Neuroanatomical correlates of unawareness of memory deficits in early Alzheimer's disease.

Department of Geriatric Medicine, Tokyo Medical University, Tokyo, Japan.
Dementia and Geriatric Cognitive Disorders (Impact Factor: 2.79). 02/2008; 25(4):347-53. DOI: 10.1159/000119594
Source: PubMed

ABSTRACT To investigate neuroanatomical substrates of unawareness of memory deficits in patients with early Alzheimer's disease (AD).
We compared regional perfusion deficits between AD patients with awareness (n = 19) and unawareness (n = 19). SPECT data were analyzed by statistical brain imaging method.
Statistical maps demonstrated a more extensive and severe reduction in perfusion in the unaware group than in the aware group. Quantitative analysis demonstrated a significant difference between the groups in the right subcallosal, anterior cingulate and cingulate gyri and left orbital, subcallosal, and anterior cingulate gyri.
Functional damage to the inferior, medial and orbital frontal lobes as well as the anterior cingulate gyri may be associated with the lack of awareness in patients with early AD.

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