A cross-linguistic study of grammatical morphology in Spanish- and English-speaking agrammatic patients.

To account for cross-linguistic differences in agrammatism, Bates and her colleagues have employed the Competition Model, proposing that the cue validity and cue costs of a grammatical morpheme in a particular language will directly affect how agrammatism is manifested. Using Goodglass et al.'s (1993) Morphosyntax Battery in English and a translated version in Spanish, we analyzed the use of equivalent grammatical structures in production and comprehension by agrammatic speakers of the two languages. Wilcoxon signed-rank tests revealed that the relative order of difficulty in both production and comprehension of various grammatical morphemes was the same for both Spanish- and English-speaking agrammatic patients, with two exceptions (1) the Spanish-speaking agrammatics were relatively better at producing subject-verb agreement, and (2) the Spanish speakers were significantly worse at comprehending both active and passive voice sentences. The Competition Model can explain the performance differences regarding subject-verb agreement and comprehension of active voice sentences, but it cannot account for the differences seen in comprehending passive voice sentences.