视觉表象眼动的变化:知识还是技能的差异?

Eye-movement Changes in Visual Imagery: Different Knowledge or Skills?

通过2个实验探讨了视觉表象的知识学习表征差异和技能训练表征差异对眼动的影响。实验1以没有三级跳远运动专业技能知识且对该运动的认知水平也较低的大学生为被试,结果表明,在完成高信息通达水平的表象任务时,注视点需要较短的持续时间,但眼跳距离会增大,眼跳频率会变低;实验2对表象任务的知识学习表征水平和技能训练表征水平进行操纵,分别以对实验任务进行过知识学习和专业技能训练的人为被试,结果表明,随着被试知识习得水平和技能水平表征能力的提高,不同表象任务信息通达水平间的眼动差异将消失,但技能训练型的被试其平均眼跳时间要短于知识学习型被试,注视点平均持续时间和平均眼跳距离则没有差异。实验结果说明源于视觉表象内在表征的差异会引起眼动的变化,表征的技能水平越高,眼动就越流畅,佐证了眼动对视觉表象功能性促进的观点。

Visual imagery is an important visuo-spatial representation, which has the same mental storage characteristics with visual perception（Romke, Kosslyn,＆ Hamel, 1997）, sharing the same brain mechanisms with visual perception（Ganis, Thompson, ＆Kosslyn, 2004; Kosslyn, Thompson, ＆Alpert, 1997）. As is known to all, fi xation is the primary source of visual perception information, and eye movement is very important to visual perception. So, does eye movement also play an important role in the visual imagery processing？ There are two contrasting accounts for the phenomenon. The functional account hypothesizes that the encoding of each eye fi xation during perception process participates, as an index in the location of the space in the subsequent image generation. Recently, researchers found that subjects who fi xed their gaze centrally during perception did the same spontaneously during imagery. The subjects who are free to explore during perception, but maintaining central fi xation during imagery, showed decreased ability to recall the pattern. They concluded that the eye scan paths during visual imagery reenact those of perception of the same visual scene and eye movements during mental imagery are not epiphenomenal but assist the process of image generation（Brandt ＆ Stark, 1997; Laeng ＆ Teodorescu, 2002）. Actually, whether regular eye movements promote the representation processing relies on the level of eye movement regularity of change that regular change task information accessibility of visual imagery would cause. If task information accessibility level change inevitably leads to eye movement regularity changes, it can be inferred that eye movements play a functional role in visual imagery. Based on the experimental paradigm of imagery evoked by speech, the effect of information access of motor imagery eye-movement was investigated. Experiment 1 with no triple jump professional skills and knowledge of the sport is also low cognitive level students were tested, the results show that with the increase of the level of representation of task information accessible, eye gaze point average duration shorter the average saccade distance increases and the average saccade time becomes longer, which is the existing research results are consistent; knowledge learning and skills training to characterize the level of the experimental characterization of the appearance of two pairs of manipulation tasks were carried out in the experimental task knowledge and professional skills training to learn human subjects, results showed that subjects with the acquisition of knowledge and skills to improve the ability to characterize the level of fi xation task information accessible in different levels of representation between the average duration, average saccade distance and average saccade time difference will disappear, but knowledge and learning and skills characterize differences in average saccade time differences, skills-based subjects whose average saccade time should be shorter than the knowledge of learning subjects, reached critical levels signifi cantly, no difference in the average fi xation duration and average saccade distance.