[W]hat exactly happens in the brain when we gaze at a baby? And why do we respond the same way to the offspring of other animals?
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“[C]ute babies essentially have a very quick and privileged way of entering our consciousness. They grab our attention so quickly that you are not yet conscious of it – after a seventh of a second of seeing a baby, you get this wave of brain activity that says ‘Woah, that’s a baby! I need to care for it!’” [says neuroscientist Morten Kringelbach.]
Researchers have even developed a cuteness rating system based on objective measurements including the proportion of forehead to overall face, cheek chubbiness, and how big the eyes are.
Well, on average, puppies and kittens scored higher on this scale than humans… One answer is that humans have had immense control over the evolution of domesticated cats and dogs, changing their appearance over generations through selective breeding.
“Animals like dogs and cats have been essentially bred to look like babies,” says Kringelbach. “They have the big eyes, they have the big ears. When you see them, your brain is thinking ‘this could be a baby’. And it’s only later on, by the time you already have reacted, you say ‘oh, that’s not a baby. But maybe I should still look anyway!’