Prosopagnosia the inability to recognize faces

Prosopagnosia is a neurological disorder characterized by the inability to recognize faces. It is also called "facial blindness" or "facial agnosia" (as a subtype of the visual agnosia).

Its name derives from two Greek terms: prosopon (face) and agnosia (lack of knowledge).

Oliver sacks

Oliver Sacks is probably one of the most recognized neurologists in the world. He is the author of the book "The man who mistook his wife for a hat". All his knowledge about neurology has not prevented him from also suffering from Prosopagnosia as is reflected in the following video:

Types of Prosopagnosia

A triple categorization has been proposed for prosopagnosia:

• Aperceptive prosopagnia:  The person who suffers from it has difficulty recognizing that a face is a face. It would be perhaps the most basic and elemental level of prosopagnosia and would probably be related to more general agnosias that affect any visual representation, regardless of whether it is a face or an object..

• Discriminative prosopagnosia: When there are difficulties in recognizing a face from different spatial positions and in different perspectives.

• Identifying Prosopagnosia: The person retains the ability to know if a face belongs to someone they know but would have difficulty identifying who it is. This being the case, if they showed him photographs of relatives and strangers, he would know how to discriminate between them, but nevertheless he could not differentiate his sister from his cousin.

Prosopagnosia and Capgras Syndrome

Occasionally, prosopagnosia has been described as the opposite of Capgras syndrome. People who suffer from this syndrome perfectly recognize the visual representation of their family and friends but believe that they are actually imposters with the same appearance.

How is prosopagnosia acquired?

The main cause of prosopagnosia is injuries caused by a trauma craniocerebral or by infections that affect the Central Nervous System. Even so, cases of prosopagnosia have also been found congenital present from birth.

The prosopagnosia in the cinema

There is a movie called "The face of the murderer " that (without going into assessing its cinematographic quality) tries in a more or less creative way to get the viewer to put himself in the shoes of a person suffering from this disorder. Below you can see the trailer.

More information on prosopagnosia

Below you can see several short videos, interviews and documentaries that I have found about this disorder and have found them interesting.

Prosopagnosia: the non-recognition of faces

Interview with Oliver Sacks (Redes program)