Are spatial-numerical associations of response codes reciprocal or not?
Mon-B21-Talk III-03
Presented by: Melanie Richter
The “spatial-numerical association of response codes“ (SNARC) effect denotes superior performance of left responses to smaller numbers and right responses to larger numbers, as compared to the opposite mapping. This finding provides evidence for associations, or even overlap, between the mental representations of number and space. While some existing accounts predict unidirectional associations between numerical and spatial stimulus and response codes, other accounts predict bidirectional associations between number and space. To investigate the reciprocity of the SNARC effect, we compared the compatibility effect in two manual choice-response tasks. In the number-location task, participants responded to one or two dots with a left or right key press. In the location-number task, participants responded to a left- or right-side stimulus with one or two keypresses. Each task contained one compatible (one-left, two-right; left-one, right-two) and one incompatible (one-right, two-left; left-two, right-one) mapping condition. A strong compatibility effect occurred in the number-location task, reflecting the typical SNARC effect. However, no compatibility effect occurred in the location-number task. The results thus indicate that numerical stimuli can facilitate the selection and execution of spatial responses, whereas spatial stimuli cannot facilitate the selection and execution of numerical responses. The finding that spatial-numerical associations are unidirectional appears consistent with some accounts of the SNARC effect such as the mental-number line hypothesis, but inconsistent with other accounts such as the polarity-correspondence principle.
Keywords: spatial-numerical associations; SNARC; reciprocity; symmetry; mental-number line; polarity correspondence;