Kanizsa triangle Gregory’s Indirect Theory (1974) Top-down theory of perception.

Kanizsa triangle

Gregorys Indirect Theory (1974)Top-down theory of perception

Gregorys indirect theoryPerception process of construction

Based on:Sensory dataPrevious knowledgeHypothesis about what is out there

Hypothesis testingNecker cube

Hypothesis testing: Rubins vase

Hypothesis testing

Previous knowledgeRotating masks: http://www.michaelbach.de/ot/fcs_hollow-face/index.html

Previous knowledge

Previous knowledgeWhat shape is this?

Muller-Lyer IllusionWhich one is longer?

Depth cues

Auditory ExpectationsLed Zeppelin Stairway to Heavenhttp://jeffmilner.com/backmasking.htm

Lyrics: Oh heres to my sweet Satan. The one whose little path would make me sad, whose power is Satan. Hell give those with him 666; there was a little tool shed where he made us suffer, sad Satan.

Palmer (1975)

http://www.richardgregory.org/