Format

Send to

Choose Destination
Mov Disord. 2005 Feb;20(2):238-42.

Short latency afferent inhibition and facilitation in patients with writer's cramp.

Author information

1
Motor Cortex Laboratory, Department of Neurology, J.W. Goethe University, Frankfurt/Main, Germany. k.kessler@em.uni-frankfurt.de

Abstract

Patients with writer's cramp (WC) show abnormalities of sensorimotor integration possibly contributing to their motor deficit. We studied sensorimotor integration by determining short-latency afferent inhibition (SAI) in 12 WC patients and 10 age-matched healthy controls. A conditioning electrical median nerve stimulus was followed 14 to 36 msec later by transcranial magnetic stimulation of the contralateral primary motor cortex, and motor evoked potentials (MEP) were recorded from the relaxed or contracting abductor pollicis brevis muscle (APB). SAI was normal in WC but during APB relaxation SAI was followed by abnormal MEP facilitation, which was absent during APB contraction and in the controls. These findings suggest that somatosensory short-latency inhibitory input into the primary motor cortex is normal in WC, whereas a later excitatory input, which very likely reflects the long-latency reflex II, is exaggerated.

PMID:
15368612
DOI:
10.1002/mds.20295
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center