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Abstract:
Abstract: Difficulty associating names with faces is a common
complaint of older individuals, and raises fears of developing
Alzheimer's disease (AD). We used functional MRI to investigate the
functional network subserving face-name association, and to examine
alterations in patterns of activation that occur with normal aging
and mild AD. Eight healthy young subjects (YS, age 23-33), 10
healthy elderly subjects (OS, age 67-88), and 7 AD patients (AD,
age 71-89) with mild dementia severity (MMSE 20-25) were studied.
Whole brain EPI BOLD fMRI was performed with a 3T GE Scanner, while
subjects were shown unfamiliar faces with fictional first names in
alternating blocks of novel and repeated face-name pairs and visual
fixation. YS, OS, and AD subjects all showed significant activation
(p>0.000001) in fusiform regions. YS and OS, but not AD
subjects showed significant activation in the hippocampal
formation. YS showed greater activation in dorsolateral prefrontal
regions than OS, but OS showed greater activation than YS in
superior parietal regions. Post-scan memory testing showed
significant differences between all groups in both face recognition
and free recall of names. Our results suggest that this task
activates a functional network which includes the fusiform gyri,
the hippocampal formation, superior parietal and dorsolateral
prefrontal cortices, and that the components of this network are
differentially affected by the processes of normal aging and
AD.
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