[Vocal and respiratory diadochokinesia in Friedreich's ataxia. Neuropathological correlations]

Acoustic analysis of unvoiced diadochokinetic respiratory cycles helped identify two kinds of impairments in ten Friedreich's ataxia patients. Four patients manifested moderate problems maintaining regularity in the repetition of unvoiced respiratory cycles, and also showed moderate articulatory dysarthric problems in a syllabic repetition task. Six patients had severe respiratory insufficiency in the inspiration/expiration repetition task, and exhibited very important amplitude and fundamental frequency disturbances and a much slower rate of syllabic utterances. This respiratory insufficiency and aggravated speech disorders were linked to presence of pontine and medullary atrophy, sites comprising the respiratory centers of the brain stem.