title: Handwriting in patients with Parkinson disease: effect of L-dopa and stimulation of the sub-thalamic nucleus on motor anticipation.
abstract: The present research focused on how patients with Parkinson's disease (PD) produce handwriting sequences. PD patients who were on/off medication or deep brain stimulation treatments had to write lll and lln trigrams. We evaluated their ability to anticipate on-line the last letter in the trigram. The results revealed that in PD patients, contrary to healthy participants, the percentage of time taken by the down-stroke of the second l did not vary as a function of the spatial constraints of the following letter (l or n). In other words, the handwriting of the PD patients did not exhibit any sign of motor anticipation. However, under treatment, PD patients exhibited similar results to healthy participants despite no improvement in movement variability. Taken together these results do not seem consistent with the hypothesis that PD patients do not anticipate future movements because of their movement variability. They are more in agreement with theories that postulate that PD patients have a general deficit in the parallel processing of the components of a motor sequence.
authors.affiliation: Laboratoire de Psychologie et NeuroCognition, CNRS UMR 5105, BP47, 38040 Grenoble Cedex 9, France. christel.bidet@univ-poitiers.fr
authors.forename: Christel
authors.initials: C
authors.lastname: Bidet-Ildei
authors.forename: Pierre
authors.initials: P
authors.lastname: Pollak
authors.forename: Sonia
authors.initials: S
authors.lastname: Kandel
authors.forename: Valérie
authors.initials: V
authors.lastname: Fraix
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Orliaguet
mesh_terms: D000328:Adult; D059031:Anticipation, Psychological / Q000187:drug effects / Q000502:physiology; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D001288:Attention / Q000187:drug effects / Q000502:physiology; D003196:Computer Graphics; D046690:Deep Brain Stimulation; D005260:Female; D006236:Handwriting; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination / Q000187:drug effects; D010300:Parkinson Disease / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012016:Reference Values; D020531:Subthalamic Nucleus / Q000502:physiology*
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa