Daniel Goldreich, a professor at McMaster University, will present "A Bayesian Perceptual Explanation for the Tactile Rabbit and Other Curious Cutaneous Illusions."

Speaker's abstract:

Sensorineural activity provides imprecise, often ambiguous information about the external world. A growing body of work suggests that the brain perceives amid uncertainty through a process of Bayesian inference, interpreting vague sensory information in light of prior experience to generate optimal percepts. Following an introduction to the principles of Bayesian inference – drawing on cognitive, auditory and visual examples – Goldreich will present a Bayesian perceptual model that replicates several interesting tactile illusions. For example, in the cutaneous rabbit and related illusions, perception strikingly shrinks the intervening distance and expands the elapsed time between consecutive taps to the skin. Goldreich will show that the Bayesian perceptual model reproduces these observed illusory effects: perceptual length contraction and time dilation.