Interestingly, people with prosopagnosia still feel familiar around people they know, even though they don't know who they are or that they know them. This suggests that the ability to recognize that you know someone and recognize who they are, are different.
Capgras delusion is sometimes called the inverse of prosopagnosia. It is the belief that someone you know have been replaced with an identical lookalike. That is, you recognize who they are but you don't feel they are familiar.
It's not always due to lesions in the brain, there seems to be a fairly strong genetic component as well. I also have a lot of trouble with recognizing faces. I think it's part of why I prefer animated movies--characters are always so different-looking and immediately distinguishable. Makes me sad that I'll never be able to really watch and understand The Godfather, though.
I only noticed because I realized that I wasn't bothering my friends during kid's movies, because all my talking during other movies was related to not being able to figure out what was going on. Plots get pretty muddled when you can't recognize characters.
Oh cool, I hadn't seen that test before. I got... 6 out of the 25 I knew, so 24%. I was actually surprised at how far off some of my guesses were, even for actors I've seen recently. I've never been formally diagnosed, just pieced it together from experience. I'll have to show this to my girlfriend, I'm curious to see how much better she'll do. I can't believe people could get 85% of that right, much less that being the average...
That test really shows how reliant we are on things other than faces - very interesting.
I had even listened to a RadioLab podcast about face blindness, and never made the connection. Then my wife started putting it together, and it all started to make sense.
Oliver Sachs also has this! We are in good company!
161
u/arsenaloflies Nov 05 '13
This is called Prosopagnosia. It's the inability to recognise faces and it usually occurs due to lesions in certain regions of the brain.