Occasional deep involuntary sighs may occur in multiple system atrophy. Sighing is also a feature, along with yawning, of the early (diencephalic) stage of central herniation of the brainstem with an otherwise normal respiratory pattern. Sudden inspiratory or expiratory sighs are said to be a feature of the hyperkinetic choreiform dysarthria characteristically seen in choreiform disorders, such as Huntington’s disease.
Quinn N. Multiple system atrophy. In: Marsden CD, Fahn S (eds.).
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