Lexical And Gestalt Principle Object Influence The Object-based Attention

In daily life, we hope to response to the stimulus as soon as possible, which is a necessary ability promoted with human evolution. The ability depends on not only the distance between attention and stimulus, but also whether the initial attention and the stimulus are in the same object. The RT(reaction time) is shorter when the initial attention and the stimulus are in the same object than when they are not. This phenomenon is called object-based attention in psychology. The number of object types which can induce such a phenomenon is large. It contains the objects formed by gestalt principles and those formed by some top-down fashions as Chinese words. The diversity of object types makes more and more researches focusing on how different types of objects affect attention.The most popular paradigm on object-based attention is two-rectangle cueing paradigm. In this paradigm, though the target and cue appear in different space location, the distance between them is the same all the time. In some conditions, the target and cue appear in the same object, in the others, they appear in different objects. The result finds that the RT is shorter when they appear in the same object than when they are in different objects. The RT difference between the two conditions is called object-based effect. The rectangles used in this paradigm are formed by gestalt principle.The previous researches mainly focused on how the different object types affected object-based attention, whereas recent researches focus on the interaction between gestalt principle objects and some top-down fashions, dedicating to finding the key factors affecting their competition result. The present study uses the two-rectangle cueing paradigm. The two rectangles formed by gestalt principle and Chinese two characters words formed by top-down fashion are used as two different types of objects. Our study mainly focuses on how the attention deployment is affected when the two different types of objects meet congruous or incongruous and what is the mechanism the result bases on.This study contains a series of seven experiments for two parts.The first part contains five experiments, focusing on whether top-down fashion can override gestalt principle objects unconditionally when they conflict. The experimnet1verifies that the objects formed by Chinese words can induce object-based effect as gestalt principle objects even without memory test. Basing on the experiment1, the experimnet2arranges Chinese words objects and gestalt principle objects congruously, finding that the additive object-based effect is not larger than that induced by each of them. This result suggests that the object-based effect induced by different types of objects can't be additive. The experiment3arranges Chinese words objects and gestalt principle objects oppositely, finding that the object-based effect disappears and either object can dominate the attention deployment. Whereas, the value of object-based effect has no statistically significant difference with that induced by each type of object. The fact that no interactions are observed in experiment2and3may be due to the object-based effect being small in numeric value, which makes statistical result can not reflect the relationship between object-based effects observed under various conditions. Thus, the experiment4combines the congruous(in which the two types of objects are arranged in the same orientation) and incongruous(in which the two types of objects are arranged in opposite orientations) conditions. Because the difference between object-based effects induced by these two extreme conditions should be larger than the difference between object-based effects observed under incongruous and Chinese words only(in which only objects formed by Chinese words are showed) conditions, meanwhile, it also should be larger than the difference between object-based effects observed under incongruous and rectangles only(in which only rectangles are showed) conditions. Due to this reason, we anticipate that the statistical p value of interactions in experiment4should be more significant than that in experiment3. The result of experiment4conform it. Experiment5changes the "Block" presentation means used in experiment4to "Random" means, which can avoid subjects to use rectangle for grouping characters into Chinese words efficiently. This makes the object-based effect decrease in incongruous condition further. Thus, the statistical p value of interactions in experiment5should be more significant than that in experiment4. The result of experiment5reconform it. So, even the numeric value of object-based effect is small, the significant level in statistic can accurately reflect the relationship between object-based effects observed under various conditions.The part one of this study finds that the object-based effect disappears when the Chinese words objects and the gestalt principle objects are arranged oppositely. This may be due to the strength of the two types of objects is equal and either object can override the other one. IF the strength is indeed the key factor, changing the strength of one type of object can lead attention to be affected more by the stronger objects. Thus, the part two of this study contains two experiments and is to reveal what is the key factor affecting the results when the two types of objects compete. The experiment6changes the physical properties of gestalt principle objects to enhance the object strength. The result finds that the attention deployment is affected by gestalt principle objects. The experiment7grants familiarity mumeber to each Chinese word via subjective evaluating the familiarity of Chinese words. It finds that the Chinese words with high familiarity can dominate the attention deployment much easier than those with low familiarity under incongruous condition. Meanwhile, With the Chinese words familiarity decreasing, the attention deployment is affected not by both of objects but only by gestalt principle objects. The results of the experiment6and7reveal that the competition result induced by gestalt principle objects and top-down fashion objects is mainly determined by their strength contrast. The attention deployment is mainly affected by the object which has higher strength.According to the study results above, we make conclusion as below:1. The objects formed by top-down fashion (e.g. lexical information) are the same to the objects formed by gestalt principle in affecting the attention deployment. The subjects with Chinese language as their mother tongue can compound Chinese characters into words without too much psychological resource. The objects formed by Chinese words can induce object-based effect with no memory tests.2. The object-based effects induced by gestalt principle objects and Chinese words can't be additive. This result suggests that the enhancing levers of different types of objects which are constructed by different brain area enhancing may not be additive linearly.3. Whether object-based effect can be observed is determined by the strength contrast between top-down fashion and gestalt principle objects. When the strength of the two types of objects is equal, object-based effect will disappear, which is consistent with Biased Competition Account.4. For the gestalt principle objects, their physical properties determine the strength. Enhancing their physical properties can strengthen this type of object and can make it have advantage in the competition with Chinese words object. The strength of object formed by lexical information is determined by their familiarity. With the Chinese words familiarity decreasing, the strength of Chinese words object becomes weaker, which makes it at a disadvantage in the competition with gestalt principle objects.The fact that the attention deployment is inclined to be affected by gestalt principle objects further reveals that the strength contrast determines which one can dominate the attention deployment when top-down fashion conflicts with gestalt principle objects. The mechanism for the researches which found that top-down fashion could override gestalt principle objects when it was benefit for subjects to complete their tasks is that the strength of the top-down fashion is much higher than that of the gestalt principle objects.