Department of Neurology, Philipps-University Marburg, Marburg, Germany; CMBB - Center for Mind, Brain, and Behavior, Universities of Marburg and Gießen, Marburg, Germany; Department of Neurology, University Hospital Giessen and Marburg, Campus Marburg, Marburg, Germany.
Department of Neurology, Philipps-University Marburg, Marburg, Germany.
Neuropsychologia. 2021 Dec 10;163:108082. doi: 10.1016/j.neuropsychologia.2021.108082. Epub 2021 Oct 30.
The antisaccade task is an established eye-tracking paradigm to explore response inhibition. While many studies showed that antisaccade performance is impaired in Parkinson's disease (PD), the effect of dopaminergic medication is still an area of debate. According to the dopamine overdose hypothesis, intrinsic basal dopamine levels in ventral parts of the striatum determine whether levodopa intake has beneficial or detrimental effects on dopamine-dependent cognitive tasks. The objective of this study was therefore to explore the effect of several disease-related factors on changes in antisaccade performance after levodopa intake in PD. Thirty-five individuals with PD (and 30 healthy controls) performed antisaccades in OFF and ON medication state. Multiple linear regressions were calculated to predict the change in antisaccade latency, directive errors and express saccade rate based on age at PD onset, disease duration, levodopa-equivalent daily dose, motor symptom severity and executive functions. Levodopa intake did not alter antisaccade performance on a group level. However, the effect of levodopa was differentially modulated by age at PD onset and motor symptom severity. Earlier disease onset and milder motor symptoms in OFF medication state were associated with reduced response inhibition capacity after levodopa intake measured as increased express saccade and error rates. Our results indicate that levodopa may have opposing effects on oculomotor response inhibition dependent on the age at PD onset and motor disease severity. Assuming less dopaminergic loss in ventral parts of the striatum in early compared to late onset PD, these findings support the dopamine overdose hypothesis.
反扫视任务是一种成熟的眼动追踪范式，用于探索反应抑制。虽然许多研究表明帕金森病（PD）患者的反扫视表现受损，但多巴胺能药物的作用仍存在争议。根据多巴胺过量假说，纹状体腹侧部分的内在基础多巴胺水平决定了左旋多巴摄入对多巴胺依赖的认知任务是有益还是有害。因此，本研究的目的是探讨几个与疾病相关的因素对 PD 患者左旋多巴摄入后反扫视表现变化的影响。35 名 PD 患者（和 30 名健康对照者）在停用和服用药物状态下进行反扫视。计算了多元线性回归，以根据 PD 发病年龄、疾病持续时间、左旋多巴等效日剂量、运动症状严重程度和执行功能，预测反扫视潜伏期、指令错误和表达性扫视率的变化。左旋多巴摄入并未改变组水平上的反扫视表现。然而，左旋多巴的作用受到 PD 发病年龄和运动症状严重程度的差异调节。在停用药物状态下，发病年龄较早和运动症状较轻与左旋多巴摄入后反应抑制能力降低有关，表现为表达性扫视和错误率增加。我们的结果表明，左旋多巴可能对眼动反应抑制产生相反的影响，这取决于 PD 发病年龄和运动疾病严重程度。假设在早发性 PD 中纹状体腹侧部分的多巴胺能丧失较少，这些发现支持多巴胺过量假说。
