Prospective memory, the inability to remember an intended action, is a common complaint, but not formally assessed in most clinical and research studies of mild cognitive impairment (MCI). In this study, patients with amnestic mild cognitive impairment (aMCI), non-amnestic cognitive impairment (naMCI), and cognitively normal (CN) elders were assessed using the Miami Prospective Memory Test (MPMT). A unique aspect of the paradigm was that participants were scored for intention to perform, accuracy in recollection for specific elements of the task, and the need for reminder cues. Excellent test-retest stability was obtained for MPMT Event-Related (ER), combined Time-Related (TR) subscales, and total MPMT score for aMCI subjects. MPMT impairments were observed in 48.6% of aMCI, 29.4% of naMCI, and 10.0% of normal elderly participants. Prospective memory deficits were common in participants with aMCI, and occurred in almost a third of naMCI participants. Intention to perform and need for reminder cues were significantly more impaired than retrospective memory for specific details of the task. It is concluded that assessment of different elements of prospective memory is important in MCI research and that inability to remember intended actions is a significant feature in those as risk for Alzheimer’s disease. 1. Introduction Amnestic mild cognitive impairment (aMCI) has increasingly been accepted as a prodrome or significant risk factor for Alzheimer’s disease in clinical settings . The vast majority of efforts to assess aMCI have relied on paradigms that focus on retrospective memory. These involve typical list learning tests or measuring episodic memory for passages or visual reproduction tasks. Impairments in delayed recall or rate of forgetting on verbal episodic memory tasks have been found to be a sensitive indicator of mild Alzheimer’s disease (AD) [2, 3] and a predictor of progression to dementia among elders who do not meet criteria for dementia upon initial evaluation [4–6]. Despite these efforts, with the growing understanding that earlier treatments may lead to better outcomes, there is a pressing need to develop tests that are optimally sensitive to different types of memory deficits in the earliest stages of neurodegenerative disorders such as Alzheimer’s disease. Previous memory models have relied on retrospective memory (RM) (i.e., a type of episodic memory), involving remembering events experienced in one’s past. Prospective memory (PM) is another form of episodic memory defined as remembering to carry out intended actions at an
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