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Prosopagnosia or the problem to tell faces apart

Imagine, you are invited to a Chinese banquet together with Mr. Li, Mr. Wang, and Mr. Peng. Itīs a very diverting evening. the next day you meet one of them but you are not sure which one of the three he is. Most of us are familiar with this situation. However, if this happens to you with members with close friends or even with your family, then you should continue reading.

This should not excite you but rather arouse your curiosity. Of course, you can recognize people but you do it in a different way as you prefer non-facial characteristics. Therefore this phenomenon is also called face blindness a term which is not correct. Faces as such can be seen in any details such as emotions, gender, attractiveness but you can not tell faces apart. In 1947 Bodamer coined the term prosopagnosia an assimilation of the greek words prosopon (πρόσωπον) meaning face and agnosia (αγνωσία) meaning not knowing or recognizing.

There are several forms of prosopagnosia

  • Best known is the acquired form after brain injuries, insult or encephalitis. The sudden loss of a skill will be recognized immediately.

  • This is not the case in people with the congenital (inborn) form They never learned to recognize people by their faces alone. Like color blind people which are only detected by chance e.g. when picking green strawberries, the prosopagnosics are only noticeable when meeting people in unexpected situations. Many prosopagnosics are aware that they have a problem but not knowing the reason they cannot react adequately when confronted by others as being not interested in some one or being absent-minded. By this way they may suffer to some extend from their anomaly.

  • We could show that the congenital form is almost always inherited. Whenever we looked for familial cases we could find other affected ones in the direct line. We therefore called this form hereditary prosopagnosia Interestingly, initially most of the probands were not aware of other prosopagnosics in their families.

  • There are some hints that prosopagnosia might be also part of a syndrome, e.g. the Asperger syndrome. Hence, we also postulate a syndromic prosopagnosia.

    If you have questions, please feel free to contact us

    Prof. Dr. med. Ingo Kennerknecht
    Vesaliusweg 12-14
    48149 Muenster
    Tel. +49-251-8355412
    Fax +49-251-8355393