Perceived state of self during motion can differentially modulate numerical magnitude allocation

Area of Science:

• Cognitive Neuroscience
• Perception
• Psychophysics

Background:

• Spatial attention and numerical cognition are fundamental cognitive processes.
• Previous research suggests a potential coupling between spatial attention and numerical allocation, but this link is debated.
• Visual and vestibular motion can influence spatial attention and numerical processing, but the underlying mechanisms are unclear due to confounding factors like eye movements and self-perception.

Purpose of the Study:

• To investigate how different perceptual experiences of motion modulate numerical magnitude allocation.
• To disentangle the effects of visual versus vestibular motion on numerical processing.
• To control for eye movements and task-specific effects to isolate the impact of self-perception during motion.

Main Methods:

• Optokinetic stimulation (OKS) was used to create distinct perceptual experiences of 'visual world' motion and 'self'-motion, with identical eye movements.
• A vestibular protocol involving perceived and subliminal angular rotations in darkness was employed, also ensuring identical eye movements.
• Participants' numerical magnitude allocation judgments were recorded under these controlled motion conditions.

Main Results:

• 'Visual world' motion induced by OKS biased numerical judgments: rightward motion favored smaller numbers, while leftward motion favored larger numbers.
• 'Self'-motion perception during OKS biased numerical judgments towards larger numbers, irrespective of OKS direction.
• Vestibular motion, whether perceived or subliminal, did not modulate numerical magnitude allocation.

Conclusions:

• Numerical magnitude allocation is differentially modulated by the perceptual state of 'self' during visually mediated motion.
• The influence of motion on numerical cognition depends on the sensory modality (visual vs. vestibular) and the subjective experience of self-motion.
• This study provides novel evidence for a link between bodily self-consciousness during visual motion and numerical cognition.