How does number magnitude influence temporal and spatial parameters of eye movements?

How does number magnitude influence temporal and spatial parameters of eye movements?
Exp Brain Res. 2019 Dec 03;:
Authors: Pressigout A, Dore-Mazars K
Abstract
The influence of numerical processing on individuals' behavior is now well documented. The spatial representation of numbers on a left-to-right mental line (i.e., SNARC effect) has been shown to have sensorimotor consequences, the majority of studies being mainly concerned with its impact on the response times. Its impact on the motor programming stage remains less documented, although swiping movement amplitudes have recently been shown to be modulated by number magnitude. Regarding saccadic eye movements, the few available studies have not provided clear-cut conclusions. They showed that spatial-numerical associations modulated ocular drifts, but not the amplitude of memory-guided saccades. Because these studies held saccadic coordinates constant, which might have masked potential numerical effects, we examined whether spontaneous saccadic eye movements (with no saccadic target) could reflect numerical effects. Participants were asked to look either to the left or to the right side of an empty screen to estimate the magnitude (< or > 5) of a centrally presented digit. Latency data confirmed the presence of the classical SNARC and distance effects. More critically, saccade amplitude reflected a numerical effect: participants' saccades were longer for digits far f...

Source: Experimental Brain Research - December 2, 2019 Category: Neuroscience Authors: Pressigout A, Dore-Mazars K Tags: Exp Brain Res Source Type: research