Bronstein A M, Hood J D, Gresty M A, Panagi C
Medical Research Council Neuro-Otology Unit, Institute of Neurology, Queen Square, London, UK.
Brain. 1990 Jun;113 ( Pt 3):767-79. doi: 10.1093/brain/113.3.767.
The role of vision in the control of balance in patients with Parkinson's disease (PD) and cerebellar disease (CD) was studied by measuring body sway with eyes open, closed, and in response to visual stimuli generated by discrete lateral displacements of a moveable room which enclosed the subjects. In response to room movement, normal subjects swayed by an amount intermediate between sway with eyes open and eyes closed and their response attenuated on repetition of the movement, a process depending on shifting from predominantly visual to proprioceptive control. CD patients swayed more than controls with eyes open or closed and as shown by high 'Romberg quotients' (eyes closed/eyes open sway ratio) were able to use visual information to control much of their unsteadiness. CD patients had a normal attenuation of response to repetition of the room movement. PD patients had normal sway with eyes open or closed but their responses to room movement were abnormal, being proportionately larger and failing to attenuate during successive stimuli. The results indicate that cerebellar lesions seem largely to spare the visuopostural loop and also spare the ability to shift from a visual to a proprioceptive control of postural sway. In contrast, the findings in PD suggest that the visuopostural loop is hyperactive and that its influence cannot easily be de-emphasized when visual information is misleading. The latter finding suggests that basal ganglia participation in posture is concerned with the reweighting of the various sensorimotor loops controlling posture in the process of adapting to novel situations.
通过测量受试者在睁眼、闭眼以及对由围绕其的可移动房间的离散侧向位移产生的视觉刺激做出反应时的身体摇摆，研究了视觉在帕金森病（PD）和小脑疾病（CD）患者平衡控制中的作用。对于房间移动，正常受试者的摇摆幅度介于睁眼和闭眼时的摇摆幅度之间，并且他们的反应在移动重复时会减弱，这一过程取决于从主要的视觉控制向本体感觉控制的转变。CD患者在睁眼或闭眼时的摇摆都比对照组更大，并且如高“罗姆伯格商数”（闭眼/睁眼摇摆比率）所示，他们能够利用视觉信息来控制大部分的不稳定。CD患者对房间移动重复的反应有正常的减弱。PD患者睁眼或闭眼时的摇摆正常，但他们对房间移动的反应异常，反应相对更大且在连续刺激期间不会减弱。结果表明，小脑病变似乎在很大程度上保留了视觉姿势环路，也保留了从视觉控制向本体感觉控制姿势摇摆的转换能力。相比之下，PD的研究结果表明视觉姿势环路过度活跃，并且当视觉信息产生误导时，其影响不容易被弱化。后一项发现表明，基底神经节参与姿势调节与在适应新情况的过程中对控制姿势的各种感觉运动环路进行重新加权有关。
