University of California, San Diego
The Department of Psychology is Honored
to Present a Talk by
Stuart Anstis
University of California, San Diego
"I Thought I Saw it Move: Studies in Motion Perception"
Presented on February 26, 2004
Location: The Crick Conference Room
Mandler Hall, room 3545
- Abstract:
- Some (fairly) new illusions of movement show that stimulus
contrast can profoundly alter visual signals of motion. During a
fog, moving cars appear to move slowly because low contrast reduces
perceived speed. In my "footsteps" illusion, a grey square that
drifts across stationary black and white stripes appears to stop and
start as it crosses each stripe, because its contrast keeps changing.
A similar setup will show illusory distortions in perceived
direction.
Higher perceptual processes massage these neural motion signals into the perception of moving objects. For instance, when two rods slide over each other their intersection can appear to rotate counterclockwise even though it really rotates clockwise, because the motion of terminators propagates along straight lines and is blindly (and incorrectly) assigned to the motion of the central intersection.
I shall discuss how these illusions of movement affect movies, flashing neon signs, and driving safety.
- About the Speaker:
- Dr. Stuart Anstis was born in England and was a scholar at Winchester and at Corpus Christi College, Cambridge. He took his Ph.D. at Cambridge with Prof. Richard Gregory. He has taught at the University of Bristol, UK, and at York University, Toronto, Canada. Since 1991 he has taught at the University of California, San Diego (UCSD). He has been a visiting scientist at the Smith-Kettlewell Institute, San Francisco, the San Francisco Exploratorium, and at IPRI in Japan. He has published about 120 papers on visual perception, including the perception of real and apparent motion, Pulfrich's Pendulum, movement aftereffects, contingent aftereffects, coloured afterimages, normal and defective colour vision in babies, adaptation to gradual change in luminance, and the apparent size of holes felt with the tongue. Has also worked on hearing, including adaptation to frequency-shifted auditory feedback, hearing with the hands, adaptation to gradual change in loudness, and perfect pitch; and on motor aftereffects after jogging on a treadmill. With George Mather and Frans Verstraten he edited a book on the motion aftereffect. He has given over 250 invited presentations on his research throughout the USA, Europe and Japan, including an invited address in the President's Symposium at the annual meeting of the Society for Neurosciences a few years back and the 1998 Max Wertheimer Lecture in Frankfurt. His work has been featured in Discover magazine (June 1993) and in occasional television programs. He has won awards as an outstanding teacher at York University and at Earl Warren College, UCSD, where he was invited to give the commencement speech to 8000 people at the graduation ceremony in June 1999.
For More Information About This Speaker:
- http://psy.ucsd.edu/~sanstis/
Dr. Anstis' Website.
