Brain Impairment

Articles

Domain-Specific Anosognosia in Alzheimer's Disease and Vascular Dementia

Marco Tamiettoa1 c1, Luca Latini Corazzinia2, Lorys Castellia3 and Giuliano Geminiania4

a1 Department of Psychology and Center for Cognitive Science, University of Turin, Italy.

a2 Department of Psychology and Center for Cognitive Science, University of Turin, Italy.

a3 Department of Psychology and Center for Cognitive Science, University of Turin, Italy.

a4 Department of Psychology and Center for Cognitive Science, University of Turin, Italy.

Abstract

The present study investigated the relationship between anosognosia for cognitive, functional and psychopathological disorders in Alzheimer's disease (AD) and vascular dementia (VD). Ten patients with probable Alzheimer's disease and 10 patients with probable vascular dementia were matched for age, education, illness duration and dementia severity. Cognitive, functional and psychopathological characteristics of the patients were assessed by means of different self-rating scales. The same questionnaires were submitted to patients' caregivers, blind to the patients' answers. Anosognosia was defined as the positively signed difference between patients' and caregivers' ratings. Three anosognosia indices for each domain investigated were obtained. We found lack of insight to be a common and consistent feature of AD and VD. However, unawareness for cognitive and functional domains was more severe in AD than in VD. Furthermore, in AD patients anosognosia for cognitive, functional and psychopathological domains dissociated from one another, as shown by lack of significant correlations between the three indices. Conversely, in VD patients these three anosognosic domains were closely related, indicating a generalised unawareness. These findings suggest that heterogeneity of anosognosic deficits may help differentiate AD from VD.

Correspondence:

c1 Address for correspondence: Marco Tamietto, Dipartimento di Psicologia, Università degli Studi di Torino, Via Po 14, 10123, Torino, Italy. E-mail: tamietto@psych.unito.it