Further evidence that the SNARC effect is processed along a dual-route architecture: Evidence from the lateralized readiness potential.
In a binary response setting, it has been frequently observed that small numbers are reacted to faster with the left hand and large numbers with the right hand (i. e., the SNARC-effect) which reflects the spatial left-right orientation of the mental number line (Dehaene, Bossini, & Giraux, 1993). In line with the work of Keus and Schwarz (in press), we investigated the locus of the conflict in the SNARC effect in a parity judgment task with the Arabic numerals 1, 2, 8, or 9. Differences between compatible (left-hand response to 1 or 2 and right-hand response to 8 and 9) and incompatible SNARC conditions (left-hand response to 8 or 9 and right-hand response to 1 or 2) were observed in the lateralized readiness potential (LRP) but not in the peak latency of the P300. In accordance with Keus and colleagues (Keus, Jenks, & Schwarz, 2005), we argue that the locus of the conflict is situated at intermediate response-related stages. However, instead of adopting a single-route processing architecture, a dual route account is proposed as the underlying processing architecture explaining the SNARC effect.
Gevers
Wim
W
Department of Experimental Psychology, Ghent University, Belgium. Wim.Gevers@Ugent.be
Ratinckx
Elie
E
De Baene
Wouter
W
Fias
Wim
W
D000328:Adult; D001143:Arousal; D004215:Distance Perception; D004569:Electroencephalography; D004585:Electrooculography; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D014796:Visual Perception