Invited talk: Peggy Series (Univ. Edinburgh)
The second project (Chalk, Seitz and Series, submitted) is an
experimental investigation of the influence of expectations on the
perception of simple stimuli.
Expectations broadly influence our experience of the world. However,
the process by which expectations are acquired and then shape our
sensory experiences is not well understood.
Using a simple task involving estimation and detection of motion
random dots displays, we examined whether expectations can be
developed implicitly through in a fast statistical learning procedure.
We found that participants quickly and automatically developed
expectations for the most frequently presented directions of motion,
and that this strongly altered their perception of new motion
directions, inducing attractive biases in perceived direction as well
as visual hallucinations in the absence of a stimulus.
We show that in this case, the perceptual biases are consistent with
optimal Bayesian Inference and discuss their possible biological
substrate.7