Related Experiment Video
Updated: May 31, 2026

Intracortical Inhibition Within the Primary Motor Cortex Can Be Modulated by Changing the Focus of Attention
Published on: September 11, 2017
Extreme task specificity in writer's cramp
Ejaz A Shamim1, Jason Chu, Linda H Scheider
1Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA. shamime@mail.nih.gov
Background:
Focal hand dystonia may be task specific, as is the case with writer's cramp. In early stages, task specificity can be so specific that it may be mistaken for a psychogenic movement disorder.
Methods:
We describe 4 patients who showed extreme task specificity in writer's cramp. They initially only had problems writing either a single letter or number. Although they were largely thought to be psychogenic, they progressed to typical writer's cramp.
Conclusions:
Early recognition of this condition may provide an opportunity for early initiation of treatment.
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