The structure of the human motion detection system

Unlike technical pattern recognizers, humans are adept at the detection of regions of coherent movements in changing images. Possible physiological mechanisms for this ability are discussed in terms of simple mechanistic models, and the results of psychophysical experiments are presented. These results are compatible with two different mechanistic interpretations. The main result is that the human movement detectors are tuned, and a whole ensemble of mechanisms, tuned to different velocities, reside at any location in the visual field. Thus an observer may easily see two velocity vectors simultaneously at a given place. Segregation occurs when different detectors are stimulated at each side of a border. The spatiotemporal parameters that characterize the units limit the resolution in time and space, whereas sensitivity depends on the number of units that participate in a detection. This number may range between a few (perhaps one) to a thousand or more. Apparently, resolution can be traded against noise immunity. It is argued that technical systems developed on a similar basis might be useful as preprocessors of sequences of images in order to detect features of interest (coherent regions) and to suggest a first rough image segmentation.

[1]  J. Kaas,et al.  Cortical and Subcortical Connections of Visual Cortex in Primates , 1981 .

[2]  V. D. Glezer,et al.  An investigation of spatial frequency characteristics of the complex receptive fields in the visual cortex of the cat , 1976, Vision Research.

[3]  Jan J. Koenderink,et al.  Local structure of movement parallax of the plane , 1976 .

[4]  S. M. Axstis.  PHI MOVEMENT AS A SUBTRACTION PROCESS , 1970 .

[5]  P. G. H. Clarke,et al.  Subjective standstill caused by the interaction of moving patterns , 1977, Vision Research.

[6]  D. Pollen,et al.  Periodic excitability changes across the receptive fields of complex cells in the striate and parastriate cortex of the cat. , 1975, The Journal of physiology.

[7]  J. J. Koenderink,et al.  Temporal properties of the visual detectability of moving spatial white noise , 2004, Experimental Brain Research.

[8]  H K Hartline.  Inhibitory interaction in the retina. , 1969, UCLA forum in medical sciences.

[9]  G. Horridge,et al.  Perception of Movement by the Crab , 1966, Nature.

[10]  L. Maffei,et al.  Correlation between the preferred orientation and spatial frequency of neurones in visual areas 17 and 18 of the cat. , 1982, The Journal of physiology.

[11]  C. J. Keemink,et al.  Gradient detection and contrast transfer by the human eye , 1976, Vision Research.

[12]  D. Hubel,et al.  Sequence regularity and geometry of orientation columns in the monkey striate cortex , 1974, The Journal of comparative neurology.

[13]  L. Maffei,et al.  The visual cortex as a spatial frequency analyser. , 1973, Vision research.

[14]  J. J. Koenderink,et al.  Detectability of velocity gradients in moving random-dot patterns , 1983, Vision Research.

[15]  R. Hetherington.  The Perception of the Visual World , 1952 .

[16]  C Blakemore,et al.  On the existence of neurones in the human visual system selectively sensitive to the orientation and size of retinal images , 1969, The Journal of physiology.

[17]  K. Nakayama.  Differential motion hyperacuity under conditions of common image motion , 1981, Vision Research.

[18]  Patrick Cavanagh,et al.  Image Transforms in the Visual System , 2021, Figural Synthesis.