Cerebellar Disorders
The neurons in the ventrolateral medulla that generate cough and
breathing patterns interact with neural networks in the
cerebellum-rostral interposed nucleus, the rostral fastigial nucleus,
and the infra-cerebellar nucleus. Therefore, a dramatic reduction in
cough frequency is observed after cerebellectomy or lesion of the
interposed nucleus (15). In cerebellar neurodegenerative diseases, there
is a reduction in the frequency of cough episodes that coincides with
cerebellar atrophy. However, in a rare form of autosomal dominant
cerebellar ataxia (spinocerebellar ataxia type-5), episodes of spasmodic
cough begin 10 to 30 years earlier than the onset of ataxia. It may also
be associated with spasmodic dysphonia and tremor. Both spasmodic cough
and dysphonia may be caused by laryngeal hyperreactivity and vagal
dysfunction. These coughing episodes could be considered reliable
markers of familial neurodegenerative disease if there is a previously
diagnosed case (16).