An Exploration On The Mechanism Of The Same-different Judgment Based On Dimension Processing

Previous researches on attention has found the dimension switch effect, it means that one’s response would be more faster when defined dimensions in the previous trail are the same as the current defined dimensions, such as shape and color, etc. This discovery affords a reliable way of further researches on the same different judgement. Based on these, we carried out two experiments in order to announce not only the processing mechanism of the same different judgement but also the interaction between mutiple related dimensions. On the one hand, we took an explory on the judgements with two dimensions changed, on the other hand we would investigate the judgements with only one dimension changed.Previous studies has found a "fast-same effect". Some researchers explained it with the single-process model while others adopted the dual-process model. This divergence needs more researches to answer it. Moreover, if the single-process model was proved, another question arose, as several dimensions were included in the comparing process, whether their processing model was serial or parallel, had to be answered. All above indicated that further research must to be done to announce the mechanism of the same-different judgment.The first experiment of the literature manipulated the dimensions (color and shape) of the compared stimuli, each of which had five features. According to the congruency of the dimensions those stimuli belonged to, we classified them into four types, as follows:(1) same color and same shape,(conjunctive-match);(2) same color and different shape,(shape-mismatch);(3) different color and same shape,(color-mismatch);(4) different color and different shape,(conjunctive-mismatch). We were about to investigate subjects’ responses to the compared stimuli under the repeat and change of the mismatch dimensions in order to indicate the internal mechanism of the same-different judgment. The results showed that:(1) the "same" reactions to the conjunctive-match stimuli showed differences, when after various "different" reactions to those whose single dimension or double dimensions were different, which was against the dual-process model.(2) the "different" reactions to the conjunctive-mismatch stimuli were significantly faster than those to the stimuli whose single dimension was mismatched, which was against the serial process model; At the same time,(3) the "different" reactions under the condition of conversion from color-mismatch to the conjunctive-mismatch and under the condition of conversion from shape-mismatch made no significant difference, which held out the parallel process mechanism of the related multi-dimension. All results above were sustainable with that, a mechanism of the same-different judgment was that, multi-dimension were processed parallel in a single process, when the stimuli were presented simultaneously.The first experimental results have confirmed that the same-different judgement enforced the single-process model, the multiple related stimulus dimensions were processed in the parallel pattern. At the same time, the previous researches on the single-process mechanism, there were the following three ideas about the single-process mechanism:(1) Encoding Facilitation,(2) Response Priming,(3) Recheck. Those above suggest that how multiple related dimensions were processed in a single-process and how they deal with the interaction among them, also need further researches.The second experiment of the literature manipulated the shape features of the fixed color stimuli, that was to say the color dimension was fixed, the shape dimension was changed. We fixed a dimension constant while changing another dimension, at the same time, we could explore interactions between multiple stimulus dimensions processing, According to the congruency of the shape features, we classified them into four types, as follows:(1) same shape;(2) two shapes;(3) three shapes;(4) four shapes. By analysing the responses to the four types stimuli, the results revealed that the different judgements were slower than the same judgements, supported the related dimensions can be processed together, which agreed with the Response Priming model of the same-different judgement. Moreover, the different judgements took on great differences, the reaction speed of the four shapes stimuli was much faster than that of the three or two shapes stimuli, which indexed a good prominence of the dimension feature can facilitate one’s responses. Another, the responses after the two shapes stimuli were slower than those after the four shapes stimuli, which indexed a bad prominence of the dimension feature will slow one’s responses and can cause conflicts control to affect the later responses.Combined with the first experiment, the dimensions processing of the same-different judgements with simultaneous stimuli, carried out parallel in the single-process, a good prominence of the dimension feature can facilitate one’s responses.