Infants can use expectations about the world to rapidly shape their developing brains, according to new research.
A series of experiments with infants 5 to 7 months old shows that portions of their brains responsible for visual processing respond not only to the presence of visual stimuli, but also to the mere expectation of visual stimuli, a type of complex neural processing that was once thought to happen only in adults.
“We show that in situations of learning and situations of expectations, babies are in fact able to really quickly use their experience to shift the ways different areas of their brain respond to the environment,” says Lauren Emberson, who conducted the study at the Baby Lab at the University of Rochester when she was a research associate in the brain and cognitive sciences department.
For the study, researchers exposed one group of infants to a sequential pattern that included a sound—like a honk from a clown horn or a rattle—followed by an image of a red cartoon smiley face. Another group saw and heard the same things, but without any pattern.
The researchers used functional near-infrared spectroscopy, a technology that measures oxygenation in regions of the brain using light, to assess brain activity as the infants were exposed to the sounds and images.
After exposing the infants to the sounds and image pattern for a little over a minute, the researchers began omitting the image 20 percent of the time. For the infants who had been exposed to the pattern, brain activity was detected in the visual areas of the brain even when the image didn’t appear as expected.
“We find that the visual areas of the infant brain respond both when they see things, which we knew, but also when they expect to see things,” Emberson says.
The findings, published in Proceedings of the National Academy of Sciences, could help shed light on neural development in infants’ brains.
“Part of the reason I wanted to establish this type of phenomenon in infants is because I think it’s a really good candidate mechanism for how infants are using their experiences to develop their brains,” Emberson says.
“There’s a lot of work that shows babies do use their experiences to develop. That’s sort of intuitive, especially if you’re a parent, but we have no idea how the brain is actually using the experiences.”
Richard Aslin, co-director of the Baby Lab at the University of Rochester, and John Richards at University of South Carolina are co-authors of the study, which is funded by the National Institutes of Child Health and Development.