Disturbances of Vision by Cerebral Lesions

Abstract

-Col. R.A.M.C. ABOUT 18 months ago I was able to present to this Section with my colleague, Colonel Lister, certain clinical observations on the disturbances of vision produced by gunshot injuries of the visual cortex and of the optic radiations. From these we drew certain conclusions on the cortical representation of the retina, and particularly on the segmental correspondence of different areas of the retina with separate zones of the visual cortex. Our chief conclusions were:1. The upper half of each retina is represented in the dorsal, and the lower in the ventral part of each visual area.2. The centre for macular or central vision lies in the posterior extremities of the visual areas, probably in the margins and the lateral surfaces of the occipital poles. The macular region has not a bilateral representation.3. The centre for vision subserved by the periphery of the retinae is probably situated in the anterior ends of the visual areas, and the serial concentric zones of the retina from the macula to the periphery 'Read in the Section of Ophthalmology of the Royal Society of Medicine, December 12, 1917.

Changes in volume, surface estimate, three-dimensional shape and total number of neurons of the human primary visual cortex from midgestation until old age

“…The classic representation of the visual field on the human striate cortex (Holmes and Lister 1916;Holmes 1917) was recently reviewed (Horton and Hoyt 1991). By correlating magnetic resonance scans with homonymous field defects in patients with clear lesions of the occipital lobe, it was found that the cortical extent devoted to central vision was greater than previously described, 2.5 ~ corresponding to 30%, 10 ~ to 50% and 30 ~ to 83% of the surface of the primary visual cortex.…”

Computational Modeling of Responses in Human Visual Cortex

“…Visual cortex was localized rather early, though not without some serious disputes (Phillips, Zeki, & Barlow, 1984;Munk, 1881;Zeki, 1993). The biologists were joined in the late nineteenth and early twentieth centuries by neurologists and ophthalmologists (Inouye, 1909;Henschen, 1893;Holmes, 1918;Holmes & Lister, 1916). The clinicians treated soldiers who had occipital head wounds that caused blindness in restricted regions of the visual field.…”

Type 2 blindsight and the nature of visual experience

“…Several of Riddoch's subjects described their experiences of moving stimuli in their blind fields as 'shadowy' (Riddoch, 1917). Gordon Holmes's (1918) subject 11 reported awareness of moving white stimuli but described them as seen 'through a mist', and as having a 'dirty grey colour'. GY has described his experiences of moving objects as that of a normal person, with his eyes shut, who looks out of the window and moves his hand in front of his eyes (Barbur et al, 1980) and as that of 'a black shadow moving on a black background' (Zeki & Ffytche, 1998).…”