Skip to main content Accessibility help
×
×
Home

Neuroanatomic substrates of semantic memory impairment in Alzheimer's disease: Patterns of functional MRI activation

  • ANDREW J. SAYKIN (a1), LAURA A. FLASHMAN (a1), SALLY A. FRUTIGER (a1), STERLING C. JOHNSON (a1), ALEXANDER C. MAMOURIAN (a1), CHAD H. MORITZ (a1), JUDITH R. O'JILE (a1), HENRY J. RIORDAN (a1), ROBERT B. SANTULLI (a1), CYNTHIA A. SMITH (a1) and JOHN B. WEAVER (a1)...
    • Published online: 01 July 1999
Abstract

Impairment in semantic processing occurs early in Alzheimer's disease (AD) and differential impact on subtypes of semantic relations have been reported, yet there is little data on the neuroanatomic basis of these deficits. Patients with mild AD and healthy controls underwent 3 functional MRI auditory stimulation tasks requiring semantic or phonological decisions (match–mismatch) about word pairs (category–exemplar, category–function, pseudoword). Patients showed a significant performance deficit only on the exemplar task. On voxel-based fMRI activation analyses, controls showed a clear activation focus in the left superior temporal gyrus for the phonological task; patients showed additional foci in the left dorsolateral prefrontal and bilateral cingulate areas. On the semantic tasks, predominant activation foci were seen in the inferior and middle frontal gyrus (left greater than right) in both groups but patients showed additional activation suggesting compensatory recruitment of locally expanded foci and remote regions, for example, right frontal activation during the exemplar task. Covariance analyses indicated that exemplar task performance was strongly related to signal increase in bilateral medial prefrontal cortex. The authors conclude that fMRI can reveal similarities and differences in functional neuroanatomical processing of semantic and phonological information in mild AD compared to healthy elderly, and can help to bridge cognitive and neural investigations of the integrity of semantic networks in AD. (JINS, 1999, 5, 377–392.)

Copyright
Corresponding author
Reprint requests to: Andrew Saykin, Brain Imaging Laboratory, Department of Psychiatry/DHMC, Dartmouth Medical School, Lebanon, NH 03756. E-mail: saykin@dartmouth.edu
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Journal of the International Neuropsychological Society
  • ISSN: 1355-6177
  • EISSN: 1469-7661
  • URL: /core/journals/journal-of-the-international-neuropsychological-society
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed