When my son was a newborn, he slept in the middle of the daytime action. On the couch or glider in the living room, the floor, in our laps, or with the bassinet carted into the thick of things.
I always assumed his little brain was in dream land. But it turns out he was registering the action around him the whole time.
In a study in this month’s Current Biology, researchers used silent scanners to monitor the brain activity of infants while they slept. It turns out, babies are busy taking in a lot of information about the noises and emotions from the people around them — all while fast asleep:
The researchers found that when the babies — ages three to seven months — heard human voices making sad, happy, or neutral sounds. It turns out that the babies’ brains showed activation in areas like the medial frontal gyri and middle temporal gyri — patterns that looked very similar to how adult brains respond to emotional input when were awake.
Sad voices and crying made the insular cortex and gyrus rectus of the babies’ brains become highly active. Again, this is just what happens to adults when we’re awake and hearing crying or sadness.
It’s fascinating to speculate as to why babies would register so much human emotional input when they’re asleep — is it evolutionarily adaptive for little ones to be aware of what’s going on with the people around them at all times?