a1 Psychology Service, Department of Veterans Affairs Medical Center, San Diego, CA 92161
a2 Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, CA 92093
a3 Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093
The present study examined the relationship between rate of cognitive decline in patients with Alzheimer's disease (AD) and the integrity of the network of associations that comprise their semantic knowledge. The integrity of the semantic network of 12 AD patients was determined by comparing their networks to a standard normal control network derived with Pathfinder analysis, a multidimensional graphic analysis technique. A simple linear regression analysis, comparing the degree of semantic network deterioration with rate of cognitive decline as measured by the difference between the Dementia Rating Scale (DRS) scores obtained at the time of the testing of semantic knowledge (Year 1) and one year later (Year 2), was highly significant (r2 = .84; p < .001). These results suggest that a sensitive measure of the structural deterioration of semantic knowledge may be useful for predicting the rate of progression of cognitive changes in patients with AD. (JINS, 1995, I, 297–303.)
(Received September 14 1994)
(Accepted December 14 1994)
Reprint requests to: David P. Salmon, Department of Neurosciences (0948), ADRC, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0948.