Citation

Chabanat E, Jacquin-Courtois S, Havé L, Kihoulou C, Tilikete C, Mauguière F, Rheims S, Rossetti Y. Neuropsychologia 2019; 128: 204-208.

Affiliation

Inserm UMR-S 1028, CNRS UMR 5292, ImpAct, Centre de Recherche en Neurosciences de Lyon, France; Université de Lyon, Université Claude Bernard Lyon 1, France; Service de rééducation neurologique, Pavillon Bourret, Hôpital Henry-Gabrielle, Hospices Civils de Lyon, 20, route de Vourles, Saint-Genis-Laval, France; Plate-forme 'Mouvement et Handicap', Hôpital Henry-Gabrielle et Hôpital Neurologique Neurologique Pierre Wertheimer, Hospices Civils de Lyon, 20, route de Vourles, Saint-Genis-Laval, France.

Copyright

(Copyright © 2019, Elsevier Publishing)

DOI

10.1016/j.neuropsychologia.2018.08.006

PMID

30102905

Abstract

Blindsight has been primarily and extensively studied by Lawrence Weiskrantz. Residual visual abilities following a hemispheric lesion leading to homonymous hemianopia encompass a variety of visual-perceptual and visuo-motor functions. Attention blindsight produces the more salient subjective experiences, especially for motion (Riddoch phenomenon). Action blindsight illustrates visuo-motor abilities despite the patients' feeling that they produce random movements. Perception blindsight seems to be the weakest residual function observed in blindsight, e.g. for wavelength sensitivity. Discriminating motion produced by isoluminant colours does not give rise to blindsight for motion but the outcome of the reciprocal test is not known. Here we tested whether moving stimuli could give rise to colour discrimination in a patient with homonymous hemianopia. It was found that even though the patient exhibited nearly perfect performances for motion direction discrimination his colour discrimination for the same moving stimulus remained at chance level. It is concluded that easily discriminated moving stimuli do not give rise to colour discrimination and implications for the 3 levels of blindsight taxonomy are discussed.

Copyright © 2018. Published by Elsevier Ltd.

Language: en

Keywords

attention-blindsight; cortical blindness; coulour; dorsal stream; motion; perception-blindsight; vision