Training sentence production in agrammatism: implications for normal and disordered language

Area of Science:

• Linguistics
• Neuroscience
• Psychology

Background:

• Agrammatic aphasia, often associated with Broca's area damage, causes significant deficits in sentence production and comprehension.
• Individuals with aphasia struggle with complex sentences involving non-canonical word order, particularly those requiring movement operations.

Purpose of the Study:

• To investigate the effectiveness of targeted intervention for sentence production deficits in agrammatic aphasia.
• To examine sentence production patterns and generalization following training on specific syntactic structures.

Main Methods:

• Employed a single-subject experimental research paradigm with aphasic individuals.
• Utilized Chomsky's Government Binding Theory and psycholinguistic findings to design sentence stimuli and intervention.
• Trained subjects on sentences involving NP-movement (passives) and WH-movement (wh-questions, object clefts).

Main Results:

• All subjects demonstrated improved sentence production abilities after the intervention.
• Significant generalization of production was observed for untrained WH-movement structures, but not for NP-movement structures.
• Generalization of wh-question production varied, with some subjects showing generalization only when wh-morphemes were targeted, suggesting multiple processing steps.

Conclusions:

• Targeted intervention can effectively improve sentence production in agrammatic aphasia.
• The findings provide insights into the nature of sentence production deficits and the underlying mechanisms of normal sentence production.
• Recovery data, controlled for lexical and syntactic properties, are crucial for understanding aphasia and sentence processing.