Area of Neuroscience, SISSA, via Bonomea 265, 34136, Trieste, Italy.
Azienda Ospedaliero-Universitaria "Ospedali Riuniti" of Trieste, Strada di Fiume 447, 34149, Trieste, Italy.
J Neurol. 2019 May;266(5):1113-1119. doi: 10.1007/s00415-019-09240-0. Epub 2019 Feb 14.
Although deep brain stimulation of the subthalamic nucleus is an effective surgical treatment for Parkinson's disease, it may expose patients to non-motor side effects such as increased impulsivity and changes in decision-making behavior. Even if several studies have shown that stimulation of the subthalamic nucleus increases the incentive salience of food rewards in both humans and animals, temporal discounting for food rewards has never been investigated in patients who underwent STN-DBS. In this study, we measured inter-temporal choice after STN-DBS, using both primary and secondary rewards. In particular, PD patients who underwent STN-DBS (in ON medication/ON stimulation), PD patients without STN-DBS (in ON medication) and healthy matched controls (C) performed three temporal discounting tasks with food (primary reward), money and discount vouchers (secondary rewards). Participants performed also neuropsychological tests assessing memory and executive functions. Our results show that STN-DBS patients and PD without DBS behave as healthy controls. Even PD patients who after DBS experienced weight gain and/or eating alterations did not show an increased temporal discounting for food rewards. Interestingly, patients taking a higher dosage of dopaminergic medications, fewer years from DBS surgery and, unexpectedly, with better episodic memory were also those who discounted rewards more. In conclusion, this study shows that STN-DBS does not affect temporal discounting of primary and secondary rewards. Furthermore, by revealing interesting correlations between clinical measures and temporal discounting, it also shed light on the clinical outcomes that follow STN-DBS in patients with PD.
虽然丘脑底核深部脑刺激是治疗帕金森病的有效手术方法，但它可能使患者暴露于非运动副作用，如冲动增加和决策行为改变。尽管有几项研究表明，刺激丘脑底核会增加人类和动物的食物奖励的激励显著性，但从未在接受 STN-DBS 的患者中研究过食物奖励的时间折扣。在这项研究中，我们使用主要和次要奖励来测量 STN-DBS 后的跨时选择。具体来说，接受 STN-DBS 的 PD 患者（药物治疗/刺激开启）、未接受 STN-DBS 的 PD 患者（药物治疗开启）和健康匹配对照（C）进行了三项食物（主要奖励）、金钱和折扣券（次要奖励）的时间折扣任务。参与者还进行了评估记忆和执行功能的神经心理学测试。我们的结果表明，STN-DBS 患者和未接受 DBS 的 PD 患者的行为与健康对照相同。即使在 DBS 后经历体重增加和/或饮食改变的 PD 患者也没有表现出对食物奖励的时间折扣增加。有趣的是，服用更高剂量多巴胺能药物、接受 DBS 手术时间较短、出乎意料的是，情景记忆更好的患者也会更多地折现奖励。总之，这项研究表明，STN-DBS 不会影响主要和次要奖励的时间折扣。此外，通过揭示临床测量与时间折扣之间的有趣相关性，它还阐明了接受 STN-DBS 的 PD 患者的临床结果。
