“I don’t think very young children do think.” If this sounds controversial, it is—psychologist Charles Fernyhough says as much in a Radiolab interview. Fernyhough defines thinking as processing experience through language. That is, for him, thought is largely verbal: what most of us think of as “thinking” involves narrating the world to ourselves as we go through it. He drew the conclusion that little kids don’t think after an experiment showed that children as old as 5 often cannot put together the two verbally-expressed ideas “left” and “blue wall” to grasp the phrase “left of the blue wall”, even when they know what “left” means. Which, to be fair, is a bit shocking.
But so is this: cognitive scientist Ghislaine Dehaene-Lambertz (CNRS—French National Centre for Scientific Research) conducted an experiment last year, where babies born up to 2.5 months premature showed increased brain activity and blood flow in response to spoken language, suggesting that humans, even in utero, are predisposed to learn language, even if they can’t yet make sense of or speak it.
Likewise, babies between 9 and 15 months who were fitted with sensors during playtime showed strong signals in brain areas thought to be underdeveloped during infancy: particularly the prefrontal cortex, which is responsible for planning, executive functioning, and other types of learning.
Recording both baby and adult brains, a team of researchers at the Princeton Neuroscience Institute (PNI) led by Elise Piazza, “collected data from 57 channels of the brain known to be involved in prediction, language processing and understanding other people's perspectives.” The babies were also shown not to be just passive absorbers of adult stimulation, but to provide feedback and even guide adult behavior (an unexpected finding that will be entirely unsurprising to parents). "While communicating, the adult and child seem to form a feedback loop," Piazza said. "That is, the adult's brain seemed to predict when the infants would smile, the infants' brains anticipated when the adult would use more 'baby talk,' and both brains tracked joint eye contact and joint attention to toys. So, when a baby and adult play together, their brains influence each other in dynamic ways."
Another study—whose conclusions border on the uncanny—suggests mothers’ and babies’ brains combine into one “mega network” as information is shared between them. University of Cambridge psychologists used dual electroencephalography (EEG) to observe that, during intimate moments of connectivity, like play, brain waves between moms and babies synced up: they were literally “on the same wavelength.” This was especially true in the presence of positive emotions: eye contact, inflections in a mother’s speech, and responsiveness were all associated with a warm emotional mood that helped babies learn better.
While Fernyhough suggests that the question of whether babies think seems to depend on whether you identify thought with language, the research above indicates that the answer may be much more complicated. After all, it’s not as if language dawns on six year olds over the course of an hour: learning language clearly involves complex thought processes even prior to birth.
This is not to say that Fernyhough doesn’t have a point: mental narration might not start until later in childhood than language acquisition. Still, other fascinating types of thought that don’t match our adult notions of thinking are definitely at play in developing brains. Indeed, if you’re quarantined at home with a small child who’s wheedled an excess of snacks and screen time out of you, it’s hard to imagine that that child doesn’t have the capacity for thought.