title: Dissociable processes for orientation discrimination learning and contextual illusion magnitude.
abstract: Previous research suggests an inverse relationship between human orientation discrimination sensitivity and tilt illusion magnitude. To test whether these perceptual functions are inherently linked, we measured both orientation discrimination sensitivity and the magnitude of the tilt illusion before and after participants had been trained for three days on an orientation discrimination task. Discrimination sensitivity improved with training and this improvement remained one month after the initial learning. However, tilt illusion magnitude remained unchanged before and after orientation training, at either trained or untrained orientations. Our results suggest that orientation discrimination sensitivity and illusion magnitude are not inherently linked. They also provide further evidence that, at least for the training periods we employed, perceptual learning of orientation discrimination may involve high-level processes.
authors: Experimental Psychology, University College London, London, United Kingdom; UCL Institute of Cognitive Neuroscience, London, United Kingdom.
authors: Charlotte Elizabeth Holmes
authors: CE
authors: Wilks
authors: UCL Institute of Cognitive Neuroscience, London, United Kingdom; Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom.
authors: Geraint
authors: G
authors: Rees
authors: Experimental Psychology, University College London, London, United Kingdom; UCL Institute of Cognitive Neuroscience, London, United Kingdom.
authors: Dietrich Samuel
authors: DS
authors: Schwarzkopf
mesh_terms: D000328:Adult; D004193:Discrimination Learning / Q000502:physiology; D005260:Female; D006801:Humans; D007088:Illusions / Q000235:genetics / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D010775:Photic Stimulation; D011594:Psychometrics; D011601:Psychophysics; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000235:genetics / Q000502:physiology