Soon after my husband, Yoon, became licensed to fly a drone, he took his aerial camera out for a test run over Scarborough Marsh. All summer long here, people paddle flocks of brightly colored kayaks through the narrow channels that stretch over more than three thousand acres. We occasionally walk across it as a family, along a path built over an old railroad bed that cuts a straight line through the landscape’s soft curves. It is a familiar part of the place where we live. Yet the footage Yoon captured that day made it seem new.

From above, I could see how the great mats of grasses are not uniform and whole but variegated. Blades make up clusters that meet in great swirls and layers, circling pools of water and tracing the curves of rivulets. Smudges of color highlight hummocks of grass or gullies where the water has dried and the sun has crisped the salt that remains. The water becomes the sky, the reflection of puffy white clouds visible through long narrow panes between the grasses. From this vantage point, up is down. Space and time seem indistinct. Big is made up of so much little.

This is what I thought of when I stood outside an MRI room at Yale School of Medicine in February 2020 while a technician captured sequential cross sections of the brain of a young woman, a mother, lying inside the machine. The stop-motion curves of white and gray matter in her cerebrum reminded me of the passing topography of the marshland, the seemingly more amorphous inner structures of the brain like the vast mats of grass, incredibly complex and interconnected if you look at them right.

This is not a perfect metaphor. But it is useful.

A marshland is always in flux. Water perpetually moves salt and sediment, sluicing soil from the banks in one place or depositing it somewhere else. When a storm comes, the change is big. Fresh water floods in from upstream. Or a storm surge brings ocean waves farther inland, where they might literally fold pieces of the marsh upon itself or sweep away chunks from the cliff edge.

The brain is like this, too. In every person, it is always changing, adjusting to the circumstances of life, propelling a person’s behavior and responding to the outcomes. The wiring of the brain is not unlike the grass roots in a salt marsh and the ecological systems that support them, woven into a complex, ever-changing system that is, by nature, adaptable.

Researchers have described pregnancy and delivery as a kind of storm. The hormonal surge of pregnancy is incredible. Prenatal education typically addresses these rising waters in terms of what they mean for maintaining pregnancy and supporting the mechanisms of labor. But these mostly below-the-neck, pregnancy-specific changes are only part of the picture. The massive hormone fluctuations that come with having a child, likely more extreme than at any other point in a person’s life, also go to work in the brain, acting as neurotransmitters or regulating the production of other neurochemicals that alter the way neurons are wired together, setting off a cascade of effects that unfurl over time and that last.

They are a kind of weather front, which passes and leaves behind a still-changing landscape. In a strictly metaphorical sense, they soften the brain so that it can be molded into something different. In a literal sense, they make it more plastic and more responsive to the world around it, which now includes a baby.

The adaptation of the parental brain makes possible the love and understanding so many of us hope to have for our children, and that love can be big and generous and lifelong. But it unfolds with time, and a baby cannot wait to be cared for. At the very start, the parental brain does not rely entirely on love, or at least not the version of it we may know. As the parental brain reorganizes itself, researchers have found, brain regions involved in motivation, salience, and vigilance show heightened activity and connectivity in response to a baby’s cues. At the same time, parents report experiencing intense—obsessive, even—preoccupation with their child.

In the upheaval of that lingering storm, a pattern forms. A goal, even: to capture—and to keep—a parent’s attention. “We always think about the pleasure of parenting,” Helena Rutherford, told me, “and we don’t always think about the drive or the motivation of parenting.” Rutherford is a neuroscientist who directs the Yale Child Study Center’s Before and After Baby Lab, which acknowledges right there in its name that there is a “before” and an “after,” and they are not the same.

Studies in animals and humans have found that brain activity seems to shift over time, to a more regulated state. Parents develop their ability to recognize a child’s cues and predict their needs, and to change course when they make a mistake. Rutherford’s work has suggested they may even get better at regulating their own emotions in the context of caregiving. And at least some of these parental brain changes last, perhaps for a person’s whole life.

But the first task, before all else—the movement of the water to the sea—is attention.

The great poet Mary Oliver urged us to bring children to the woods and “stand them in the stream,” to plant in them a love of nature. “Attention,” she wrote, “is the beginning of devotion.” This is true in parenthood, too.

If I could go back and change one thing about my own transition to parenthood, it might be this: I would make Oliver’s sentiment my motto. Attention is the beginning of devotion. Frame those words. Hang them over the bassinet.

Excerpted from Mother Brain by Chelsea Conaboy (Henry Holt and Company, 2022). Reprinted with permission of the publisher.