title: Broad bandwidth of perceptual learning in second-order contrast modulation detection.
abstract: Comparing characteristics of learning in first- and second-order systems might inform us about different neural plasticity in the two systems. In the current study, we aim to determine the properties of perceptual learning in second-order contrast modulation detection in normal adults. We trained nine observers to detect second-order gratings at an envelope modulation spatial frequency of 8 cycles/° with their nondominant eyes. We found that, although training generated the largest improvements around the trained frequency, contrast sensitivity over a broad range of spatial frequencies also improved, with a 4.09-octave bandwidth of perceptual learning, exhibiting specificity to the trained spatial frequency as well as a relatively large degree of generalization. The improvements in the modulation sensitivity function (MSF) were not significantly different between the trained and untrained eyes. Furthermore, training did not significantly change subjects' ability in detecting first-order gratings. Our results suggest that perceptual learning in second-order detection might occur at the postchannel level in binocular neurons, possibly through reducing the internal noise of the visual system.
authors: Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China, Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, China.
authors: Jiawei
authors: J
authors: Zhou
authors: Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China, University of Chinese Academy of Sciences, Beijing, China.
authors: Fangfang
authors: F
authors: Yan
authors: Laboratory of Brain Processes, Department of Psychology, Ohio State University, Columbus, OH, USA.
authors: Zhong-Lin
authors: ZL
authors: Lu
authors: Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, China.
authors: Yifeng
authors: Y
authors: Zhou
authors: Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
authors: Jie
authors: J
authors: Xi
authors: Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
authors: Chang-Bing
authors: CB
authors: Huang
mesh_terms: D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: generalizability; modulation sensitivity; perceptual learning; second-order modulation detection; specificity