Maggie Koerth-Baker reviews Shaun Gallagher’s guide to having scientific fun with your brand-new offspring

Just as I do not recommend the research suggested in the headline, it's likewise a bad idea to withhold affection from your infant in order to see how many months it takes for them to become catatonic. It is also inadvisable to condition your child into having a fear of white, fluffy things.

That said, there's still plenty of science-y fun you can have with a baby. Shaun Gallagher's "Experimenting with Babies" serendipitously showed up at my house about three months before my daughter was born. It's a collection of simple demonstrations that will give you some fun games to play with the small people in your life while, simultaneously, teaching yourself about human intellectual and behavioral development. And nobody has to feel guilty for anything.

Each of Gallagher's science projects is broken down into four parts: The experiment (where he describes what you're going to do to your baby); the hypothesis (where he explains what ought to happen); the research (where he tells you about the science that supports the hypothesis); and the takeaway (which puts the research into the larger context of raising a baby).

The experiments aren't actually experiments, of course. But some of these demonstrations are based on actual experiments that real scientists use to understand how human development works.

Take, for instance, the second experiment, "Baby Blueprints". Ideal for babies up to a month old, this demonstration is meant to draw you into a question that scientists haven't really solved yet — are babies born with an innate understanding of what a face looks like and why it's important, or is this something that they learn (albeit quickly) once they're put into social situations with faces all around.

To test that, scientists run experiments that are very similar to what Gallagher suggests you do with your own baby. Little bitty infants (the younger, the better) are shown images that capture some of the structure of a face, like a triangle with a snowman-esque "eyes" and "nose" of two dots with a centered single dot below them. They're also shown that same pseudo-face, but flipped upside down. Then, the scientists document which image the babies spend more time looking at.

There's a lot of literature on this and many replications of this type of experiment, says Anthony Norcia, a neuroscientist who studies vision and neurodevelopment at Stanford. My daughter wasn't particularly interested in participating in this test at all until she was almost a month old. That's a common problem with young babies, Norcia told me, so these experiments haven't only been done many times, they've been done with lots and lots of babies, in hopes of balancing out the effects of the kidlets who just refuse to demonstrate whether they're interested in faces, one way or the other. Gallagher's book lists references to some of these studies and does a pretty good job of summarizing what scientists have found.

Basically, it boils down to this: Even very young babies seem to show a preference for the top-heavy characteristic of faces — i.e., two eyes on top, but only one mouth and one nose. That may, or may not, be the same thing as a preference for faces, though. Some other studies suggest that it's the top-heaviness, not faces specifically, that attract babies' attention. There's probably something special going on here, Norcia told me. But it might be a mixed thing, where the brain is primed to pay attention to that top-heavy shape and that, very quickly, becomes a preference for the top-heavy faces that are hanging over you, talking in silly voices, from the moment you are born.

What Gallagher's book doesn't include is some of the really fascinating directions that research on facial recognition veers off into once it leaves the hospital nursery. Recognizing that a face is important, showing a preference for right-side-up faces as opposed to upside-down ones, and favoring normal pictures of faces over negative print versions — all of these things are adult behaviors that we find in very young children. But, just because the outside behavior is the same, that doesn't mean the internal functioning is identical.

In recent years, Norcia said, scientists have started looking at what is happening in the brains of babies, children, and adults as they look at faces … and there are some striking differences. It's not well understood yet, but, even though the same areas of the brain are recruited when people of all ages look at faces, those parts of the brain aren't operating in the same way at every stage of life. "With brain measurement you're seeing different patterns of response and changes in timing," Norcia said. "You get the basic competency early, but the detail of execution continues to change."

What this means is that the ability to perceive and recognize faces isn't just an on/off skill that kicks in when you're a baby. Instead, it's a process that starts at birth and continues on — with changes happening all the way through your pre-teen years and, in some studies, even up to age 16. Nobody knows exactly what that means yet, but it could be the case that a kid, say a grade schooler, perceives and understands the details of faces and facial expressions in very different ways than her parents do. And, meanwhile, her baby brother perceives and understands those things differently than she does.

"Faces are very complicated in a way," Norcia says. "At a certain level, you have the first cut — this is a face and that's not. But there are much more subtle distinctions. You have human faces versus animal faces. Man versus woman. Older person versus younger person. We can make these super fine gradations and, by the time we're adults, we're experts at faces."

And it all starts with the simple test of whether your baby is more attracted to something that resembles a face compared to something that doesn't. That's pretty cool. And, ultimately, that's why I think Shaun Gallagher's book is worth picking up. Having a kid, raising a kid, is this long exploration of change and development. There's a temptation, for sure, to use a book like this as a super-fine-grained milestone chart, to go through and check off whether your baby can perform a certain task by a certain age and use that to judge whether they're developing "properly" or whether they're achieving more than the other kids.

Don't do that. Instead, think of this book as a reminder of how much change a little person has to go through on the way to becoming a big person. How they see the world and understand the world is steadily becoming more similar to the way you perceive it. But, in the meantime, their experience can be deeply weird, almost alien. This book can help remind you of that fact and it helps get you thinking about your child's world and trying to understand it more from their point of view, even as they try to understand it more from yours.