Modelling the Perception of Illusory Contours: Linking Gestalt-Laws and cortical Oscillations

A network for the perception of illusory contours inspired from neurophysio-logical and psychophysical ndings is proposed, incorporating a relaxation phase labeling and diiusion process. The network groups visual features into perceptual entities by (de)synchronising parametric phase labels of simple neuronal oscillators using a constraint satisfaction mechanism. The local constraints between features, which model the Gestaltist grouping principles proximity and good continuation 15, 20], act horizontally in, and vertically between feature dimensions to allow for the emergent segregation of globally salient illusory contours. An initial nonlinear edge detection stage extracts two saliency maps for oriented and orthogonal cooperation between edges and endpoints. The energy maps are rectiied into ON-and OFF-channels which cooperate for nearby ori-entations but compete for orthogonal and opposing directions in phase space suppressing false responses generated from the edge detection stage.