Grodzinsky interprets linguistic differences between agrammatic comprehension and production symptoms as supporting the hypothesis that the mechanisms underlying grammatical encoding (sentence formulation) and grammatical decoding (syntactic parsing) are at least partially distinct. This inference is shown to be premature. A range of experimentally established similarities between the encoding and decoding processes is highlighted, testifying to the viability of the hypothesis that receptive and productive syntactic tasks are performed by the same syntactic processor.

Neuropsychological results are increasingly cited in cognitive theories although their methodology has been severely criticised. The book argues for an eclectic approach but particularly stresses the use of single-case studies. A range of potential artifacts exists when inferences are made from such studies to the organisation of normal function – for example, resource differences among tasks, premorbid individual differences, and reorganisation of function. The use of “strong” and “classical” dissociations minimises potential artifacts. The theoretical convergence between findings from fields where (...) cognitive neuropsychology is well developed and those from the normal literature strongly suggests that the potential artifacts are not critical. The fields examined in detail in this respect are short-term memory, reading, writing, the organisation of input and output speech systems, and visual perception. Functional dissociation data suggest that not only are input systems organised modularly, but so are central systems. This conclusion is supported by findings on impairment of knowledge, visual attention, supervisory functions, memory, and consciousness. (shrink)