Spatial Reference System Of SNARC Effect

Dehaene and colleagues discovered an association of smaller numbers with the left responses, and larger numbers with the right responses, which was called the SNARC effect. They have tried to use "mental number line" to explain the digital space representation. Then, not only for the digital concept, similar SNARC effect have also been found in other sequences of numbers. However, with the development of SANRC effect research, there are other phenomena emerge which mental number line could not be explained.Based on the spatial cognition model proposed by McNamara and colleagues, this article propose that SNARC effect also involve two reference frame, which are egocentric reference frame and allocentric reference frame. In view of number-space representation, egocentric reference frame mean response direction being horizontal or vertical, and allocentric reference frame mean sequence instinct direction being horizontal or vertical. Three experiments were conducted in this article to explore the function of those two reference frame involved in SNARC effect.Experiment 1:there are four equal experiments to explore in which reference frame aligned condition SNARC effect would appear. The results showed us under the horizontal response condition, no matter what if egocentric reference frame and allocentric reference frame aligned or not, the standard SNARC effect would appear. However, no significant effect was found in vertical response condition.Experiment 2:there are three equal experiments to explore the coding way of alignment under horizontal response condition through operating the subject midpoint with instruction. The results showed significant SNARC effect under setting 3,5 and 7 as the midpoint in sequence 1-9, which mean the SANRC effect is coded by midpoint of sequence.Experiment 3:there are two equal experiments to explore in which way nonalignment of egocentric reference frame and allocentric reference frame triggered SNARC effect under the horizontal response condition by cluing two reference frame. The results showed that SNARC effect appeared in both two cluing condition. However, to clue egocentric reference frame is more economic than allocentric reference frame. Under nonalignment condition, egocentric reference frame is more applauded for SNARC effect.To summary all those three experiment results, conclusions of this article are as following:(1)Under the alignment of egocentric reference frame and allocentric reference frame condition, numbers are represented spatially followed the subject midline encoding.(2) Under the nonalignment of egocentric reference frame and allocentric reference frame condition, egocentric reference frame is more applauded for numeric spatial representation.Above all, people are not merely to build a mental line for the number serial when they conduct number-spatial representation, the relationship between number serial orientation and response orientation is necessary to be concerned. Thus, the nature of SNARC could be learned from a new sight, besides, it could be a base for large-scale space study.