Visuospatial priming of the mental number line.
It has been argued that numbers are spatially organized along a "mental number line" that facilitates left-hand responses to small numbers, and right-hand responses to large numbers. We hypothesized that whenever the representations of visual and numerical space are concurrently activated, interactions can occur between them, before response selection. A spatial prime is processed faster than a numerical target, and consistent with our hypothesis, we found that such a spatial prime affects non-spatial, verbal responses more when the prime follows a numerical target (backward priming) then when it precedes it (forward priming). This finding emerged both in a number-comparison and a parity judgment task, and cannot be ascribed to a "Spatial-Numerical Association of Response Codes" (SNARC). Contrary to some earlier claims, we therefore conclude that visuospatial-numerical interactions do occur, even before response selection.
Stoianov
Ivilin
I
Dipartimento di Psicologia Generale, Università di Padova, Via Venezia 8, 35131, Padova, Italy. ivilin.stoianov@unipd.it
Kramer
Peter
P
Umiltà
Carlo
C
Zorzi
Marco
M
D000328:Adult; D003463:Cues; D005260:Female; D005403:Fixation, Ocular; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D013028:Space Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*