The Influence Of Explicit Or Implicit Numerical Processing On Spatial Numerical Associations

Spatial-Numerical Associations(SNAs)have always been the focus of mathematical cognition.This is mainly reflected in the fact that people use their left hand to react quickly to small numbers and their right hand to large numbers.This phenomenon is called Spatial Numerical Association of Response Code effect(SNARC effect).The classic "mental number line" theory proposes that the SNARC effect originates from a number line in the human mind,where numbers are automatically mapped from small to large to the space from left to right.But in recent years,mental number line cannot make a reasonable explanation for many results,so it is increasingly questioned.Spatial-numerical associations have different characteristics in different task settings.This flexibility is a strategic response to situations in working memory where tasks are temporarily performed.This research from the experimental setup of previous SNARC effect research defects(ignore the explicit or implicit numerical and spatial processing in the task affect the SNARC effect).This paper is to investigate how in the task without explicit spatial information processing,explicit or implicit numerical magnitude processing influences on spatial numerical associations,and to proofread the existing mental number line theory.In Experiment 1,Go/NoGo paradigm was used to explore the mechanism of spatial numerical associations.Subjects pressed the numbers and arrows in number classification and number parity task.In the two tasks,the number stimulus independent variables: number magnitude(small,large)and congruity(congruent,incongruent);and arrow independent variables: arrow direction(left,right),congruity(congruent,incongruent)and block rule(odd rule,even rule).The number results show that: in magnitude task of explicit numerical processing,the large number has the congruity effect,that is,the explicit numerical processing of the large number induces activation of the same spatial position on mental number line;in the parity task of implicit numerical magnitude processing,the congruity effect and interaction are not significant,and there is no spatial numerical associations.The results show that the main effect and interaction of arrow direction are significant in magnitude tasks,showing that the right arrow is faster than the left arrow;in the parity task,the main effect of arrow direction is significant,and the right arrow is faster than the left arrow.The arrow results suggest task set leads to activation of explicit spatial information processing,so it is an automatic activation point of view that spatial coding of numerical representation cannot be verified.In Experiment 2,using cue-target paradigm,subjects completed three tasks: number magnitude classification,number parity judgment and arrow color discrimination.The cue of number task is arrows,while arrow task is numbers.The results show that: the magnitude task of explicit numerical processing does not find spatial numerical association as Experiment 1;the parity judgment task of implicit numerical processing does not appear spatial numerical association,which is consistent with Experiment 1;spatial numerical association does not appear in the implicit spatial information processing of color task.These reveal that when the spatial information coding is implicit processing,strictly separated implicit and explicit numerical processing will not cause the automatic activation of spatial representation of numbers.In conclusion,this study suggests that under the premise of no activation of explicit spatial information,no matter whether the numerical processing is explicit or implicit,it will not automatically induce the spatial characteristics of numbers.These results support the view that spatial numerical associations originate from the temporary task execution in working memory,and challenge the theory of mental number line.