Primary visual agnosia is called as a rare neurological disorder characterized by total or partial loss of ability to recognize and identify familiar objects and/or people by sight.
This situation occurs without loss of the ability to actually see the object or person.
Visual agnosia also seems to happen when there's brain damage along the pathways which connect the occipital lobe of the brain with parietal or temporal lobe. The occipital lobe then assembles incoming visual information.
The parietal and temporal lobes allow us to understand the meaning of this information.
Symptoms: include difficulty identifying the objects which look similar in shape, difficulty with identifying line drawings of objects, and recognizing objects that are shown from less common views, such as a horse from a top-down view.