A new study has found that sighted infants born to blind parents make less eye contact with adults in general, but otherwise tend to develop normally, and even excel, in memory and visual attention skills.
The findings show that babies born to blind parents are actively learning and adapting to their situation, seeking the best route to communication.
Eye gaze is an important channel for communication, and human infants show an amazing ability to recognize and react to adults’ gaze. The researchers wanted to investigate how infants develop their attention to the eyes when their primary caregiver is unable to make eye contact or react to an infant’s gaze because they can’t see.
“Infants of blind parents allocated less attention to adults’ eye gaze,” said researcher Atsushi Senju, Ph.D., of Birkbeck, University of London. “It suggests that infants are actively learning from communicating with their parents and adjusting how best to interact with them.”
Senju said it’s important to note that these babies developed typical overall social communication skills, suggesting that the patterns of difference the researchers observed were limited specifically to the babies’ attention to adults’ eye gaze.
For the study, the researchers used eye-tracking technology to follow the gaze of 14 sighted infants of blind parents at six to 10 months and then again at 12 to 16 months of age. They also observed the babies interacting with their blind parent and with an unfamiliar sighted adult.
In comparison to a group of infants with sighted parents, those whose parents were blind paid less attention to adults’ eyes, the researchers report. The babies with blind parents were otherwise typical in their development, and in some areas, they even excelled.
“Infants of blind parents showed advanced visual attention and memory skills when they are eight months old, which we did not expect when we started this project,” Senju said.
He said that perhaps the need to switch communication modes between blind parents and other sighted adults might boost infants’ early development of visual attention and memory.
The researchers are still unsure just how long these differences will last in infants born to blind parents. It’s possible the communication differences might diminish as children interact more with peers and other sighted adults. They are now following up on these children at the age of three to study their longer-term development.
In upcoming studies, they would like to investigate development in another interesting group of babies: the hearing infants of deaf parents.
The findings are published in the Cell Press journal Current Biology.