Metamemory in Alzheimer's disease.

Alois Alzheimer's first publication describes his patient's inability to be aware of her condition. One hundred years later, whether or not Alzheimer's disease (AD) patients show impaired awareness of their memory deficits is still of debate. This review makes a novel contribution, arguing that the ideal empirical tool to assess this question is the metamemory framework. The fact that the metamemory framework offers models of healthy memory and metamemory function and ready-developed measures mapped onto theoretical constructs, means that it is a useful paradigm to explore the question of memory awareness. The review focuses on two as yet separate approaches: the neuropsychological models of anosognosia as well as the metamemory framework. Metamemory constructs and measures are used to evaluate Alzheimer's patients' awareness of their memory difficulties by relating the main findings to the existing neuropsychological model of anosognosia. With this approach, only very specific deficits in awareness are found: a failure to update self-beliefs, and a deficit in monitoring episodic memory, possibly related to a deficit in effortful, conscious control processes. This review also considers how the exploration of the neural correlates of metamemory can help to draw novel hypotheses on the brain regions implicated in anosognosia in AD.