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Geometric visual hallucinations, Euclidean symmetry and the functional architecture of striate corte

Geometric visual hallucinations, Euclidean symmetry and the functional architecture of striate corte

  1. Crazy Insane Sanity
    "This paper is concerned with a striking visual experience: that of seeing geometric visual hallucinations. Hallucinatory images were classi¢ed by Klu«ver into four groups called form constants comprising (i) gratings, lattices, fretworks, ¢ligrees, honeycombs and chequer-boards, (ii) cobwebs, (iii) tunnels, funnels, alleys, cones and vessels, and (iv) spirals. This paper describes a mathematical investigation of their origin based on the assumption that the patterns of connection between retina and striate cortex (henceforth referred to as V1)öthe retinocortical mapöand of neuronal circuits in V1, both local and lateral, determine their geometry."

    Paul C. Bresslo¡, Jack D. Cowan, Martin Golubitsky, Peter J. Thomas and Matthew C. Wiener