicated Grief. RESULTS: There was no difference in the rate of depression or complicated grief between participants with BEB/HFS (57%) and control subjects (48%). Participants with BEB/HFS experienced a significantly (P = 0.0048) shorter time interval between two major stressful life events (median, 0.3 year) than did the control group (median, 3.0 years). The proportion of participants who had suffered two major stressful lifetime events separated by 1 year or less was significantly greater for participants with BEB/HFS than for control subjects (P = 0.0007). CONCLUSIONS: The onset of BEB and HFS was often preceded by a major lifetime stressor. The development of these conditions was significantly related to the number of stressful life events occurring within the preceding year rather than to the total number of stressful life events. Subjects who sustain closely spaced stressful life events may be at increased risk of developing BEB and HFS.