Alteration of Visual Cortex from Environmental Asymmetries

Wiesel and Hubel have shown that if normal simultaneous binocular vision is prevented during a period when an animal is particularly sensitive to the nature of its visual input, substantial changes can occur in the visual system1–3. A dramatic extension of the influence of visual deprivation was made a few years ago. Kittens were reared viewing contours of a given orientation, and physiological studies showed that their visual cortical neurones had become tuned to the orientation they had experienced4,5. In a related study, kittens were raised with prisms that caused vertical disparities between the images of the two eyes. Later it was found that the distribution of optimal disparities for which binocular cortical neurones were most responsive had undergone a shift, apparently to compensate for the rearing condition6. There is now an indication that the modifications can occur from an exceedingly brief selective exposure7,8 and recent behavioural data complement the original physiological finding9.

[1]  D. Hubel,et al.  SINGLE-CELL RESPONSES IN STRIATE CORTEX OF KITTENS DEPRIVED OF VISION IN ONE EYE. , 1963, Journal of neurophysiology.

[2]  D. Hubel,et al.  Comparison of the effects of unilateral and bilateral eye closure on cortical unit responses in kittens. , 1965, Journal of neurophysiology.

[3]  D. Hubel,et al.  The period of susceptibility to the physiological effects of unilateral eye closure in kittens , 1970, The Journal of physiology.

[4]  D. N. Spinelli,et al.  Visual Experience Modifies Distribution of Horizontally and Vertically Oriented Receptive Fields in Cats , 1970, Science.

[5]  G. F. Cooper,et al.  Development of the Brain depends on the Visual Environment , 1970, Nature.

[6]  R. Shlaer,et al.  Shift in Binocular Disparity Causes Compensatory Change in the Cortical Structure of Kittens , 1971, Science.

[7]  R D Freeman,et al.  A Neural Effect of Partial Visual Deprivation in Humans , 1972, Science.

[8]  R. Freeman,et al.  Electrophysiological Evidence that Abnormal Early Visual Experience Can Modify the Human Brain , 1973, Science.

[9]  D E Mitchell,et al.  Visual Resolution and Experience: Acuity Deficits in Cats Following Early Selective Visual Deprivation , 1973, Science.

[10]  H. Barlow,et al.  Kitten Visual Cortex: Short-Term, Stimulus-Induced Changes in Connectivity , 1973, Science.

[11]  R D Freeman,et al.  Meridional amblyopia: evidence for modification of the human visual system by early visual experience. , 1973, Vision research.

[12]  C. Blakemore,et al.  Environmental Modification of the Visual Cortex and the Neural Basis of Learning and Memory , 1973, Nature.