Opportunities to say 'yes': rare speech automatisms in a case of progressive nonfluent aphasia and apraxia.

We describe the investigation of speech automatisms in a man with progressive nonfluent aphasia and apraxias. Occurrence of the automatisms yes and right, were analysed across a range of speech tasks varying in length, propositionality, lexical and articulatory complexity, whether tasks engaged internal generation or external triggering and articulatory distortions, and while completing pantomimes/gestures. No differences were found in occurrence across most tasks but there was a significant interaction between automatism production and apraxic speech errors and during limb praxic tasks, suggesting that production of the automatism was unrelated to linguistic or lexical variables, but was related to the presence of speech apraxia coupled with disinhibition.