A Computer Model of the Temporal Course of Agrammatic Sentence Understanding: The Effects of Variation in Severity and Sentence Complexity

In this article, we present SYNCHRON, o computer model of Kolk and van Grunsven’s (1985) hypothesis of ogrommotic comprehension deficits. According to this hypothesis, porsing foils in ogrommotic aphasics since syntactic representational elements thot need to be active simultaneously ore often not cooctive because of disturbances in timing due to brain damage. SYNCHRON hos been especially designed to account for two neglected aspects of agrammotic comprehension: degrees of severity and the sentence-complexity effect. We report on attempt to simulate data from two sentence-picture-matching studies in which o qualitatively similar sentence-complexity effect was found ot two different overage levels of severity. This pottern wos reproduced when the timing disorder was assumed to affect syntactic phrasal categories, but not when it wos assumed to affect function-word categories. When phrasal categories were involved, fit WQS not much affected, whether the damage wos assumed to slow down the time for on element to be retrieved, or to decrease the time for on element to remain avoiloble.