Moving along the mental number line: Interactions between whole-body motion and numerical cognition.

Abstract

Active head turns to the left and right have recently been shown to influence numerical cognition by shifting attention along the mental number line. In the present study, we found that passive whole-body motion influences numerical cognition. In a random-number generation task (Experiment 1), leftward and downward displacement of participants facilitated small number generation, whereas rightward and upward displacement facilitated the generation of large numbers. Influences of leftward and rightward motion were also found for the processing of auditorily presented numbers in a magnitude-judgment task (Experiment 2). Additionally, we investigated the reverse effect of the number-space association (Experiment 3). Participants were displaced leftward or rightward and asked to detect motion direction as fast as possible while small or large numbers were auditorily presented. When motion detection was difficult, leftward motion was detected faster when hearing small number and rightward motion when hearing large number. We provide new evidence that bottom-up vestibular activation is sufficient to interact with the higher-order spatial representation underlying numerical cognition. The results show that action planning or motor activity is not necessary to influence spatial attention. Moreover, our results suggest that self-motion perception and numerical cognition can mutually influence each other.

Number generation bias after action observation

“…Since the time course of mental processes is not known, one cannot exclude that eyes movements in fact followed the mental selection of the number to be produced. This causal link is better shown in studies in which participants were found to produce more small-magnitude numbers after turning their head to the left than to the right (Loetscher et al 2008) or when passively experiencing whole-body motion to the left (Hartmann et al 2011). The present experiment differs from the latter studies as no actual movement was performed or experienced by the participants themselves, but it demonstrates a similar causal link, here between grip movement observation and number selection and production.…”

“…This was attributed to the well-known numberspace association, with small numbers being associated to the left part of space (Dehaene et al 1993). A recent experiment reported a similar finding with passive wholebody motion (Experiment 1 in Hartmann et al 2011). The participants were installed on a moving platform and generated numbers while the platform was moving in various directions.…”

“…The present findings reveal that the response selection stages of numbers can also be affected by action observation. Consequently, we suggest that the magnitude code of action could exert its effect not only on the stages where numbers must be comprehended and processed, as is the case in most previous studies in which a decision has to be taken by the participant on numbers that are delivered by the experimenter, but also on the stage where numbers are mentally self-selected by the participant (for a similar argument, see Hartmann et al 2011).…”

Which numbers do you have in mind? Number generation is influenced by reading direction

“…Leftward head turns led to smaller numbers being generated than rightward head turns (Loetscher et al 2008), leftward passive movement of participants facilitated smaller number generation (Hartmann et al 2012), and turning left when walking led to smaller numbers being generated (Shaki and Fischer 2014). These effects are further examples of the well-known association between space and number.…”

Exploring the numerical mind by eye-tracking: a special issue

“…These results confirm previous claims of a bi-directional link between physical and representational numerical space (cf. Fischer, Castel, Dodd, & Pratt, 2003;Hartmann, Grabherr, & Mast, 2012;Zorzi, Priftis, & Umilta, 2002).…”