Spatial reference frames and SNARC

In this work, the role that spatial reference frames play in determining the spatial-numerical association of response codes (SNARC) effect is examined. Participants were instructed to generate an image of the numbers 1–9 oriented spatially in either a horizontal, vertical, or proximo-distal manner. Responses to a magnitude comparison task were then provided manually using keys located either to the left and right or at the bottom and top of a computer keyboard. For conditions in which the orientation of the generated image and the response locations were orthogonally misaligned, SNARC effects were not evident. It is argued that such results imply that alignment of the spatial reference frames associated with the responses and with the representation of numerical magnitude is a necessary condition for the elicitation of the SNARC effect.