动态随机点立体图视差诱发电位的研究

目的从电生理学角度探讨立体视的机制,为客观检测立体视提供参数。方法由微机产生动态随机点立体图刺激,记录30名近距离立体视健康成年人4′-150′不同大小交叉和非交叉引起的视差诱发电位（disparity evoked potential,DEP）。结果（1）不同视差的DEP均为宽大负正波;（2）45′交叉视差DEP的N波潜伏时最长,150′的N波潜伏时最短;4′和30′非交叉视差DEP的N波潜伏时最长,124′的N波潜伏时最短;（3）交叉视差DEP的P波振幅高峰出现在23′、60′及150′,非交叉视差DEP出现在15′、45′及72′;（4）各视差DEP的N波潜伏时、P波振幅的非交叉视差变化曲线较交叉视差整体性左移;小视差的交差视差与非交差视差DEP的N波潜伏时演变规律不同。结论DEP的N波潜伏时、P波振幅能够为客观检测立体视提供参数;立体视宜分为精细交叉与精细非交叉、粗略交叉与粗略非交叉立体视。（中华眼科杂志,2006,42：878-882）

Study on crossed and uncrossed disparity evoked potential of dynamic random dot stereogram

OBJECTIVE: To analyze the disparity evoked potentials (DEP) of fine disparities, coarse disparities, crossed disparities and uncrossed disparities and provide parameters of impersonal examining stereopsis. METHODS: A software package for generating dynamic random dot stereogram (DRDS) was developed as a visual stimulus to elicit DEP in 30 normal subjects. The DEP of every subject was recorded in different crossed and uncrossed disparity stimuli (4', 8', 15', 23', 30', 45', 53', 60', 72', 87', 102', 124', 150' of arc). RESULTS: (1) the constant negative-positive complex wave was observed in different disparity stimuli. (2) The N wave's latency of -45' was the longest, the N wave's latency of -150' was the shortest among crossed disparities. The N wave's latency of 4', 23' was the longest, the N wave's latency of 124' was the shortest among uncrossed disparities. (3) The amplitude peak of P wave occurred at -23', -60', -150' among crossed disparities. The amplitude peak of P wave occurred at 15', 45', 72' among uncrossed disparities. (4) All characteristic crossed disparities were smaller than the uncrossed disparities. The change orderliness of small crossed disparities was different from that of small uncrossed disparities. CONCLUSIONS: The N wave's latency and the P wave's amplitude can be used as parameters to impersonally examine stereopsis. These results suggest that stereopsis can be divided into fine crossed stereopsis, fine uncrossed stereopsis, coarse crossed stereopsis, and coarse uncrossed stereopsis.