Effects of Parkinson's disease on optic flow perception for heading direction during navigation.
Effects of Parkinson's disease on optic flow perception for heading direction during navigation.
复制标题
帕金森病对导航过程中前进方向光流感知的影响。
DOI：
10.1007/s00221-014-3853-9
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发表时间：
2014
影响因子：
2
通讯作者：
Cronin-Golomb,Alice
中科院分区：
文献类型：
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作者：
Lin,Cheng-Chieh;Wagenaar,RobertC;Young,Daniel;Saltzman,ElliotL;Ren,Xiaolin;Neargarder,Sandy;Cronin-Golomb,Alice
在帕金森病（PD）患者中发现了视觉障碍，并可能影响导航过程中视觉流对前进方向的感知。对健康受试者的研究证实，可以通过平衡视野之间的光流速度（OS）来确定方向。本研究研究了PD对导航过程中光流在前进方向、行走参数和肢体间协调方面的影响，考察了OS和空间频率（点密度）的贡献。12名无痴呆的PD患者、18名年龄匹配的正常对照成人（NC）和23名年轻对照成人（YC）以约0.8米/秒的速度走过虚拟走廊。走廊是由侧壁上的随机点构成的。在一面墙上设置3个OS（0.8、1.2和1.8 m/s）和点密度（1、2和3个点/m2），另一面墙上设置OS和点密度分别为0.8 m/s和3个点/m2。采集三维运动学数据，计算横向漂移、行走速度、步频和步幅，以及臂与腿之间的频率和相位关系。YC和NC在较低的OS下观察到显著的线性效应，但PD没有。与YC和NC相比，PD在OS和点密度条件下更偏向左侧。结果表明，健康成人对前进方向有视流感知。脑半球间多巴胺水平的不对称性和运动侧化（以手性为指标）可能更多地影响PD患者的头部方向。
Visuoperceptual disorders have been identified in individuals with Parkinson’s disease (PD) and may affect the perception of optic flow for heading direction during navigation. Studies in healthy subjects have confirmed that heading direction can be determined by equalizing the optic flow speed (OS) between visual fields. The present study investigated the effects of PD on the use of optic flow for heading direction, walking parameters, and interlimb coordination during navigation, examining the contributions of OS and spatial frequency (dot density). Twelve individuals with PD without dementia, 18 age-matched normal control adults (NC), and 23 young control adults (YC) walked through a virtual hallway at about 0.8 m/s. The hallway was created by random dots on side walls. Three levels of OS (0.8, 1.2, and 1.8 m/s) and dot density (1, 2, and 3 dots/m2) were presented on one wall while on the other wall, OS and dot density were fixed at 0.8 m/s and 3 dots/m2, respectively. Three-dimensional kinematic data were collected, and lateral drift, walking speed, stride frequency and length, and frequency, and phase relations between arms and legs were calculated. A significant linear effect was observed on lateral drift to the wall with lower OS for YC and NC, but not for PD. Compared to YC and NC, PD veered more to the left under OS and dot density conditions. The results suggest that healthy adults perceive optic flow for heading direction. Heading direction in PD may be more affected by the asymmetry of dopamine levels between the hemispheres and by motor lateralization as indexed by handedness.