Right visual field advantage for lexical decision dependent on stimulus size and visibility: Evidence for an early processing account of hemispheric asymmetry.

Abstract

Previous research suggests that the right visual field advantage on the lexical decision task occurs independent of the visual quality of stimuli [Chiarello, C., Senehi, J., & Soulier, M. (1986). Viewing conditions and hemisphere asymmetry for the lexical decision. Neuropsychologia, 24(4), 521-529]. However, previous studies examining these effects have had methodological limitations that were addressed and controlled for in the present study. Participants performed a divided visual field, lexical decision task for words that varied in size (Experiment 1) and visibility (Experiment 2). Results showed a quality by visual field interaction effect. In both experiments, response times were faster for targets presented to the right visual field in the high quality (i.e., large font, high visibility) conditions; however, visual quality resulted in no differences for targets presented to the left visual field. Furthermore, this quality by visual field interaction effect was only observed when the target was a word. These results suggest that the left hemisphere advantage for lexical decision depends on the perceptual quality of targets, consistent with an early stage of processing account of hemispheric asymmetry during lexical decision. Findings are discussed within the context of word recognition and decision-based models.