An ERP study for exploring illusory motion

Abstract

The aim of this study was to explore whether illusory motion stimulates the same pathways in the brain as real motion. Electroencephalogram (EEG) recordings were used to obtain Visual Evoked Potentials (VEPs) from the occipital region in the visual cortex. Two types of stimuli were used: 1) illusory motion displays, based on the work of Akiyoshi Kitaoka (Thornton & Zdravkovic, 2018), 2) random dot patterns, based on the stimuli used in a previous VEP study (Mercier et al. 2009). The VEPs for both types of stimuli were averaged across participants. Previous studies have identified three main components in VEPs to motion, labelled P1, N2 and P2, with the N2 peak expected to show the most divergence between real motion and static stimuli. We further tested whether motion or static differences in VEP components were modulated by attention. Results showed that for random dot stimuli, the three main components, P1, N2 and P2 were clearly visible, and were modulated by motion. However, for illusory motion, none of the components seemed to be present. There also appears to be no strong attention manipulation on either random dot or illusion stimuli.