table_1_Impulsivity in Parkinson’s Disease Is Associated With Alterations in Affective and Sensorimotor Striatal Networks.docx

A subset of patients with Parkinson’s disease (PD) experiences problems with impulse control, characterized by a loss of voluntary control over impulses, drives, or temptations regarding excessive hedonic behavior. The present study aimed to better understand the neural basis of such impulse control disorders (ICDs) in PD. We collected resting-state functional connectivity and structural MRI data from 21 PD patients with ICDs and 30 patients without such disorders. To assess impulsivity, all patients completed the Barratt Impulsiveness Scale and performed an information-gathering task. MRI results demonstrated substantial differences in neural characteristics between PD patients with and without ICDs. Results showed that impulsivity was linked to alterations in affective basal ganglia circuitries. Specifically, reduced frontal–striatal connectivity and GPe volume were associated with more impulsivity. We suggest that these changes affect decision making and result in a preference for risky or inappropriate actions. Results further showed that impulsivity was linked to alterations in sensorimotor striatal networks. Enhanced connectivity within this network and larger putamen volume were associated with more impulsivity. We propose that these changes affect sensorimotor processing such that patients have a greater propensity to act. Our findings suggest that the two mechanisms jointly contribute to impulsive behaviors in PD.

部分帕金森病（Parkinson’s Disease, PD）患者会出现冲动控制问题，其特征为对过度享乐性行为相关的冲动、驱力或诱惑丧失自主控制能力。本研究旨在更深入地阐明帕金森病患者此类冲动控制障碍（impulse control disorders, ICDs）的神经生物学基础。
我们从21名合并冲动控制障碍的帕金森病患者以及30名无此类障碍的帕金森病患者中，采集了静息态功能连接（resting-state functional connectivity）与结构磁共振成像（structural MRI）数据。为评估冲动性水平，所有受试者均完成了巴瑞特冲动量表（Barratt Impulsiveness Scale）测评，并完成了一项信息收集任务。
磁共振成像结果显示，合并与未合并冲动控制障碍的帕金森病患者在神经特征上存在显著差异。研究发现，冲动性与情感性基底神经节环路的改变存在关联：具体而言，额-纹状体连接减弱以及外侧苍白球（external segment of the globus pallidus, GPe）体积缩小，与更高的冲动性水平相关。我们推测，此类改变会影响决策过程，进而导致患者偏好风险较高或不适宜的行为。
研究结果还显示，冲动性与感觉运动纹状体网络的改变存在关联：该网络内部连接增强以及壳核（putamen）体积增大，与更高的冲动性水平相关。我们提出，此类改变会影响感觉运动加工过程，使得患者更易产生冲动行为。本研究结果表明，这两种机制共同参与了帕金森病患者的冲动行为表现。