title: Local stimulus disambiguation with global motion filters predicts adaptive surround modulation.
abstract: Humans have no problem segmenting different motion stimuli despite the ambiguity of local motion signals. Adaptive surround modulation, i.e., the apparent switching between integrative and antagonistic modes, is assumed to play a crucial role in this process. However, so far motion processing models based on local integration have not been able to provide a unifying explanation for this phenomenon. This motivated us to investigate the problem of local stimulus disambiguation in an alternative and fundamentally distinct motion-processing model which uses global motion filters for velocity computation. Local information is reconstructed at the end of the processing stream through the constructive interference of global signals, i.e., inverse transformations. We show that in this model local stimulus disambiguation can be achieved by means of a novel filter embedded in this architecture. This gives rise to both integrative and antagonistic effects which are in agreement with those observed in psychophysical experiments with humans, providing a functional explanation for effects of motion repulsion.
authors.affiliation: Institut de Robòtica i Informàtica Industrial (CSIC-UPC), Llorens i Artigas 4-6, 08028 Barcelona, Spain. bdellen@iri.upc.edu
authors.forename: Babette
authors.initials: B
authors.lastname: Dellen
authors.forename: Carme
authors.initials: C
authors.lastname: Torras
mesh_terms: D006801:Humans; D008959:Models, Neurological; D009038:Motion; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics / Q000379:methods; D014793:Visual Cortex / Q000502:physiology*
keywords: Aperture problem; Constructive interference; Fourier analysis; Global filters; Motion processing models; Motion repulsion; Stimulus disambiguation