Clinicoanatomic studies in dysarthria: Review, critique, and directions for research

More than 30 years ago, Darley, Aronson, and Brown (1969) proposed clinicoa natomic correlations for seven perceptual types of dysarthria. These correl ations have not been systematically re-examined even though imaging technol ogies developed in recent years provide the means to do so. This review con siders data from published imaging studies as well as data from selected me dical interventions to evaluate the current state of knowledge that relates lesion site to the nature of a speech disturbance. Although the extant dat a are not sufficient to allow a complete evaluation of the seven types of d ysarthria described by Darley et al., relevant information has been reporte d on lesions of the pyramidal pathway, extrapyramidal pathway, and cerebell um. In general, the results are best explained by an equivalence mode of br ain-behavior relationship in which a type of dysarthria is associated with a lesion in one of two or more brain structures. Criteria also are proposed for future studies of clinicoanatomic relationships in neurogenic communic ation disorders.