Darley and apraxia of speech in adults

This essay summarises Dr Frederic L. Darley's contributions to the understa nding and treatment of apraxia of speech (AOS). He defined and described th e disorder as it appeared to him in his clinic. He explained it using the p sychological and neurological models and vocabularies of his day. His stude nts, and other interested clinical investigators, worked to confirm, expand , and in some cases, revise portions of his original contribution. Opponent s tried to recast his notions altogether. The contributions of both, includ ing the motor programming and linguistic models they used and perceptual, a coustic, and physiologic data they collected, have formed part of our moder n understanding of AOS. Improved evaluation and conceptually-based treatmen ts are among the best parts of Fred's legacy.