title: Simulation of neural contour mechanisms: from simple to end-stopped cells.
abstract: Early stages of visual form processing were modelled by simulating cortical simple, complex and end-stopped cells. The computation involves (1) convolution of the image with even and odd symmetrical orientation selective filters (S-operators), (2) combination of even and odd filter outputs to a local energy measure (C-operator), (3) "differentiation" of the C-operator maps along the respective orientation (single and double end-stopped operators) and (4) determination of local maxima ("key-points") of the combined end-stopped operator activity. While S- and C-operators are optimised for the representation of 1-D features such as edges and lines, the end-stopped operator responses at the key-points make explicit 2-D signal variations such as line ends, corners and segments of strong curvature. The theoretical need for this complementary representation is discussed. The model was tested on grey-valued images.
authors.affiliation: Communication Technology Laboratory, Swiss Federal Institute of Technology ETH, Zurich.
authors.forename: F
authors.initials: F
authors.lastname: Heitger
authors.forename: L
authors.initials: L
authors.lastname: Rosenthaler
authors.forename: R
authors.initials: R
authors.lastname: von der Heydt
authors.forename: E
authors.initials: E
authors.lastname: Peterhans
authors.forename: O
authors.initials: O
authors.lastname: Kübler
mesh_terms: D005374:Filtration; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008959:Models, Neurological; D012399:Rotation; D014793:Visual Cortex / Q000502:physiology