title: Attention enhances contrast appearance via increased input baseline of neural responses.
abstract: Covert spatial attention increases the perceived contrast of stimuli at attended locations, presumably via enhancement of visual neural responses. However, the relation between perceived contrast and the underlying neural responses has not been characterized. In this study, we systematically varied stimulus contrast, using a two-alternative, forced-choice comparison task to probe the effect of attention on appearance across the contrast range. We modeled performance in the task as a function of underlying neural contrast-response functions. Fitting this model to the observed data revealed that an increased input baseline in the neural responses accounted for the enhancement of apparent contrast with spatial attention.
authors.affiliation: Department of Psychology, New York University, New York, NY, USA.
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Cutrone
authors.affiliation: Department of Psychology, New York University, New York, NY, USA Center for Neural Science, New York University, New York, NY, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Heeger
authors.affiliation: Department of Psychology, New York University, New York, NY, USA Center for Neural Science, New York University, New York, NY, USA.
authors.forename: Marisa
authors.initials: M
authors.lastname: Carrasco
mesh_terms: D001288:Attention / Q000502:physiology*; D002755:Choice Behavior; D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D009431:Neural Conduction / Q000502:physiology*; D009949:Orientation; D011601:Psychophysics; D014793:Visual Cortex / Q000502:physiology*
keywords: contrast appearance; covert attention