title: Pupillary light reflex to light inside the natural blind spot.
abstract: When a light stimulus covers the human natural blind spot (BS), perceptual filling-in corrects for the missing information inside the BS. Here, we examined whether a filled-in surface of light perceived inside the BS affects the size of the short-latency pupillary light reflex (PLR), a pupil response mediated by a subcortical pathway for unconscious vision. The PLR was not induced by a red surface that was physically absent but perceptually filled-in inside the BS in the presence of a red ring surrounding it. However, a white large disk covering the BS unexpectedly induced a larger PLR than a white ring surrounding the BS border did, even though these two stimuli must be equivalent for the visual system, and trial-by-trial percepts did not predict PLR size. These results suggest that some physiological mechanism, presumably the retinal cells containing the photopigment melanopsin, receives the light projected inside the BS and enhances PLR.
authors.affiliation: 1] Department of Life Sciences, The University of Tokyo, Tokyo 153-8902, Japan [2] Department of Physiology, The University of Tokyo School of Medicine, Tokyo 113-0033, Japan [3] Japan Society for the Promotion of Science, Tokyo 102-8472, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Miyamoto
authors.affiliation: 1] Department of Life Sciences, The University of Tokyo, Tokyo 153-8902, Japan [2] Department of Psychology, The University of Tokyo, Tokyo 113-0033, Japan.
authors.forename: Ikuya
authors.initials: I
authors.lastname: Murakami
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D006801:Humans; D008027:Light; D009898:Optic Disk / Q000502:physiology* / Q000528:radiation effects; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D011680:Pupil / Q000502:physiology* / Q000528:radiation effects; D012025:Reflex, Pupillary / Q000502:physiology* / Q000528:radiation effects; D012160:Retina / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D017299:Rod Opsins / Q000378:metabolism; D013997:Time Factors; D014785:Vision, Ocular / Q000502:physiology* / Q000528:radiation effects; D055815:Young Adult; D000099210:Melanopsin
chemical_list: D017299:Rod Opsins; D000099210:Melanopsin