Mnemonic anosognosia in Alzheimer's disease: a test of Agnew and Morris (1998)

Abstract

Agnew and Morris [Agnew, S. K. & Morris, R. G. (1998). The heterogeneity of anosognosia for memory impairment in Alzheimer's disease: A review of the literature and a proposed model. Aging and Mental Health, 2, 9-15] model of awareness for memory functioning has attempted to account for the variance of anosognosia exhibited within the Alzheimer's disease (AD) population. There has been tentative evidence to suggest that the mnemonic anosognosia sub-type, proposed by this model, is common within the early stages of AD. However, this study is the first directly to test the model. Eighteen older adults with early AD and 18 healthy older adults were recruited. Awareness of memory functioning was monitored using patient-performance measures of "task specific" awareness; a measure of global memory awareness; and a patient-informant measure. The stability of participants' awareness was measured across three word recall lists and after a 20-min delay. Results suggested that, whilst the participants with early AD were less aware of their memory ability than the healthy older adults, they were able to improve their awareness following exposure to a memory task. Furthermore, the improvements in awareness were largely retained after the delay period. These findings are discussed in relation to Agnew and Morris [Agnew, S. K. & Morris, R. G. (1998). The heterogeneity of anosognosia for memory impairment in Alzheimer's disease: A review of the literature and a proposed model. Aging and Mental Health, 2, 9-15] model of mnemonic anosognosia and to current thinking about autobiographical memory.