Constraining claims about theories of semantic memory: More on unitary versus multiple semantics

In Caramazza, Hillis, Rapp, and Romani (1990) we proposed that the various patterns of impaired performance that have been used to motivate proposals of modality-specific semantics can, instead, be accommodated by an amodal unitary semantics account—the Organised Unitary Content Hypothesis (OUCH). Chertkow, Bub, and Caplan (1992), based on their study of the performance of seven patients with dementia of the Alzheimer’s type, reported data that are supposedly problematic for OUCH. Here we respond by showing that Chertkow and colleagues have misinterpreted our proposal on a number of points and that, in fact, the “problematic” results can be easily accounted for within OUCH. Chertkow et al. made the further claim that their results favour an alternative model of semantic processing, according to which the processing of perceptual-functional semantic information is distinguished from the processing of associative semantic information. We argue here that until Chertkow et al. specify a number of critical features of their proposal it will not be possible to evaluate their claims.