Dynamic aphasia and the generation of language

Severely reduced propositional speech in the context of intactnominal language skills (i.e., repetition, naming, comprehension, andreading) is the hallmark ofdynamic aphasia(Luria, 1970). Recentevidence suggests there may be different types of dynamic aphasia assome patients do not produce any response on verbal generationtasks, whilst others are able to perform normally on verbal genera-tion tasks. For example, Robinson and colleagues (Robinson, Blair,& Cipolotti, 1998; Robinson, Shallice, & Cipolotti, 2004) reportedtwo dynamic aphasics who failed to produce a verbal response whenmany verbal response options were activated by a stimulus, but notwhen a dominant response was available. By contrast, a dynamicaphasic patient reported by Snowden, Griffiths, and Neary (1996)was able to produce sentences and words on specific verbal gener-ation tasks. We report a dynamic aphasic patient (KAS) who, sim-ilarly to the patient reported by Snowden et al. performed flawlesslyon all verbal generation tasks, despite almost abolished propositionalspeech.