What do category-specific semantic deficits tell us about the representation of lexical concepts?

A reassessment of category-specific semantic deficits in light of their contribution to a theory of the representation of lexical concepts is proposed. Two theories are examined: one, held by the majority of researchers in the field, claims that concepts are represented by sets of features; another, in contrast, claims that concepts are atomic representations. An analysis of category-specific semantic deficits in terms of inferential relations (of the meaning-postulates type) between atomic concepts is elaborated. It is argued that this theory can better account for the pattern of performance exhibited by patients with semantic deficits.