Division of Brain, Imaging and Behaviorur-Systems Neuroscience, Toronto Western Research Institute and Hospital, UHN, University of Toronto, Toronto, Ontario, Canada.
Mov Disord. 2011 Feb 1;26(2):225-33. doi: 10.1002/mds.23480. Epub 2011 Jan 31.
Pathological gambling may occur in Parkinson's disease (PD) as a complication of dopaminergic therapy. Neuroimaging studies have suggested an abnormal dopamine transmission within the reward system, but the changes in the neural network characterizing PD patients with pathological gambling have never been investigated.
Thirty PD patients (15 with active gambling and 15 matched controls, on-medication) and 15 healthy subjects underwent brain perfusion single photon emission tomography at rest. The severity of gambling was assessed using the South Oaks Gambling Scale. Covariance analysis was applied to identify brain regions whose activity was associated with gambling severity. These regions were used as volume-of-interest to identify functionally interconnected areas using voxel-wise covariance analysis. A path model was defined by means of effective connectivity analysis within the Structural Equation Modeling framework.
Gambling severity in PD was associated with a dysfunction of the brain network implicated in decision making, risk processing, and response inhibition, including the ventrolateral prefrontal cortex, anterior (ACC) and posterior cingulate cortex, medial prefrontal cortex, insula and striatum. PD gamblers showed a disconnection between the ACC and the striatum, while this interaction was very robust in both control groups.
ACC-striatal disconnection may underlie a specific impairment of shifting behaviors after negative outcomes, possibly explaining why PD gamblers use to perseverate into risktaking behaviors despite self-destructive consequences.
病理性赌博可能是帕金森病（PD）患者多巴胺治疗的一种并发症。神经影像学研究表明，在奖励系统内多巴胺传递异常，但 PD 伴病理性赌博患者的神经网络变化从未被研究过。
30 名 PD 患者（15 名有活动性赌博，15 名匹配的对照，药物治疗）和 15 名健康受试者在休息时进行脑灌注单光子发射断层扫描。赌博严重程度使用 South Oaks 赌博量表进行评估。协方差分析用于识别与赌博严重程度相关的大脑活动区域。这些区域被用作体素协方差分析来识别功能上相互连接的区域的兴趣区。通过结构方程建模框架内的有效连通性分析来定义路径模型。
PD 患者的赌博严重程度与参与决策、风险处理和反应抑制的大脑网络功能障碍有关，包括腹外侧前额叶皮层、前扣带皮层（ACC）和后扣带皮层、内侧前额叶皮层、岛叶和纹状体。PD 赌徒在 ACC 和纹状体之间表现出脱节，而在两个对照组中，这种相互作用都非常稳健。
ACC-纹状体脱节可能是负面结果后转移行为的特定损伤的基础，这可能解释了为什么 PD 赌徒尽管有自我毁灭的后果，但仍会坚持冒险行为。
