Cortical+Blindness

Lesions of the occipital lobes, especially if the entire visual cortex is ablated, result in cortical blindness, such that pattern and form vision is lost.

-Ability to discriminate only between different fluexes in luminous energy, i.e. lightness and darkness If damage is restricted to the occipital lobe of only one of the hemispheres, patients will lose patterned vision for the opposite half of the visual field (i.e. a hemianopsia). This is not the same as unilateral neglect or inattention. However, if the lesion is sufficiently large and involves the right parietal area as well, the patient may suffer from both hemianopsia and neglect.
 * Symptoms **

If only a portion of the visual cortex is destroyed, vision is lost only for the corresponding quadrant of the visual field (referred to as a scotoma). In cases of partial cortical blindness, patients are able to make compensatory eye movements and are not terribly troubled by their disability. Indeed, frequently patients have no awareness that they have lost a quadrant or even half of their visual field. Hence, this must be tested for.

They may also exhibit a denial of blindness