title: Differential effects of subthalamic nucleus stimulation in advanced Parkinson disease on reaction time performance.
abstract: The aim of the present study was to assess the effect of bilateral subthalamic nucleus (STN) stimulation and dopaminergic medication on speed of mental processing and motor function. Thirty-nine patients suffering from advanced Parkinson disease (PD) were operated on. Motor function and reaction time (RT) performance [simple RT (SRT) and complex RT (CRT)] were evaluated under four experimental conditions with stimulation (stim) and medication (med) on and off: stim-on/med-on, stim-on/med-off, stim-off/med-off and stim-off/med-on. In the last condition, the patients received either low medication (usual dose) or high medication (suprathreshold dose). STN stimulation improved the motor performance in the SRT and CRT tasks. Furthermore, STN deep brain stimulation (DBS) also improved response preparation as shown by the significant improvement of the RT performance in the SRT task. This effect of STN DBS on the RT performance in the SRT task was greater as compared with the CRT task. This is due to the more complex information processing that is required in the CRT task as compared to the SRT task. These data suggest that treatment of STN hyperactivity by DBS improves motor function, confirming earlier reports, but has a differential effect on cognitive functions. The STN seems to be an important modulator of cognitive processing and STN DBS can differentially affect motor and associative circuits.
authors.affiliation: Departments of Neurosurgery and Cellular Neuroscience, European Graduate School of Neuroscience (EURON), University Hospital Maastricht, Po Box 5800, 6202, AZ, Maastricht, The Netherlands. y.temel@np.unimaas.nl
authors.forename: Yasin
authors.initials: Y
authors.lastname: Temel
authors.forename: Arjan
authors.initials: A
authors.lastname: Blokland
authors.forename: Linda
authors.initials: L
authors.lastname: Ackermans
authors.forename: Peter
authors.initials: P
authors.lastname: Boon
authors.forename: Vivianne H J M
authors.initials: VH
authors.lastname: van Kranen-Mastenbroek
authors.forename: E A M
authors.initials: EA
authors.lastname: Beuls
authors.forename: Geert H
authors.initials: GH
authors.lastname: Spincemaille
authors.forename: Veerle
authors.initials: V
authors.lastname: Visser-Vandewalle
mesh_terms: D000203:Activities of Daily Living; D000704:Analysis of Variance; D000978:Antiparkinson Agents / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004599:Electric Stimulation Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D010300:Parkinson Disease / Q000628:therapy*; D011930:Reaction Time / Q000502:physiology*; D012189:Retrospective Studies; D020531:Subthalamic Nucleus / Q000502:physiology*; D013647:Task Performance and Analysis
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa