Visual agnosia was first identified in 1890, and it refers to the patient's inability to recognize people and objects using sight alone. Some patients may have a total loss of visual recognition, and others may be only partially affected. The type of visual agnosia associated with posterior cortical atrophy is known as secondary visual agnosia. Patients with this form of agnosia may be unable to recognize pictures of identical objects taken from different angles, and they may have difficulty drawing a picture of a familiar object. Some patients might be unable to state how objects they see in photos are normally used. Patients with this ailment often use touch, smell, or sound to identify objects, and they may identify others based on how they walk or talk. Medications used to treat Alzheimer's disease may help patients with posterior cortical atrophy in identifying objects and people more easily. Sometimes, patients might choose to have rehabilitation that re-teaches them about commonly used objects, and therapy used to restore lost memories may also be beneficial.