The Smiley Face Cortex
This past week within the heap of subservient undergraduate tasks that I perform in my research lab, I had the chance to explore an interesting component of the visual system. I work under Dr. Wallace, who is an authority on the subject of multisensory integration within the visual and auditory systems. The project that I am assigned to is trying to discover the differences in multisensory binding within varying stages of development. The general findings show that at younger ages humans will perceive a ‘simultaneous’ event when auditory and visual information are separated over a larger temporal window than in adults. That is a ball can have a sound played after it hits the floor, and because infants have slower neurological processes (less myelin) and less visual experience, a baby will perceive that the sound was generated by the ball hitting the floor.
Look back at the three sentences of ramble that I just wrote, I realize that this seems like a verbose description of a very basic feature of our visual and auditory integration. However, deficiencies within this ability can seriously impair normal interactions and are associated with disorders such as Dyslexia and Autism.
My task was to help design a multisensory experiment to optimize attention among infant subjects by using certain stimuli. Previous studies show that children are more receptive to circles, the color red, and faces. An interesting study done by Teresa Farroni at Duke University, found that among faces, babies specifically prefer dark regions under the eyebrows and nose. During this experiment they tested the infant’s response to normal faces, a face with inverted colors, upside down faces, and crude smiley faces with normal or inverted coloring.
I found this very interesting because this is one way the brain compensates for the visual deficiencies of babies. Because they have slower conductions and less experience in terms of social/ inter-personal interaction, infants inherit a disposition/preference for this basic outline of the human face. This simple shading pattern (essentially a smiley face) represents the two eyes and the mouth. This pattern is recognized by our visual system before our brain is fully developed and before we have socially learned the shape of the face.
Vandy Perceives said,
March 27, 2008 at 7:46 pm
[...] such as ADHD. Priya wrote about how Vision Therapy might help with some people with autism. Karthik wrote about some research he’s involved in concerning infant perception. Spencer wrote about [...]