A baby’s brain appears hardwired for the specialized tasks of seeing faces and seeing places at as young as six days old, brain scans of newborns reveal.
The findings offer the earliest peek yet into the visual cortex of newborns, using harmless functional magnetic resonance imaging (fMRI), researchers report.
“We’re investigating a fundamental question of where knowledge comes from by homing in on ‘nature versus nature,'” says Daniel Dilks, an associate professor of psychology at Emory University and senior author of the paper in the Proceedings of the National Academy of Sciences. “What do we come into the world with and what do we gain by experience?”
“We’ve shown that a baby’s brain is more adult-like than many people might assume,” says Frederik Kamps, who led the study as a PhD candidate. “Much of the scaffolding for the human visual cortex is already in place, along with the patterns of brain activity, although the patterns are not as strong compared to those of adults.” Kamps has since graduated from Emory and is now a postdoctoral fellow at MIT.
Baby brain scans
Understanding how an infant’s brain typically organizes may help answer questions when something goes awry, Dilks says.
“For example, if the face network in a newborn’s visual cortex was not well-connected, that might be a biomarker for disorders associated with an aversion to eye contact. By diagnosing the problem earlier, we could intervene earlier and take advantage of the incredible malleability of the infant brain.”
For decades, scientists have known that the adult visual cortex contains two regions that work in concert to process faces and another two regions that work together to process places. More recent work shows that the visual cortex of young children differentiates into these face and place networks.
In a 2017 paper, Dilks and colleagues found that this neural differentiation is in place in babies as young as four months.
For the current paper, the average age of the newborn participants was 27 days. “We needed to get closer to the date of birth in order to better understand if we are born with this differentiation in our brains or if it’s molded by experience,” Dilks says.
Dilks adapts fMRI technology to make it baby friendly. The noninvasive technology uses a giant magnet to scan the body and record the magnetic properties in blood. It can measure heightened blood flow to a brain region, indicating that region is more active.
Wrapped in ‘super swaddlers’
Thirty infants, ranging in age from six days to 57 days, participated in the experiments while sleeping. During scanning, researchers wrapped them in an inflatable “super swaddler,” a papoose-like device that serves as a stabilizer while also making the baby feel secure.
“Getting fMRI data from a newborn is a new frontier in neuroimaging,” Kamps says. “The scanner is like a giant camera and you need the participant’s head to be still in order to get high quality images. A baby that is asleep is a baby that’s willing to lie still.”
To serve as controls, researchers scanned 24 adults in a resting state—awake but not receiving any particular stimulation. The scanner captured intrinsic fluctuations of the brain for both the infants and adults.
The results showed the two regions of the visual cortex associated with face processing fired in sync in the infants, as did the two networks associated with places. The infant patterns were similar to those of the adult participants, although not quite as strong.
“That finding suggest that there is room for these networks to keep getting fine-tuned as infants mature into adulthood,” Kamps says.
“We can see that the face networks and the place networks of the brain are hooked up and talking to each other within days of birth,” Dilks says. “They are essentially awaiting the relevant information. The next questions to ask are how and when these two functions become fully developed.”
Additional coauthors are from Emory. Emory College, the National Eye Institute, the Emory HERCULES Center, the National Science Foundation, an Eleanor Munsterberg Koppitz Dissertation Fellowship, and an NARSAD Young Investigator Award funded the work.
Source: Emory University
Caption: “We can see that the face networks and the place networks of the brain are hooked up and talking to each other within days of birth.”