Prosopagnosia And The Neural Basis For Facial Recognition
What is actually happening in the brain when one person looks at another?
For people with prosopagnosia, an inability to recognize faces, information processing - the stages that our brains go through to recognize a face - is breaking down.
“We refer to prosopagnosia as a ‘selective’ deficit of face recognition, in that other cognitive process do not seem to be affected,” explains Bradley Duchaine, an associate professor of psychological and brain sciences at Dartmouth. “[People with the condition] might be able to recognize voices perfectly, which demonstrates that it is really a visual problem. In what we call pure cases, people can recognize cars perfectly, and they can recognize houses perfectly. It is just faces that are a problem.”
The condition may be acquired as the result of a stroke, for example. But in a recent Brain study, they focused on developmental prosopagnosia, in which a person fails to develop facial recognition abilities. “Other parts of the brain develop apparently normally,” Duchaine says. “These are intelligent people who have good jobs and get along fine but they can’t recognize faces.”
Famous and non-famous faces used in the prosopagnosia experiment. Paired famous and non-famous faces are shown in corresponding positions. Credit: Bradley Duchaine
The temporal lobe contains a number of face processing areas, so you can imagine there are many different ways that this system can malfunction. Not only can an area not work, connections between areas might not work yielding probably dozens of these different variants of this condition.
This picture is terrifying. Bush is the only one I recognize. I think it’s also worse when there are lots of people because I sort of just get freaked out and overwhelmed and shut down. Because faces are scary.