Person-specific Knowledge and Knowledge of Biological Categories

We report new findings from a neurological case described by Hanley, Young, and Pearson (1989). In the original study, the patient, BD, had impaired biographical knowledge of people which appeared to extend to a general impairment of knowledge of “living things”. In more recent work, we present evidence which confirms Hanley et al.’s finding that BD has impaired person-specific knowledge, but we suggest that this is not associated with a more general impairment to do with knowledge of biological categories. We propose that an artefactual explanation of the original account is more likely based on differences in “age of acquisition” between items from “living” and “nonliving” categories. We conclude that biographical knowledge of people is represented separately from knowledge of biological categories in semantic memory.