Visualizing facial expressions

A related condition to faceblindness is the inability to discern emotions through facial expressions. We can best observe this situation when a stroke leaves a person able to visualize faces but not their expressions. This tells us that different areas of the brain are required if we are to be able to accomplish both tasks.

Of the people who have prosopagnosia, those who are severely effected from birth will not be able to tell expressions for the reason that they do not perceive the parts of the face at all. They look at a face and do not see the features. Consider that when you look at a rock, you may only see the gray mass of it and not even notice all the pits and scratches in the rock.

People with mild prosopagnosia who can learn to tell some faces apart over time may also have trouble with facial expressions. The problem is not so much visualization so much as it is a matter of not learning how to make and understand those expressions. So they may look at a person who is sad and not understand that the person looks and feels sad. A person may look angry, but the faceblind person does not recognize the angry look.