The influence of self-experienced iconic finger-postures on numerical processing: Hemispheric asymmetries in semantic...

Embodied cognition theories suggest that abstract concepts, like numbers, are understood through the sensory-motor system. Iconic finger gestures have been shown to facilitate number processing, implying a shared semantic code between finger and Arabic numeral representations. This study used the Divided Visual Field paradigm to investigate where this cross-modal priming occurs in the brain. Twenty-four participants identified Arabic digits (2-3-4) by pressing a key with one hand, while their non-responding hand remained in a canonical (culturally-typical) or non-canonical finger posture. Results revealed faster reaction times in the left hemisphere when the hand was in a canonical posture but only when bodily and visual information matched within the same hemisphere. No semantic priming was observed in the right hemisphere, highlighting a hemispheric asymmetry in integrating finger-numeral and Arabic-digit representations. These findings demonstrate a clear left-hemispheric specialization in the semantic integration of finger and numeral representations, at least for small numbers.