Control and Cross-Domain Mental Computation: Evidence from Language Breakdown

This paper uses the notion of control from programming languages to look at the organization of mental code. Data for the analysis comes principally from language breakdown. The paper first outlines the well known distinction between logic and control in algorithms and argues that the same distinction holds in mental code. Discussion then focuses mainly on control—the management of data flow—and shows that a variety of language disorders affect either the logic component of the mental algorithms for language (e.g., Specific Language Impairment) or the control component (e.g., Williams syndrome and Turner syndrome). A comparative study of the loss of morphology in Williams syndrome and Specific Language Impairment reinforces the logic/control split as an accurate guide to the explanation of linguistic behavior in these disorders. The data, moreover, are not accountable to sheer performance factors, but to the way the disorders disrupt the structure of mental algorithms. The paper closes with a discussion of how control and the management of cross-domain computation fit into recent theories of modular mental architecture and proposals about the explicitness of representations and their availability to working memory.