L-DOPA improves visuo-motor coordination in stable Parkinson's disease patients.

The visuo-motor coordination of 26 stable, treated, Parkinson's disease (PD) patients with average Hoehn and Yahr rating of 1.75+/-0.6, was assessed by use of several tracing and tracking tests before and 30min after ingestion of the mid-day levodopa (L-DOPA) dose. Significant improvement was found in all aspects of visuo-motor coordination 30min after drug intake. This included the ability to control the direction and velocity of hand-movement, and the capacity to persist in tracking. A subgroup of 12 patients was tested 30min and 1h after L-DOPA intake. A continuing (but small) improvement in directional and velocity control could still be seen an hour after drug intake, while tracking persistence remained unchanged with respect to the preceding test. We conclude that changes in executional capabilities can be documented in "stable" PD patients, consequent to L-DOPA intake, when high-level skills, such as visuo-motor coordination, are tested.