Spatial attention can modulate unconscious orientation processing.
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.
Bahrami
Bahador
B
Institute of Cognitive Neuroscience, University College London, Alexandra House, 17 Queen Square, London WC1N 3AR, UK. bbahrami@ucl.ac.uk
Carmel
David
D
Walsh
Vincent
V
Rees
Geraint
G
Lavie
Nilli
N
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