The production of grammatical and lexical determiners in Broca's aphasia

Determiner production is a testing ground for theories of Broca's aphasia and agrammatic speech. On one type of theory, determiner production is impaired in so far as determiners are grammatical items. On another type of theory, determiner production is impaired because determiners depend on verbs for case-assignment. These two types of theories are mutually compatible, but in recent years, research on determiner production has focused on the second type. In order to test the first type, an experiment was carried out which contrasted the production of Danish grammatical determiners (indefinite articles) and lexical ones (numerals) in five speakers diagnosed with Broca's aphasia and four non-brain-damaged controls. The results strongly support the first type of theories: (1) in agrammatic speech, only grammatical determiners were omitted to an extent which differs from omission rates in the speech of the controls; (2) substitutions of grammatical agreement markers were found only in agrammatic speech.