Lack of motivation may serve as a diagnostic criteria for Alzheimer’s disease. According to a discussion during the European Alzheimer’s Disease Consortium earlier this month, the apathy may be caused by functional impairment (1). The researchers noted that reduced “goal-oriented behavior, goal-directed cognitive activity and emotions” must persist over time, thought to be “at least four weeks”.
1. Robert P, Onyike CU, Leentjens AF et al. Proposed diagnostic criteria for apathy in Alzheimer's disease and other neuropsychiatric disorders. Eur Psychiatry 2009;24:98-104.