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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    • "ption of this neural circuit may contribute to memory decline during the progression of the disease . Functional magnetic resonance imaging ( fMRI ) studies show decreased activity and connectivity of the hippocampus , and temporal and prefrontal cortices during episodic memory tasks in AD patients [ ( Press et al . , 1989 ; Small et al . , 1999 ; Sperling et al . , 2003 ; Pariente et al . , 2005 ; Bai et al . , 2009 ) , for review see ( Dickerson and Sperling , 2009 ) ] . By contrast , MCI subjects show abnormal activation of the hippocampus and EC during face - name , visual object and verbal associative memory tasks ( Dickerson et al . , 2005 ; Hamalainen et al . , 2007 ; Kircher et al . , 2007 ) . C"
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