fMRI studies of associative encoding in young and elderly controls and mild Alzheimer’s disease

Memory Disorders Unit, Department of Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA.
Journal of Neurology Neurosurgery & Psychiatry (Impact Factor: 6.81). 02/2003; 74(1):44-50.
Source: PubMed


To examine alterations in patterns of brain activation seen in normal aging and in mild Alzheimer's disease by functional magnetic resonance imaging (fMRI) during an associative encoding task.
10 young controls, 10 elderly controls, and seven patients with mild Alzheimer's disease were studied using fMRI during a face-name association encoding task. The fMRI paradigm used a block design with three conditions: novel face-name pairs, repeated face-name pairs, and visual fixation.
The young and elderly controls differed primarily in the pattern of activation seen in prefrontal and parietal cortices: elderly controls showed significantly less activation in both superior and inferior prefrontal cortices but greater activation in parietal regions than younger controls during the encoding of novel face-name pairs. Compared with elderly controls, the Alzheimer patients showed significantly less activation in the hippocampal formation but greater activation in the medial parietal and posterior cingulate regions.
The pattern of fMRI activation during the encoding of novel associations is differentially altered in the early stages of Alzheimer's disease compared with normal aging.

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Available from: Dorene Rentz, Dec 16, 2013
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    • "been shown that while younger adults do show such PFC modulation (Addis et al., 2014, Rand Givannetti et al., 2006, Sperling et al., 2003), older adults do not upregulate PFC activity in response to increased encoding task demands. For example,Addis et al. (2014)used a semanticrelatedness encoding task to investigate parametric responses in PFC regions to generation demands. "
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