Abstract
Controversy exists as to whether semantic disruption in Alzheimer's disease (AD) systematically impairs the naming of living things. Moreover, little is known about performance across more specific subcategories. We investigated picture naming in 28 AD patients and 24 controls. To deal with nonnormal distributions, we created 1,000 bootstrap hierarchical regressions and determined which variables (the “nuisance” variables familiarity, word frequency, age of acquisition and visual complexity; category; and control naming) best predicted AD patient naming. Nuisance variables combined, control naming, and category uniquely accounted for 39%, 36%, and 3% of patient naming variance, respectively. Finally, analysis of the AD naming profile across the 10 subcategories mirrored that of controls. Taken together, these findings indicate that while AD naming is, of course, quantitatively worse than that of controls, it does not qualitatively differ—that is, it is an exaggerated normal profile.
The authors are grateful to Peter Simmons, Hema Ananth, and all participants in the study. We also acknowledge the contributions of three reviewers.
Notes
1Unfortunately information about length of education was not available for patients or controls.