Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, USA.
Department of Biomedical Engineering, University of Florida, Gainesville, USA.
J Neurol Neurosurg Psychiatry. 2017 Nov;88(11):968-970. doi: 10.1136/jnnp-2016-315325. Epub 2017 Aug 19.
A significant subset of patients with Parkinson's disease (PD) suffer from impulse control disorders (ICDs). A hallmark feature of many ICDs is the pursuit of rewarding behaviours despite negative consequences. Recent evidence implicates the subthalamic nucleus (STN) and globus pallidus internus (GPi) in reward and punishment processing, and deep brain stimulation (DBS) of these structures has been associated with changes in ICD symptoms.
We tested the hypothesis that in patients with PD diagnosed with ICD, neurons in the STN and GPi would be more responsive to reward-related stimuli and less responsive to loss-related stimuli. We studied a cohort of 43 patients with PD (12 with an ICD and 31 without) undergoing DBS electrode placement surgery. Patients performed a behavioural task in which their action choices were motivated by the potential for either a monetary reward or a monetary loss. During task performance, the activity of individual neurons was recorded in either the STN (n=100) or the GPi (n=100).
The presence of an ICD was associated with significantly greater proportions of reward responsive neurons (p<0.01) and significantly lower proportions of loss responsive neurons (p<0.05) in the STN, but not in the GPi.
These findings provide further evidence of STN involvement in impulsive behaviour in the PD population.
帕金森病（PD）患者中有相当一部分患有冲动控制障碍（ICD）。许多 ICD 的一个显著特征是尽管有负面后果，但仍追求奖励行为。最近的证据表明，底丘脑核（STN）和苍白球 internus（GPi）参与了奖励和惩罚处理，这些结构的深部脑刺激（DBS）与 ICD 症状的变化有关。
我们测试了这样一个假设，即在被诊断患有 ICD 的 PD 患者中，STN 和 GPi 中的神经元对奖励相关刺激的反应更敏感，对损失相关刺激的反应更不敏感。我们研究了一组 43 名接受 DBS 电极放置手术的 PD 患者（12 名患有 ICD，31 名没有）。患者执行一项行为任务，他们的行动选择受到获得货币奖励或货币损失的可能性的驱动。在任务执行过程中，记录了个体神经元在 STN（n=100）或 GPi（n=100）中的活动。
ICD 的存在与 STN 中反应奖励的神经元比例显著增加（p<0.01）和反应损失的神经元比例显著降低（p<0.05）有关，但在 GPi 中没有。
这些发现为 PD 人群中 STN 参与冲动行为提供了进一步的证据。
