普氏摆现象形成机制的探讨

The Investigation of the Formation of Pulfrich Effect

目的:探讨普氏摆现象的形成机制。方法:选择6名视力或矫正视力正常的硕士研究生作为受试者,利用校准过的SD2320W三维液晶显示器,呈现双眼刺激物。实验一:左右眼刺激物做来回往复运动,其亮度存在差异,模拟通常情形下的普氏摆现象。实验二:左右眼刺激物做来回往复运动,在运动轨迹的左右两端时没有亮度差异,在中间运动阶段有亮度差异。实验三:左右眼刺激物做来回往复运动,在运动轨迹的左右两端时存在亮度差异,在中间运动阶段没有亮度差异。结果:实验一被试可见明显的普氏摆立体现象,很好的模拟了通常情况下加滤光片观察到的普氏摆立体现象。实验二被试未见立体运动现象,被试知觉到摆球沿着实际的运动轨迹做来回往复的直线运动。实验三的被试知觉结果和实验一相同,被试可见明显的普氏摆立体现象。结论:普氏摆立体现象形成的根本原因不是神经信号传导的时间延时。当刺激物运动到左右两端位置,运动状态发生变化时,刺激物的亮度差异对普氏摆的形成有决定作用,普氏摆立体现象可能是由暗刺激物一方的眼动跟踪系统滞后造成的。

Objective：To investigate the formation of Pulfrich effect.Methods：Six Master students with normal vision or corrected normal vision were selected as subjects.The stimuli were presented on the calibrated SD2320W 3D LCD display.Experiment 1：To simulate the Pulfrich effect,the stimuli presented to the eyes were oscillating back and forth and the brightness of the stimuli in two eyes were different.Experiment 2：The stimuli presented to the eyes were oscillating back and forth.At the left and right end of the trajectory there was no brightness difference in two eyes.In the middle stages of the movement there was different brightness in two eyes.Experiment 3：The stimuli presented to the eyes were oscillating back and forth.At the left and right end of the trajectory there was brightness difference in two eyes.In the middle stages of the movement there was different brightness in two eyes.Results：In experiment 1,subjects perceived clearly three-dimensional movement phenomenon.It was a good simulation of the usual Pulfrich effect which was observed with the filter.Experiment 2：Subjects did not perceive three-dimensional motion phenomenon,the stimulus was perceived to move back and forth along the actual linear trajectory.Experiment 3：The perception of subjects in experiment 3 was same to experiment 1.Subjects perceived clearly three-dimensional movement phenomenon.Conclusion：The fundamental cause of the Pulfrich effect was not the temporal delay in the neural signal transmission.The key point of the formation of Pulfrich effect was the brightness difference of stimuli at the left and right end of the trajectory,where the motion state changed.The Pulfrich effect might be caused by the eye-tracking system delay of the dark side eye.