Remembering Faces
Definitions
Prosopagnosia
The inability for one's brain to remember people by their faces
Facial Fusiform
A part of the underside of the brain that is used in recognizing faces
Summary
Most people can remember someone's face with one glance. However, that is not the case with everyone. About 2% of the American population, who are affected by prosognosia, cannot commit to memory, others' faces. It is not a widely known or widely studied symptom since most with prosognosia tend to try and make up for their condition, but it is often also tied with other difficulties, such remembering and recognizing shapes. For normal people, it is suggested that we remember the mathematical proportions to other peoples' faces instead of their actual face images, since people can remember many faces with just one look. So if some trait of a certain person is exaggerated, then people might recognize them still, even if it is a cartoon with the certain spaces within the face.
An experiment was conducted, by showing normal and affected people distorted faces for five seconds. A Dan and anti-Dan, two extremely long and short faces, and a Jim and anti-Jim, two round and thin faces. For normal people, those who had seen the "anti-Dan" face was more sensitive to the "Dan" like face, and vise versa, but they would not remember the "Jim" style faces as well. With the affected people, there was one person, JM, who received prosopagnosia after a head injury, and they ran the same test with him. There was no effect with showing him the "anti-Dan" face to help remember the "Dans," since he recognized those no more than he did "Jims." However, when the people who were face blind at birth were tested, they did as well as unaffected people at this test. The scientists concluded that even if some people were born that way, they still had some sense of face spacing.
By scanning patients' brains during their face recognition tests, there was one part of the brain that was used up; it was the same part of the brain that JM had damaged. The facial fusiform was still active in those born face blind, but it was discovered that those had less nerve bundles in that section of the brain. However, this is not the only thing that affects prosopagnosia, and it is uncertain exactly which things cause this symptom.
Discussion
I liked this topic since it (was related to neuroscience :P) discussed a topic that scientists and other people have little knowledge about. It was interesting to read about another symptom caused by damage or differences in one part of the brain, since that seems to cause more than one effect. This might explain why some people aren't as good at remembering faces compared to others.
Questions
Do less nerve bundles in the facial fusiform correlate with the inability to remember faces directly, or is there something linked to that area that actually causes this?
Did the JM person damage more of his facial fusiform than the naturally born prosopagnosic people so that he couldn't tell the facial spaces at all?
Citations
Zimmer, Carl. "The Brain." Discover Jan. 2011: 12-13. Science Resource Center.
Web. 8 Jan. 2011.
Web. 8 Jan. 2011.
It's interesting that some diseases act different if born with or acquired later in life. There seems to be a disease for everything, even though with some people, they just can't remember faces because of bad memory :). That shows that the brain is really very complex; there are so many possibilities of deformities or diseases, some that greatly affect peoples' lives and some that don't. Cool topic!
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