Visual blindness

Visual agnosia

Visual agnosia (agnosia = inability to recognize a certain sensory quality), which means that the ability to classify and recognize objects on the basis of visual impressions is impaired or missing. The inability may be limited to a certain kind of object, e.g. one understands that what one sees is a bird, but cannot possibly figure out what kind of bird. However, if you get a sound illustration at the same time, the difficulty ceases.