Prosopagnosia

Prosopagnosia, also called face blindness,1. Joshua Davis,"Face Blind," Wired, Nov 1, 2006, accessed Feb 13, 2016, http://www.wired.com/2006/11/blind/ is a condition where a person cannot recognize faces, even their own. 

Prosopagnosia is not curable or treatable. People with prosopagnosia never develop the ability to recognize faces. They may learn to rely on other physical features (like eye color, hair color, height, and build) to recognize people.

The opposite of prosopagnosia is the skill of superior face recognition ability.  People with this ability are called "super recognizers".

 Acquired vs. inherited 
Face blindness can be caused by an injury to the temporal lobe of the brain. This is called acquired prosopagnosia. Scientists originally believed this was the only type of face blindness.

Research now shows that there is a developmental or congenital (inherited) form of the disorder. Its prevalence in the general population is 2.5%, which is relatively high. 

 Perception 
Face blindness demonstrates that a person's perception and their picture of the world are built up by various brain systems. This usually works seamlessly and automatically, and we do not notice how it is done. In reality, there are many brain mechanisms which normally work together, tying the visual scene to memory so that we recall vital information.

Causes
Inherited face blindness is present at birth, possibly because of a dominant gene mutation. This mode of inheritance explains why HPA is so common among certain families.

Acquired face blindness can be caused by lesions (damages or changes) or nerve damage in the lower part of the brain,carbon monoxide poisoning, encephalitis (inflammation of the brain), Parkinson's disease, and Alzheimer's disease.

 Diagnosis 
Doctors can check patients for prosopagnosia by using PET and fMRI scans to see if their brain reacts when they see faces.

 Related pages 

 Alexithymia
 Amnesia
 Prosopamnesia
 Super recognisers

References

Category:Vision
Category:Developmental disorders
Category:Face
Category:Memory
Category:Genetic disorders