Numbers and space: A computational model of the SNARC effect.

Abstract

The SNARC (spatial numerical associations of response codes) effect reflects the tendency to respond faster with the left hand to relatively small numbers and with the right hand to relatively large numbers (S. Dehaene, S. Bossini, & P. Giraux, 1993). Using computational modeling, the present article aims to provide a framework for conceptualizing the SNARC effect. In line with models of spatial stimulus-response congruency, the authors modeled the SNARC effect as the result of parallel activation of preexisting links between magnitude and spatial representation and short-term links created on the basis of task instructions. This basic dual-route model simulated all characteristics associated with the SNARC effect. In addition, 2 experiments tested and confirmed new predictions derived from the model.

Reversing the Manual Digit Bias in Two-Digit Number Comparison

“…This work provides empirical data in support of recent computational models of number representation Gevers, Verguts, Reynvoet, Caessens, & Fias, 2006) and showing that a purely embodied perspective is likely insufficient to account for the observed associations between symbolic number and space (Santens & Gevers, 2008;Gevers et al, 2010). Further, the present study adds to a growing body of work on the dynamics of cognitive processing, representing diverse topics such as stereotype formation (Freeman & Ambady, 2009), voice processing (Sulpizio et al, 2015), language comprehension (Spivey et al, 2005;Incera & McLellan, 2015), memory (Abney, McBride, Conte, & Vinson, 2014;Papesh & Goldinger, 2012), and face processing (Freeman & Ambady, 2011;Hehman, Carpinella, Johnson, Leitner, & Freeman, 2014).…”

The development of the SNARC effect: Evidence for early verbal coding

“…In their computational model of the SNARC effect, Gevers et al (2006) assume that the SNARC effect results from learned connections between magnitude labels (small/large), on the one hand, and spatial representational labels (left/right) on the other hand. Apparently, these connections are learned relatively early in development, and are resistant to extensive exposure to external spatial representations of number such as number lines, rulers, calendars, etc.…”

“…According to the spatial account, the SNARC effect results from a tight correspondence between the position of a number on a continuous left-to-right oriented representational medium (the "mental number line") and the spatial position of the response (Restle, 1970). Recently however, this strict spatial account of the SNARC effect has been questioned (Gevers, Verguts, Reynvoet, Caessens, & Fias, 2006;Fias, Van Dijck, & Gevers, 2011;Proctor & Cho, 2006) and a verbal account was proposed. According to this account, the SNARC effect results from an association between verbal codes such as "small" and "left," on the one hand, and between "large" and "right," on the other.…”

Is the SNARC Effect Related to the Level of Mathematics? No Systematic Relationship Observed despite More Power, More Repetitions, and More Direct Assessment of Arithmetic Skill

“…Moreover, the level of arithmetic skill was directly assessed by behavioural performance and not only by field of study. Finally, we assessed the general processing speed of participants in an independent task (simple RT) because it is known that slower RTs lead to larger SNARC effects (Gevers et al, 2006). In this way, we could test whether eventual group differences in the SNARC effect are rather due to differences in processing speed between participant groups than to arithmetic skill differences.…”

“…One such source of SNARC effect variability was pointed out by Gevers, Verguts, Reynvoet, Caessens, and Fias (2006). Participants who perform parity judgement faster display a smaller SNARC effect than those who react slower.…”