OKN眼动跟踪在运动文字识别中的作用

OKN EYE MOVEMENTS IN RECOGNITION OF MOVING TEXT

用运动文字的阅读眼动实验来研究运动图像识别与眼动控制的关系,并与一般OKN眼动及一般正常阅读进行对比,探讨了速度及位置信息处理与内容信息处理的关系.实验结果表明;(1)一般正常文字阅读的眼动是Saccades眼动与注视停顿;运动文字识别阅读的眼动中没有注视停顿,而是快、慢交替的OKN眼动,在其慢相期间即运动文字与视网膜相对静止期间采集内容信息进行处理,慢相期间既处理文字内容信息又处理运动速度信息,说明对运动速度与内容信息的处理是并行的.(2)在运动文字运动速度高达80°/s以上时,已不能阅读甚至不能识别单字意义,但仍可产生OKN眼动;这一方面证实阅读速度的受限不在于眼球运动的跟踪能力,而在于高级识别中枢的解码速度,另一方面也说明OKN眼动不是在识别后才产生,而是进行运动图象识别的必要条件.(3)运动文字识别阅读的速度不低于一般正常文字阅读的速度.本文的结果还证实OKN眼动的快相眼动有别于Foveating Saccades.

Eye-movement experiment for recognizing and reading moving Chinese text are performed. The experimental results show: (1) The eye-movement pattern during recognition of moving text is Optokinetic nystagmus ( OKN) . There are no fixation pauses and the content information is acquired during the velocity tracking. These results indicate that content information and velocity information are processed in parallel. (2) The maximum velocity of the moving text for eliciting OKN is much faster than that for recognition of moving text. Therefore , the OKN is not the effect of recognition, it is a precondition for recognition of moving pattern. (3) The reading rate measured for moving text is not less than that for normal reading. Our results also indicate that the fast phase of OKN is different from foveating saccades.