Hold your horses: impulsivity, deep brain stimulation, and medication in parkinsonism.
Deep brain stimulation (DBS) of the subthalamic nucleus markedly improves the motor symptoms of Parkinson's disease, but causes cognitive side effects such as impulsivity. We showed that DBS selectively interferes with the normal ability to slow down when faced with decision conflict. While on DBS, patients actually sped up their decisions under high-conflict conditions. This form of impulsivity was not affected by dopaminergic medication status. Instead, medication impaired patients' ability to learn from negative decision outcomes. These findings implicate independent mechanisms leading to impulsivity in treated Parkinson's patients and were predicted by a single neurocomputational model of the basal ganglia.
Frank
Michael J
MJ
Department of Psychology and Program in Neuroscience, University of Arizona, Tucson, AZ 85721, USA. mfrank@u.arizona.edu
Samanta
Johan
J
Moustafa
Ahmed A
AA
Sherman
Scott J
SJ
D000368:Aged; D000978:Antiparkinson Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D001479:Basal Ganglia / Q000502:physiology; D003220:Conflict, Psychological; D003657:Decision Making; D046690:Deep Brain Stimulation / Q000009:adverse effects*; D015259:Dopamine Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000209:etiology*; D007858:Learning; D007980:Levodopa / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D016571:Neural Networks, Computer; D010300:Parkinson Disease / Q000503:physiopathology / Q000523:psychology* / Q000628:therapy*; D011930:Reaction Time; D012054:Reinforcement, Psychology; D020531:Subthalamic Nucleus / Q000502:physiology*
D000978:Antiparkinson Agents; D015259:Dopamine Agents; D007980:Levodopa