New perspectives on subjective memory complaints

One of the enduring issues in our field is the meaning of memory complaints. Despite extensive research over the past 30 years, there is still considerable controversy about what memory complaints signify. Are the concerns that older people express harbingers of the onset of dementia, markers of normal, age-related changes, the result of mislabeling ordinary lapses in memory that occur at any age as due to old age or senility, or part of the exaggerated, negative beliefs of people who are depressed? Three papers in this issue and a fourth in the November 2007 issue (Oyebode et al., 2007) provide fresh perspectives on memory complaints. These papers are noteworthy in their breadth. Reflecting widespread interest in this issue, the papers come from four different countries (The Netherlands, Portugal, United Kingdom, United States). They use different sampling approaches, ranging from a national, representative sample (Sachs-Ericsson, Joiner & Blazer) to small and selected sample of patients with early stage Alzheimer’s disease (Oyebode, Southall, Hardy & Austin). In three of the papers (Mendes, Ginó, Ribeiro, Guerreiro, de Sousa, Ritchie & Mendonça; Oyebode et al.; Sachs-Ericsson et al.) the meaning of memory complaints is clarified in part through comparisons with how younger people evaluate their memory. The tools used to assess memory and memory complaints in these studies are also varied, from simple, single-item measures of complaint to complex, ecologically-based assessments of complaint and performance. Two of the papers provide clarification of the role of depression for memory complaints. Mendes and colleagues explore complaints in healthy populations of young and older adults. They find that complaints are common in both groups and depressive symptoms, not objective memory performance, is the primary correlate of complaints. Sachs-Ericcson and colleagues explore the relation of memory complaints to prior psychiatric diagnosis in a well-characterized and representative sample. After controlling for current symptoms, they report that a history of past depressive episodes, but not other psychiatric problems, contributes to perceptions of poorer memory. The unique role of depression in memory complaint may reflect the characteristic attributional style of people with depressive disorders or that biological mechanisms in depression increase the risk of dementia in old age (Alexopoulos, 2006). Mol and her colleagues (Mol, Ruiter, Verhey, Dijkstra & Jolles) use a theory-based approach to broaden the list of possible determinants of subjective complaints. They find that low memory self-efficacy, negative attitudes about one’s own memory, high memory-related anxiety and anticipating negative reactions from other people were associated with perceived forgetfulness. These results confirm Bandura’s (1989) formulation of the role of selfefficacy in cognitive processes and appraisals and highlight the key role of self-efficacy in adaptation in later life (Blazer, 2002). Finally, Oyebode and colleagues explore awareness of memory functioning in people with early stage Alzheimer’s Disease, as well as young and old controls. In contrast to the other three papers, they do not assess global complaints of memory loss, but instead ask participants to rate their performance before and after completing an ecologically-valid memory task. Findings indicate that older people with dementia are overly optimistic about their performance while younger persons are more pessimistic about how they perform. Interestingly, normal older participants are the most realistic. Of perhaps practical significance, persons with Alzheimer’s disease were able to adjust their evaluations of performance in the post-test ratings, which has implications for the use of rehabilitation strategies with this population (Clare & Woods, 2005; Clare, Wilson, Carter, Roth, & Hodges, 2004). Looking beyond these papers, I can suggest three issues that need more careful attention in future studies. First, we will do better studies of the relation of memory complaints and functioning when we have better measures of subjective complaints and memory processes. Global measures of memory complaints may be more susceptible to reflecting age stereotypes and attribution style, rather than memory functioning. An inherent problem in asking people about their memory is that we assume they can reliably recall past episodes of forgetting, which, of course, may or may not be the case. Real time and diary methods may be more powerful tools for identifying what types of memory lapses occur and how frequent they are. We also need to do a better job of evaluating complaints about specific types of forgetting with equivalent memory tasks. Most people do not complain about problems learning and remembering items from a list, yet that is the type of memory we often assess in trying to relate memory complaints and performance. By contrast, older people are more likely to be concerned about prospective memory, such as remembering to do an errand or go to an appointment, or about difficulties recalling names or words. These processes have rarely been evaluated in studies of memory complaints.