Cerebellar learning distinguishes inflammatory neuropathy with and without tremor.

Objectives: This study aims to investigate if patients with inflammatory neuropathies and tremor have evidence of dysfunction in the cerebellum and interactions in sensorimotor cortex compared to nontremulous patients and healthy controls.

Methods: A prospective data collection study investigating patients with inflammatory neuropathy and tremor, patients with inflammatory neuropathy without tremor, and healthy controls on a test of cerebellar associative learning (eyeblink classical conditioning), a test of sensorimotor integration (short afferent inhibition), and a test of associative plasticity (paired associative stimulation). We also recorded tremor in the arms using accelerometry and surface EMG.

Results: We found impaired responses to eyeblink classical conditioning and paired associative stimulation in patients with neuropathy and tremor compared with neuropathy patients without tremor and healthy controls. Short afferent inhibition was normal in all groups.

Conclusions: Our data strongly suggest impairment of cerebellar function is linked to the production of tremor in patients with inflammatory neuropathy.