New Evidence Of Brain Mechanisms In Depth Perceptual Of Ambiguous Figures Processing

Depth perception refers to the distance between the observer and the object,or it can refer to the distance between two objects or different parts of the same object.In a complex natural environment,it plays a key role in the cognitive process that humans can successfully perform object perception.Previous studies about depth perception emphasized that "If cues are clear,people are able to give a clear impression of the object and make an accurate judgment of the depth perception of the object." But few people care about the condition that the clues are unclear or missing,how people get depth perception.But,studies have proved that the clues are unclear or missing,humans can still judge the depth of the object with little research related.Therefore,in the absence of visual cues,the three-dimensional objects are perceived the concave or convex process of the neural mechanism and time characteristics to be further studied.Ambiguous figure refers to the subjects in the different period of time to produce two or more than two kinds of perceptual representation of the same object.Researchers have done a lot of studies about the cognitive mechanisms of the ambiguous figure,but the brain mechanism and the time course of the subjects' depth perception are unclear.Through the pervious ambiguous figure of the depth perception process,there are empirical results show that top-down processing,top-down processing and the two interactive processing methods.Based on previous studies,this study designed a behavioral experiment and an ERP experiment.Using the improved and evaluated ambiguous figure as stimulus materials,the subjects were asked to judge the relative depth perception of the two different color dots on the object.The results of the first experiment show that the subjects perceive different depth information are more likely to the state of the transition than the steady state,and the reaction time is longer.It reflects the influence of the complexity of the perception object on the cognitive processing.Compared with the concave perception,the subjects are more likely to be perceived convex when they are watching the ambiguous figures.The behavior results of the second experiment show that subjects were more likely to be perceived as ambiguous figure convex object,whereas the reaction time is longer.The ERP results of the second experiment revealed the following:(1)The larger N1 amplitude was evoked by the concave perception than the convex perception,which reflects the sufficient attention of the individual in the characterization of the depth information.(2)During the P3 time window,convex perception elicited a larger amplitude than the concave perception,which reflects the decision difficulty when using the weaker information to judge the depth of the object.Furthermore,significant differences between concave perception and a group of electrode sites in the right lateral occipital region,which reflects the processing of the right hemisphere "where" pathway to the depth information.These results show that,in the absence of clear depth of the clue,the perception system produces two different objects,the perception process and nerve response are also significantly different.To sum up,we believe that depth perception of ambiguous figure is begins from bottom to up and then from top to bottom two-way cognitive process.