Verification Of The Relation Between Perception And Action In Grasp Action

The dissociation between perception and action refers to the phenomena that visual perception and visual control of action correspond to the two different systems, which means the vision that controls perception is independent of the vision that controls action.In this research, using two-dimensional Titchener illusion pictures as experimental material, we studied the universality of the dissociation of perception and action and compared the rationality of two visual stream model and planning-control model. Two experiments were included. The first experiment examined the phenomena of the dissociation between perception and action in one-hand grasping and two-hand grasping situations. The effects of some important factors such as attention directing on the dissociation were explored. There were perception tasks and action tasks included i n t he first s tudy. The former m easured the size o f t he p erceptual i llusion, while the latter verified if the dissociation exists and examined its related factors. During action tasks, the subjects' action indexes, maximum grip apertures between their thumbs and index fingers, were recorded. The second experiment compared the rationality of two visual stream model and planning-control model of act. Perception tasks and action tasks were also performed by subjects in the second study. The former measured the size of the dynamic perceptual illusion, while the latter examined the influence of the change of the picture in grasping act upon the grasp action indexes, and hereby compared the two models.Several conclusions were drawn by us: 1 .It was found that the dissociation between t he action o f 1 eft/right h and a nd p erception appeared, t hough they all were influenced by illusion to some extent in one-hand situation. 2.The right hand was less influenced by illusion and the dissociation appeared clearly, while the results of the left hand were confused in two-hand situation. It was concluded that the dissociation exists, but it might be influenced by attention directing, attention-sharing strategies and the cooperative characteristics of two hands.3.Grasp action was not influenced by the perceptional change when the target pictures were the same in fact, but it was when the pictures were the same in perception.This research put forward our own opinion about the two models of relation between perception and action on the base of supporting two visual streams model.