The Influence Of Two Position Information On SNARC Effect And The Ordinal Position Effect

Dehaene(1993)observed when Participants have to classify target numbers as odd or even,the left hand would be virtually closer to small numbers and vice versa for the right hand.This link between numbers and space is the spatial numerical associations of response codes(SNARC)effect.However,the questions that SNARC effect result from the long-term memory construct of a mental number line or temporally created position–space associations are under debate.It has been proposed that numbers are represented in long-term memory(LTM)as a left-to-right mental line,small numbers are mentally situated on the left,and larger numbers on the right.van Dijck and Fias(2011)discovered participants responded faster with the left hand to numbers,which were presented early in the to-be-memorized sequence,whereas numbers presented toward the end of the sequence were responded to faster with the right hand(ordinal position effect).They also found the positional effect with nonnumerical words positively correlated with the numerical SNARC measure.So they suggested a new account proposing the SNARC effect to result from a temporary association of numbers and space to be formed in working memory.In this study,two experiments were conducted to design two conditions of consistency and inconsistency based on the position information of numbers on the mental number line and working memory and to investigate whether SNARC effect and the ordinal position effect will occur under the two conditions and the causes,so as to provide a new perspective for revealing the relationship between SNARC effect and the ordinal position effect.The aim of Experiment 1 is to examined whether SNARC effect and the ordinal position effect will occur under the two conditions that the position of the numbers on the mental number line is consistent and inconsistent with the digital position in working memory sequences.Number magnitude(greater than 5 and less than 5)x the position of the number in the sequence(front and back)x response hands(left and right)as within-subjects three factors design,and the ratio of consistent and inconsistent number sequences was set to 1: 3.34 college participants were required to memorize a number sequence of five numbers,and continued to keep the memorized sequence in mind while they performed a magnitude judgement task.They only had to classify the magnitude of the number to press a respective response key,when a number of the tobe-memorized sequence was presented(go trial).Otherwise,they should not press any key(no go trial).The results found the existence of the two effects in the consistent number sequences,but two effects do not exist in inconsistent number sequences.This may be due to the high proportion of inconsistent number sequences,which requires the subjects to invest more cognitive resources in conflict detection and processing,thus occupying a large amount of working memory resources,resulting in the disappearance of the two effects.On this basis,Experiment 2 investigated the influence of the ratio changes of the two conditions on SNARC effect and the ordinal position effect.The experiment design and assignment of the Experiment 2 are similar to Experiment 1,except that Experiment 2 specifies the three inconsistent conditions.And the ratio of consistent and inconsistent number sequences was adjusted to 1: 1,32 college participants participated in the Experiment 2.The results showed that there are not only SNARC effect and ordinal position effect,but also a significant interaction between them.Simple effect analysis shows that SNARC and ordinal position effects exist in consistent and inconsistent conditions.The results of this study,on the one hand,indicate that the ratio of consistent and inconsistent number sequences was 1: 1,SNARC effect and the ordinal position effect will affect each other and exist in parallel under two conditions.SNARC effect result from a temporary association of numbers and space to be formed inworking memory,which also indicates that the ordinal position effect is a strong factor.In addition,the direction of SNARC effect also affect the direction of the ordinal position effect,and the semantic comprehension between the number magnitude and space(for example,small and left,large and right)affect the ordinal position effect.On the other hand,the proportion of the two conditions of consistent and inconsistent number sequence have different influences on the two effects,which indicates that number-space association is flexible and susceptible to the current task.This study explores the relationship between SNARC effect and the ordinal position effect,which has some important practical significance.