Constructing the present & The science of art and illusion
构建现在；艺术与错觉的科学
报告人：Patrick Cavanagh
Department of Psychology, Glendon College
Department of Psychological and Brain Sciences, Dartmouth College
报告时间：2019年 4月11日 10:30-12:00
报告地点：北京师范大学京师学堂第三会议室（地下一层）
报告人简介：
Patrick Cavanagh graduated in Communications Engineering from McGill University in 1968. An interest in artificial intelligence led to a Ph.D. in cognitive psychology from Carnegie-Mellon in 1972. He taught at the Université de Montréal in Psychology until 1989, when he moved to Harvard as a Professor of Psychology. Along with Ken Nakayama, he founded the Vision Sciences Laboratory at Harvard in 1990. In 2007, he accepted a Chaire d’Excellence at the Université Paris Descartes where he continues as the head of the Centre and Attention and Vision of the Laboratoire Psychologie de la Perception. He is an Emeritus Professor at Harvard and a Research Professor at Dartmouth. He is a member of the Society of Experimental Psychologists and received a 2012 Honorary Doctorate from the Université de Montréal.
报告摘要：
Illusions are errors in perception but sometimes they are errors on purpose. In particular, moving objects often appear to be ahead of their actual location but this serves a function in guiding eye movement to where the moving object will be when the eye movement lands. This result indicates that an object’s visual location is constructed at a high level where an object’s motion is discounted to recover its current location. I will present versions of this motion induced position shift in fMRI and patient studies then I will present a new version, the double drift, where the illusory shift is so large it appears to have no possible functional value. fMRI results show that this illusion is not present in the early visual cortex suggesting that perception itself emerges at a higher level. In the second half of the talk, we look at the most compelling visual illusion: art, where impressions of depth and light arise from nothing more than pigments on a flat surface. But even more is hidden in paintings than just their ability to mimic 3D scenes –unnoticed errors in paintings can reveal much about the workings of the brain. Painters often stray from photorealistic styles, taking liberties with the rules of physics to achieve a more effective painting. Critically, many of these transgressions of physics such as impossible shadows go unnoticed by viewers – these undetected errors are the ones that tell us which rules of physics actually count for visual perception. As artists find the rules they can break without penalty, they act as research neuroscientists and we have only to look at their paintings to uncover and appreciate their discoveries. I will end by showing how to use art and illusions to do “science by looking”, unlocking the basic rules of visual cognition discovered by artists.
