Size matters: A study on naming and size knowledge in dementia of the Alzheimer type

Abstract

Category-specificity was longitudinally studied over a period of 12 months in seven Alzheimer disease patients, with two semantic tasks differing with respect to verbal processing demands: picture naming and a size ordering task. Items from each task were matched on all cognitive and psycholinguistic variables known to differ across domains (living–nonliving). Naming performance of patients was poorer than that of normal controls. Regarding category-specific effects, while naming performance of patients was parallel to that of normal controls, patients' performance with the size ordering task revealed a different scaling of living things while that of nonliving things mirrored performance of normal controls. This suggests that caution is needed when the picture naming task is exclusively used to document category-specific effects.

Keywords:

• Size ordering
• Category-specificity
• Naming picture
• Alzheimer's disease
• Longitudinal study

Acknowledgments

I wish to thank I.N.S. and John L. Woodard for their help. We also thank Holly A. Tuokko and James H. Waters who kindly reviewed an earlier English version of this work, as well as for their valuable comments. I also wish to thank two anonymous reviewers for their helpful comments to an earlier version of this manuscript.

Notes

¹Similarly to McRae and Cree (2002), we use the expression ‘domain’ to refer to living and nonliving things and the term ‘subcategory’ to refer to mid-level categories (e.g., animals and furniture). However, we use ‘category-specific’, ‘category-specificity’ and ‘category-specific effects’ generically.

²Words in italic are added by the author.