# Numerical values modulate size perception

## TL;DR

This study shows that numerical values influence how we perceive the physical size of digits.

## Contribution

The research demonstrates that numerical magnitude affects physical size perception in a shared mental representation.

## Key findings

- Participants overestimated the physical size of numerically larger digits.
- Participants underestimated the physical size of numerically smaller digits.
- The findings support a shared-representation account of physical and numerical magnitudes.

## Abstract

The link between various codes of magnitude and their interactions has been studied extensively for many years. In the current study, we examined how the physical and numerical magnitudes of digits are mapped into a combined mental representation. In two psychophysical experiments, participants reported the physically larger digit among two digits. In the identical condition, participants compared digits of an identical value (e.g., “2” and “2”); in the different condition, participants compared digits of distinct numerical values (i.e., “2” and “5”). As anticipated, participants overestimated the physical size of a numerically larger digit and underestimated the physical size of a numerically smaller digit. Our results extend the shared-representation account of physical and numerical magnitudes.