This monograph on psychic blindness is based on a study of the literature and on experience of 415 personal observations of posterior hemispheric lesions. It is divided into three parts: (1) evaluation of conceptions of optic agnosia; (2) anatomoclinical study of methods of examination and semiology of visual agnosias, description and analyses of personal material, relations between the symptoms and statistical correlations, and anatomical conditions; (3) present conceptions concerning optic agnosia and the agnostic phenomenon. There is a brief bibliography.
As a result of their study the authors isolate two groups, one of which is characterized by unilateral spatial agnosia and other correlated forms of spatial agnosia, the other by agnosia for objects and figured images and the statistically correlated agnosia for symbolic images. The first group can perhaps be extended also to agnosia for physiognomies and the second group also perhaps to agnosia for colors, but the number of