Davis Glasser
Physics & Astronomy
The Rapidly Generated Motion Aftereffect: Psychophysics and Physiology
Tuesday, July 19
12:00- 1:00 PM
Goergen 101
First documented by Aristotle, the motion aftereffect (MAE) is one of the best-known illusions in vision science. After adapting to a strong moving stimulus (like a waterfall, or the notes in Guitar Hero), subsequently viewed stationary objects seem to move in the opposite direction. In over 150 years of modern investigation, the MAE has typically been studied following tens of seconds of adaptation, which raises some important questions. Can perceptual adaptation be observed at brief, functionally relevant timescales? And if so, how do its properties relate to the rapid adaptation seen in cortical neurons?
In recently published work, we’ve shown that just 25 ms of motion adaptation is sufficient to generate the MAE, even when the motion is too brief to be discriminated. In parallel neurophysiological recordings, we find that brief motion adaptation evokes direction-selective responses to subsequently presented stationary stimuli. A simple model shows that these neural responses can explain the consequences of rapid perceptual adaptation. Overall, we show that the MAE is not merely an intriguing perceptual illusion, but rather a reflection of rapid neural and perceptual processes that can occur essentially every time we experience motion.
