Effects of amplitude-frequency characteristics of a noise-masked test stimulus on the shapes of visual evoked potentials.
ABSTRACT Visual evoked potentials produced in response to a reversive checkerboard pattern presented in conditions of additive noise were recorded. Changes induced by noise in both the shapes of evoked potentials and the structure of the test stimulus were compared. The nature of changes in the shapes of evoked potentials was found to correlate with the nature of changes in the amplitude-frequency spectrum of the stimulus. These results support the gestalt psychology point of view that the visual system uses spatial frequency rather than discrete means for describing information.
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ABSTRACT: We found a new class of two-dimensional random textures with identical third-order statistics that can be effortlessly discriminated. Discrimination is based on local "granularity" differences between these iso-trigon texture pairs. This is the more surprising since it is commonly assumed that texture granularity (grain) is determined by the power spectrum which, in turn, can be obtained from the second-order statistics. Because textures with identical third-order statistics must have identical second-order statistics (i.e., identical power spectra), visible texture granularity is not controlled by power spectra, and not even by third-order statistics.Biological Cybernetics 01/1979; 31(3):137-40. DOI:10.1007/BF00336998
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ABSTRACT: A numerical Fourier transform was made of the pincushion grid illusion and the spectral components orthogonal to the illusory lines were isolated. Their inverse transform creates a picture of the illusion. The spatial-frequency response of cortical, simple receptive field neurons similarly filters the grid. A complete set of these neurons thus approximates a two-dimensional Fourier analyzer. One cannot conclude, however, that the brain actually uses frequency-domain information to interpret visual images.Journal of the Optical Society of America 02/1979; 69(1):95-8. DOI:10.1364/JOSA.69.000095
Article: Gestalt psychology today.[Show abstract] [Hide abstract]
ABSTRACT: The background of gestalt psychology is traced and relationships of gestalt psychology to physics are indicated. The notion of insight is reformulated. Certain trends in American psychology are not fully approved: "I doubt whether it is advisable to regard caution and a critical spirit as the virtues of a scientist, as though little else counted… . Too many young psychologists, it seems to me, either work only against something done by others or merely vary slightly what others have done before." Human experience in the phenomenological sense requires study. A gestalt view of motivation is presented "in terms of… forces which operate between certain perceptual processes and processes in another part of the brain, where a need may be physiologically represented." With deëmphasis on differences in Behaviorist and Gestalt schools and more emphasis on positive contributions of each, constructive work can be accomplished together. "It would be an extraordinary experience—and one good for psychology." (PsycINFO Database Record (c) 2012 APA, all rights reserved)American Psychologist 11/1959; 14(12):727-734. DOI:10.1037/h0042492