Hou Chuan, Pettet Mark W, Norcia Anthony M
Smith-Kettlewell Eye Research Institute, San Francisco, CA 94115, USA.
J Vis. 2008 Apr 8;8(4):2.1-12. doi: 10.1167/8.4.2.
Coherent motion responses of patients with mild to moderate strabismic amblyopia were compared to those of normals using visual-evoked potentials (VEPs). Responses were elicited by dynamic random-dot kinematograms that alternated at 0.83 Hz between globally coherent (left-right) and incoherent (random) motion states. Tuning curves were measured at the first harmonic of the global motion update rate (0.83 Hz) and at the first harmonic of the dot update rate (20 Hz) for spatial displacements 3.1 to 27.9 arcmin (1.6 to 9.3 deg/s). Responses locked to the changes in the global organization of the local direction vectors were an inverted U-shaped function of displacement/speed in the normal-vision observers and in the fellow eyes of the strabismus patients while the tuning function of the amblyopic eyes was shifted to larger displacements/higher speeds. Responses at the dot update rate were reduced in amplitude and altered in timing in both eyes of the patients. The results are consistent with both local and global deficits in motion processing in strabismic amblyopia.
利用视觉诱发电位（VEP）比较了轻度至中度斜视性弱视患者与正常人的连贯运动反应。通过动态随机点运动图诱发反应，该运动图在全局连贯（左右）和不连贯（随机）运动状态之间以0.83Hz交替。在全局运动更新率（0.83Hz）的一次谐波和点更新率（20Hz）的一次谐波处测量调谐曲线，空间位移范围为3.1至27.9分视角（1.6至9.3度/秒）。在正常视力观察者和斜视患者的健眼中，锁定于局部方向向量全局组织变化的反应是位移/速度的倒U形函数，而弱视眼的调谐函数则向更大位移/更高速度偏移。患者双眼在点更新率处的反应幅度降低且时间改变。结果与斜视性弱视运动处理中的局部和全局缺陷均相符。
