National Science Foundation grant will help scientists study how hearing levels and early-language experience influence deaf children's vision
Does being born deaf lead to better visual skills, or does a lack of hearing make it difficult for deaf children to pay attention to the world around them? According to researchers at Rochester Institute of Technology's National Technical Institute for the Deaf, who recently earned a $450,000 National Science Foundation grant, the answer often depends on the background of the deaf child being studied.
The NSF award, which will be distributed over three years, will support a longitudinal study of 150 deaf children, ages 6 to 13, attending schools for the deaf around the United States. The research team, led by Matthew Dye, assistant professor in NTID's Department of Liberal Studies, and Peter Hauser, professor and director of NTID's Deaf Studies Laboratory, hopes to prove that deaf children who learn American Sign Language (ASL) early in life look at the world differently compared to deaf children who receive a cochlear implant and use a spoken language such as English. They also hope to learn whether it is a lack of hearing or the age at which they are exposed to a natural language that most influences how deaf children perceive the world.
Through assessments of each child's hearing levels, cognitive skills and fluency in ASL, the scientists will determine how well these variables predict deaf children's improvements in processing visual information. Research will also focus on how well deaf children can shift their focus of attention from one thing to another, or temporal visual attention. Using a set of iPad games, deaf children will be asked to look for targets in fast-moving streams of visual information or pick out important sequences.
"Many people think that being born deaf leads to deficits in the ability to understand information that is presented sequentially," said Dye. "However, previous research has failed to dissociate loss of hearing from exposure to language. In this study, we want to see whether early exposure to ASL can enhance sequence processing in deaf students."
Dye has said past studies have looked only at deaf children born to deaf parents, and who learned ASL when they were infants. Other studies have looked only at deaf children born to hearing parents, who do not learn ASL and use speech to communicate alongside digital hearing aids or cochlear implants.
"The visual attention system consists of different cognitive networks; language and hearing levels appear to have a positive effect on some, but not all, aspects of the network," Hauser explained. "These findings have been based on comparing deaf individuals of different ages and backgrounds. With this grant funding, it is exciting that we now can follow the same deaf children over a period of time to observe how early language experience may lead to these changes."