Darley and apraxia of speech in adults

This essay summarises Dr Frederic L. Darley's contributions to the understanding and treatment of apraxia of speech (AOS). He defined and described the disorder as it appeared to him in his clinic. He explained it using the psychological and neurological models and vocabularies of his day. His students, and other interested clinical investigators, worked to confirm, expand, and in some cases, revise portions of his original contribution. Opponents tried to recast his notions altogether. The contributions of both, including the motor programming and linguistic models they used and perceptual, acoustic, and physiologic data they collected, have formed part of our modern understanding of AOS. Improved evaluation and conceptually-based treatments are among the best parts of Fred's legacy.