Visual Field Asymmetry in a Visual Search Task with Interfering Stimuli - A Reaction Time Study

Abstract

In visual search tasks, interfering stimuli capture attention and influence target finding. Information processing in the left and right visual fields differs, and visual search performance should be examined about the visual field and eccentricity. The study investigated the effects of disturbing stimuli presented at three eccentricities （10°, 20°, and 30°） under different perceptual loads on attentional capture from reaction times. An interaction between the visual field, perceptual load, and eccentricity was observed. Reaction times were longer in the right visual field than in the left visual field at 10° and 30° and shorter in the left visual field at 20° in the low perceptual load condition. In the high perceptual load condition, the left visual field was longer than the right visual field at 10° and 30°. Regarding eccentricity, in the low perceptual load condition, reaction times were longer in the right visual field at 10° and 30° than at 20°, and the opposite for the left visual field. In the high perceptual load condition, no significant differences in reaction time with eccentricity were observed in the right visual field, while in the left visual field, 20° was shorter than 10° or 30°. Attention capture was the result of the combined effects of several factors. It reveals hemispheric asymmetries in the brain regarding spatial attention.