Substantia nigra integrity correlates with sequential working memory in Parkinson’s disease

Maintaining and manipulating sequential information online is essential for daily activities such as planning. In Parkinson’s disease (PD), deficits in sequential working memory have been associated with altered regional activation and functional connectivity within the basal ganglia. This study demonstrated that the substantia nigra (SN) integrity correlates with basal ganglia dysfunction during sequential working memory. We included 29 patients with PD and 29 healthy controls (HC). We assessed the SN integrity using neuromelanin-sensitive MRI and sequential working memory using functional MRI and a digit ordering task. In this task, participants either recalled a sequence of digits in the original order (‘pure recall’) or rearranged the digits in ascending order and recalled the new sequence (‘reorder & recall’). PD showed smaller SN areas than HC, especially on the left side. Compared to HC, PD showed lower task accuracy, hyper-activation of the subthalamic nucleus, hypo-activati...

在线维持与操作序列信息是规划等日常活动的必要基础。在帕金森病（Parkinson’s disease, PD）中，序列工作记忆的缺损与基底神经节（basal ganglia）内的脑区激活异常及功能连接（functional connectivity）改变密切相关。本研究证实，在执行序列工作记忆任务时，黑质（substantia nigra, SN）的完整性与基底神经节功能障碍存在显著关联。本研究纳入29名PD患者与29名健康对照（healthy controls, HC），采用神经黑色素敏感磁共振成像（neuromelanin-sensitive MRI）评估黑质完整性，并通过功能磁共振成像（functional MRI）与数字排序任务（digit ordering task）评测序列工作记忆能力。在该任务中，受试者需完成两类操作：一是按原始顺序回忆数字序列，即"纯回忆"；二是将数字按升序重排后回忆新序列，即"重排并回忆"。研究结果显示，PD患者的黑质面积小于健康对照，尤以左侧半球更为显著；与健康对照相比，PD患者的任务准确率更低，丘脑底核（subthalamic nucleus）呈现过度激活，且出现激活不足（hypo-activati...）