Category-specific naming impairments? Yes

Recently, Stewart, Parkin, and Hunkin (1992) have questioned previously reported cases of selective damage in processing items from categories of animate objects, arguing that there has been a lack of adequate control for visual familiarity, visual complexity, and name frequency of the stimuli employed. When re-testing Michelangelo (see Sartori & Job, 1988), one of the patients cited by Stewart et al. (1992), with a set of materials matched on all three factors, the asymmetry in naming animal and artefact items still remains. An analogous pattern is obtained when--in addition to such factors--the visual similarity within the sub-sets of animals and artefacts is taken into account. These results constitute empirical evidence for category-specific impairments and cannot be interpreted as being due to isolated or conjoint effects of visual familiarity, visual complexity, or name frequency.