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M C Linebarger

Publications and source records attributed to M C Linebarger.

4 recordsLinked to original sources
PubMed2000

Grammatical encoding in aphasia: evidence from a "processing prosthesis".

Agrammatic aphasia is characterized by severely reduced grammatical structure in spoken and written language, often accompanied by apparent insensitivity to grammatical structure in comprehension. Does agrammatism represent loss of linguistic competence or rather performance factors such as memory or resource limitations? A considerable body of evidence supports the latter hypothesis in the domain of comprehension. Here we present the first strong evidence for the performance hypothesis in the domain of production: an augmentative communication system that markedly increases the grammatical structure of agrammatic speech while providing no linguistic information, functioning merely to reduce on-line processing demands.

Aphasia, Broca↗
PubMed1998

Semantic influences on thematic role assignment: evidence from normals and aphasics.

We report two studies that examine the role of semantic influences in the assignment of thematic roles. Semantic factors were manipulated by contrasting sentences in which one noun argument was a plausible filler of only one thematic role (e.g., the painting in The artist disliked the painting) with sentences in which both noun arguments were plausible fillers of both thematic roles (e.g., The robin ate the insect). Subjects were required to make plausibility judgments to sentences presented auditorily. Experiment 1 examined RTs of normal subjects on the plausibility judgment task. In Experiment 2, the same sentences were presented to aphasic patients identified as "asyntactic" comprehenders. In Experiment 1, RTs were speeded by semantic constraints on thematic assignment, particularly when the role-constrained NP occurred early in the sentence (as in The painting was disliked by the artist). The aphasic performance patterns in Experiment 2 paralleled those of normal subjects, but in greatly exaggerated fashion. The patients exhibited high error rates on sentences where semantic constraints conflicted with the syntactically based assignments, even on sentences with canonical (S-V-O) word order (e.g., #The deer shot the hunter).

Aged↗
PubMed1995

Agrammatism as evidence about grammar.

A variety of experimental paradigms has yielded surprisingly fine-grained evidence about the kinds of syntactic information to which agrammatic aphasics are sensitive. This paper contrasts three accounts of agrammatism which draw quite different conclusions about the implications of this disorder for normal function: the chain-disruption, trade-off, and mapping hypotheses. Counterarguments to the chain disruption and trade-off hypotheses are presented, and it is argued that agrammatism provides considerable support for the modularity of syntax but provides no evidence more specific than that regarding the psychological reality of government binding theory vis-à-vis other current theories of grammar.

Brain↗