Andy Clark - University of Edinbergh

Hierarchical Predictive Processing (HPP)

“Top-down” - reversal of stimulus driven perception. Meta-Bayesian; predicts the sensory signal from stored information about the world.

“While trapped in a cabin with Dennett in Maine” - presenting the Paleontologist’s problem- students cheating by copying. Devised SLICE, a program that required student to recreate scene by applying “knobs” which caused various outcomes.

A prediction task bootstraps one into the information necessary to do further prediction (next word predicted by grammar; grammar provided through prediction and result evaluation)

Prediction Error “flows forward” - HPP.

Examples: Hollow Face Illusion - strong prediction of convex face trumps sensory input.

Perception vs. Action- action predicts proprioceptive states.

3 quants: Prediction, prediction error, and prediction weight.

Weight is a judgment of precision on PE- too little precision will ignore patterns, too high will hallucinate.

The point here is that the priors-the familiar, predicted information- really is the perception

Experiments - Continuous Flash Suppression

  • is language a prerequisite for deliberative imagination