Bradykinesia is defined as a “complex” of motor alterations including decreased movement amplitude and/or speed and tendency to reduce them with movement repetition (sequence effect). This study aimed at investigating the neural and kinematic correlates of bradykinesia during hand-tapping in people with Parkinson’s disease (pwPD) relative to healthy controls. Twenty-five pwPD and 25 age- and sex-matched healthy controls underwent brain functional MRI (fMRI) during a hand-tapping task: subjects alternatively opened and closed their right hand as fully and quickly as possible. Hand-tapping kinematic parameters were objectively measured during the fMRI task using an optical fibre glove. During the fMRI task, pwPD showed reduced hand-tapping amplitude (hypokinesia) and a greater sequence effect. PwPD relative to healthy controls showed a reduced activity of fronto-parietal areas, middle cingulum/supplementary motor area (SMA), parahippocampus, pallidum/thalamus and motor cerebellar areas. Moreover, pwPD showed an increased activity of brain cognitive areas such as superior temporal gyrus, posterior cingulum, and cerebellum crus I. The decreased activity of cerebellum IV–V–VI, vermis IV–V, inferior frontal gyrus, and cingulum/SMA correlated with hypokinesia and with the sequence effect. Interestingly, a reduced activity of areas involved in motor planning and timing correlated both with hypokinesia and with the sequence effect in pwPD. This study has the major strength of collecting objective motor parameters and brain activity simultaneously, providing a unique opportunity to investigate the neural correlates of the “bradykinesia complex”.

运动迟缓被定义为运动改变的“复杂”，包括运动幅度和/或速度的降低以及随着运动重复而减少的趋势（序列效应）。本研究旨在调查帕金森病 (pwPD) 患者相对于健康对照者在手敲击过程中运动迟缓的神经和运动学相关性。 25 名残疾人士和 25 名年龄和性别匹配的健康对照者在手敲击任务中接受了脑功能 MRI (fMRI)：受试者尽可能完全、快速地交替打开和关闭右手。在功能磁共振成像任务期间，使用光纤手套客观地测量了手敲击运动参数。在功能磁共振成像任务期间，pwPD 显示出手敲击幅度降低（运动功能减退）和更大的序列效应。与健康对照相比，PwPD 患者的额顶叶区、中扣带回/辅助运动区 (SMA)、海马旁回、苍白球/丘脑和运动小脑区的活动减少。此外，pwPD 显示大脑认知区域的活动增加，例如颞上回、扣带回后部和小脑小腿 I。小脑 IV-V-VI、蚓部 IV-V、额下回和扣带回/SMA 相关的活动减少具有运动功能减退和序列效应。有趣的是，参与运动计划和时间安排的区域活动减少与运动功能减退和 pwPD 中的序列效应相关。这项研究的主要优势是同时收集客观运动参数和大脑活动，为研究“运动迟缓复合体”的神经相关性提供了独特的机会。