The Face in Your Mind

The "Face on Mars"

When you see a face, what tells you that it is a face?

Humans are good at recognizing faces. We even see "faces" where there are no faces - in clouds, on a piece of toast, a man in the moon. A satellite photo of a mesa in the Cydonia region of Mars has been nicknamed the "Face on Mars." I don't see it as any evidence of extraterrestrial habitation, but just a natural rock formation. But it definitely registers as a face.

Neuroscientists have been studying this ability and it is part of what is labeled as pareidolia. Pareidolia is a psychological phenomenon in which the mind responds to a stimulus (an image or a sound) by perceiving a familiar pattern where none exists

Why do most of us have the ability to tell one face from another, even if the differences are extremely small?

Some rather amazing research from the California Institute of Technology was done with macaques, a genus of monkey. Researchers identified a small group of neurons that they believe specialize in picking out individual features of faces and creating a single image.

The macaques wore EEG caps as they looked at a series of several thousand faces and recorded which neurons were active. They believe they even identified specific neurons that corresponded to different features.

The amazing part is that then working backwards they tried to reassemble faces using the information from firing neurons. They were able to rebuild very accurate versions of the faces that had been viewed. Recognizing faces seems to be a process of breaking faces apart into smaller parts for recognition. We still don't know the whole process. For example, why can we pick out a recognizable face in a crowd?

It seems that the brain’s ability to see faces from random objects is due to "configural processing." Do we always need to put together the components — eyes, nose, ears? Sometimes we just seem to recognize a face when we see it.

What can this research lead to? If researchers could stimulate the right cells in the brain of a blind person, it should be possible to give that person the experience of seeing a face, though they wouldn't actually be seeing someone with their eyes.

Sources and Further Reading
www.npr.org
blogs.discovermagazine.com