Johns Hopkins Research Award
Study contributes to understanding of normal development
of human visual system
A 21-year-old Johns Hopkins University undergraduate and native of Hopewell, N.J. is playing an important role in discovering how genetic differences may influence how human beings process and understand visual information.
Chinyere Ogbonna's original research, focusing on how the brains of people with a rare genetic disorder called Williams syndrome perceive visual illusions, has been funded with support from a Johns Hopkins Provost's Undergraduate Research Award (PURA). As one of 45 PURA winners this academic year, Ogbonna will present the results of her research at an awards ceremony held at Johns Hopkins on March 10.
Since 1993, about 40 students each year have received PURA grants of up to $3,000 to conduct original research, some results of which have been published in professional journals. The awards, funded through donations from the Hodson Trust, are an important part of the university's commitment to undergraduate research.
Ogbonna recognized that people with Williams Syndrome were so spatially impaired that they could not copy simple patterns as well as the average 6-year-old. Working with Melanie Palomares, a graduate student in the Department of Psychological and Brain Sciences, Ogbonna hypothesized that this was because those with the disorder simply didn't see the pattern accurately.
Working under faculty sponsor Barbara Landau, Dick and Lydia Todd Professor in the Department of Cognitive Science at Johns Hopkins, Ogbonna and Palomares decided to test this hypothesis using something called "visual illusions:" simple pen and ink illustrations that attempt to "trick" the viewer's brain into, for instance, thinking one line is longer than the other. According to the researchers, such illusions are crucial evidence that the normal visual brain sees the world by automatically putting together parts to make an understandable "whole."
With Palomares' help, Ogbonna showed her visual illusion cards to several groups of normal people: 3 to 4 year old; 5 to 6 year olds; 7 to 10 year olds, and adults. She also showed them to people with Williams syndrome who were between the ages of 10 and 41 years old, with an average age of 19.
"We found that when normal people saw parallel lines of equal length that are surrounded by 'railroad tracks' — tilted perpendicular lines — the visual part of their brain tricked them into thinking that the parallel lines were not equal in length," Ogbonna said.
Surprisingly, they found that those with Williams syndrome reacted the same way.
"We were amazed that people with Williams syndrome tested just like normal adults, which is not what we expected, based on previous studies of people with this genetic disorder," Ogbonna said.
Landau, who has studied Williams syndrome for years, calls Ogbonna and Palomares' results nothing less than "brilliant."
"The idea of using visual illusions as the test was just an amazing idea," Landau said. "And the results was very striking and clear. People with Williams Syndrome are severely impaired spatially. They cannot drive a car. They are moderately retarded. The fact that they perform on these tasks the same way that normal, average people do is remarkable, and has the potential to tell us a great deal about how we process and understand visual information. Both Ogbonna and Palomares are brilliant young scientists, with all of the creativity and motivation needed to be successful in life. It's really been a privilege to work with both of them."
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