A brain-imaging study has offered new support for the notion that infants can accurately track other people's beliefs, and they have the ability to know other people's mental states.
The study at the University of Illinois (UI), posted on the university's website Monday, showed that when seven-month-old infants viewed videos of an actor who saw, or failed to see, an object being moved to a new location, they had changing activities in a brain region known to play a role in processing others' beliefs, just like adults watching the same videos.
"This suggests that the infant brain, like that of adults, may distinguish when others hold true and false beliefs," said UI psychology professor Daniel Hyde, who led the study.
UI researchers used the same brain-imaging methodology of looking at activity in the temporal-parietal junction (TPJ), a brain region thought to play a role in theory of mind, as previous studies used in adults, to look at infants who watched the same videos the adults had seen of an actor watching or not watching a puppet move a toy from one location to another.
Meanwhile, the researchers used an emerging technology called near-infrared spectroscopy, a method that allows infants to sit on their parents' lap and watch whatever presented to them with just a specific cap to capture their brain activity in the TPJ.
They found that the TPJ in infants responds very similarly to that of adults when viewing different video scenarios.
"The infants, like the adults, had an uptick in activity in the TPJ when watching a scenario where the actor failed to observe where the puppet put the toy and, therefore, held a false belief about the location of the toy," he said.
Hyde said the new findings do not suggest that infants have a fully developed theory of mind in the first year of life. "This simply provides a foundation for developing a deeper understanding of other people's thoughts and beliefs."
The findings have been published in the Journal of Neuroscience.