title: Spatial attention can modulate unconscious orientation processing.
abstract: It has recently been suggested that visual spatial attention can only affect consciously perceived events. We measured the effects of sustained spatial attention on orientation-selective adaptation to gratings, rendered invisible by prolonged interocular suppression. Spatial attention augmented the orientation-selective adaptation to invisible adaptor orientation. The effect of attention was clearest for test stimuli at peri-threshold, intermediate contrast levels, suggesting that previous negative results were due to assessing orientation discrimination at maximum contrast. On the basis of these findings we propose a constrained hypothesis for the difference between neuronal mechanisms of spatial attention in the presence versus absence of awareness.
authors.affiliation: Institute of Cognitive Neuroscience, University College London, Alexandra House, 17 Queen Square, London WC1N 3AR, UK. bbahrami@ucl.ac.uk
authors.forename: Bahador
authors.initials: B
authors.lastname: Bahrami
authors.forename: David
authors.initials: D
authors.lastname: Carmel
authors.forename: Vincent
authors.initials: V
authors.lastname: Walsh
authors.forename: Geraint
authors.initials: G
authors.lastname: Rees
authors.forename: Nilli
authors.initials: N
authors.lastname: Lavie
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology*; D000328:Adult; D001288:Attention; D005133:Eye Movements; D005260:Female; D005366:Figural Aftereffect; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009949:Orientation; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011601:Psychophysics; D011930:Reaction Time; D013028:Space Perception / Q000502:physiology*; D055815:Young Adult