Neural activity in areas V1, V2 and V4 during free viewing of natural scenes compared to controlled viewing

UNDER natural viewing conditions primates make frequent exploratory eye movements across complex scenes. We recorded neural activity of 62 cells in visual areas V1, V2 and V4 in an awake behaving monkey that freely viewed natural images. About half of the cells studied showed a modulation in firing rate following some of the eye movements made during free viewing, though the proportions showing a discernible modulation varied across areas. These cells were also examined under controlled viewing conditions in which gratings or natural image patches were flashed in and around the classical receptive field while the animal performed a fixation task. Activity rates were generally highest with flashed gratings and lowest during free viewing. Flashed natural image patches evoked responses between these two extremes, and the responses were higher when the patches were confined to the classical receptive field than when they extended into the non-classical surround. Thus the reduction of activity during free viewing relative to that obtained with flashed gratings is partly attributable to natural images being less effective stimuli and partly to suppressive spatio-temporal neural mechanisms that are important during natural vision.

[1]  R. Wurtz,et al.  Vision during saccadic eye movements. I. Visual interactions in striate cortex. , 1980, Journal of neurophysiology.

[2]  C. Keating,et al.  Visual Scan Patterns of Rhesus Monkeys Viewing Faces , 1982, Perception.

[3]  J. Movshon,et al.  The statistical reliability of signals in single neurons in cat and monkey visual cortex , 1983, Vision Research.

[4]  R. Desimone,et al.  Visual properties of neurons in area V4 of the macaque: sensitivity to stimulus form. , 1987, Journal of neurophysiology.

[5]  G. J. Burton,et al.  Color and spatial structure in natural scenes. , 1987, Applied optics.

[6]  D J Field,et al.  Relations between the statistics of natural images and the response properties of cortical cells. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[7]  A. B. Bonds Role of Inhibition in the Specification of Orientation Selectivity of Cells in the Cat Striate Cortex , 1989, Visual Neuroscience.

[8]  E. Peli Contrast in complex images. , 1990, Journal of the Optical Society of America. A, Optics and image science.

[9]  D. V. van Essen,et al.  Neuronal responses to static texture patterns in area V1 of the alert macaque monkey. , 1992, Journal of neurophysiology.

[10]  R. Shapley,et al.  Broadband temporal stimuli decrease the integration time of neurons in cat striate cortex , 1992, Visual Neuroscience.

[11]  D. Heeger Normalization of cell responses in cat striate cortex , 1992, Visual Neuroscience.

[12]  D. Tolhurst,et al.  Amplitude spectra of natural images , 1992 .

[13]  William Bialek,et al.  Statistics of Natural Images: Scaling in the Woods , 1993, NIPS.

[14]  H. Wilson,et al.  Spatial frequency adaptation and contrast gain control , 1993, Vision Research.

[15]  M. Segraves,et al.  Primate frontal eye field activity during natural scanning eye movements. , 1994, Journal of neurophysiology.

[16]  I. Ohzawa,et al.  Length and width tuning of neurons in the cat's primary visual cortex. , 1994, Journal of neurophysiology.

[17]  J. Atick,et al.  STATISTICS OF NATURAL TIME-VARYING IMAGES , 1995 .

[18]  Christof Koch,et al.  Temporal Precision of Spike Trains in Extrastriate Cortex of the Behaving Macaque Monkey , 1999, Neural Computation.

[19]  R C Reid,et al.  Efficient Coding of Natural Scenes in the Lateral Geniculate Nucleus: Experimental Test of a Computational Theory , 1996, The Journal of Neuroscience.

[20]  S. Yantis,et al.  Visual attention: control, representation, and time course. , 1997, Annual review of psychology.

[21]  D C Van Essen,et al.  Neural activity in areas V1, V2 and V4 during free viewing of natural scenes compared to controlled viewing. , 1998, Neuroreport.