Recently, I was catching up with a friend who had just given birth to her first baby. I thought about all of the changes I had experienced since having my 1- and 3-year-old daughters. “I feel like I am a completely different person,” I said.

As soon as the phrase came out of my mouth, I questioned it. Nearly 2 billion people in the world are mothers. Surely they didn’t all feel completely different after giving birth. Or did they?

Most people are familiar with the term “mommy brain,” a phrase that describes the brain fog and forgetfulness that many pregnant women and new moms experience. But it turns out there’s way more going on than just forgetting the name of your college professor, and it’s something called matrescence.

Coined by medical anthropologist Dana Raphael in 1973, matrescence is, quite simply, the process of becoming a mother. It’s an immense physical, psychological, emotional, and social shift—and one that’s far more intense than most people realize.

“When I was pregnant with my first child, I thought pregnancy was a one-time, transient hormonal event, and that when [my daughter] was born, I would just go back to myself,” says Lucy Jones, a journalist and author of Matrescence: On the Metamorphosis of Pregnancy, Childbirth and Motherhood. “But that’s just not what it is at all. It’s actually the most dramatic, seismic, endocrinological, and neurobiological experience you can have in adult life.”

Major changes are at play

Although it’s common knowledge that women undergo massive hormonal shifts on their way to becoming a mom, there’s been a lack of research into new moms’ brains until very recently. But several groundbreaking neuroscience studies have been published in the past few years, Jones says. showed that pregnancy leads to significant structural and functional changes in the brain, while demonstrated alterations to gray matter in certain areas of pregnant womens’ brains. (Interestingly, these changes persisted for years after childbirth.)

Countless other changes are happening too, though they’re harder to quantify. Ask any new mom if she feels like some of her relationships with family and friends have changed since having kids, and she’ll likely say yes. There are also pronounced physical changes—like embracing new postpartum bodies that function differently, whether that means pelvic floor problems, hair loss, or weakened abdominal muscles. Plus, there are emotional changes, like a newfound and over our children.

During the early postpartum period, there’s an immense learning curve. Although this phase can feel overwhelming, suggests that if the cognitive challenges present during this time are continued across someone’s lifespan (meaning someone is actively parenting for many years), it can actually be beneficial for brain health later in life. “What we know about the brain is that novelty and complexity and cognitive challenge are very stimulating,” says study author Edwina Orchard, a postdoctoral research associate at the Yale Child Study Center at Yale University. In other , Orchard has even shown that the more children someone has parented, the younger their brain looks—and that middle-aged parents actually have than their childless counterparts.

That suggests a neuroprotective effect of parenthood on brain age. Other has shown moms’ brains change to varying degrees, says Orchard, who also works at the , a research group at Yale. “Mothers who experience more pronounced changes also show more sensitive caregiving behaviors,” she says. “They have better attachment or more positive feelings about their child.”

Stronger than before

“Mommy brain” is a real thing, particularly when it comes to . But the idea that new moms undergo some sort of early onset dementia during matrescence is misguided, says Abigail Tucker, author of Mom Genes: Inside the New Science of Our Ancient Maternal Instinct.

Experts believe the cognitive deficit many pregnant women and new moms face when they forget someone’s name or put the cereal in the fridge could very well be the result of , Tucker says. Or, it could simply be from the shift in focus that new moms are experiencing.

“All of a sudden, the new mother’s thoughts revolve around a tiny person who didn’t exist a few months or even minutes ago, and everything else falls by the wayside,” Tucker says. “Perhaps there is temporarily less brain power left over for other stuff that suddenly seems so much less important, like remembering to mail a letter.”

I was definitely sleep-deprived, forgetful and absentminded during pregnancy and the early postpartum period. (My older daughter used to ask me why I was spacing out so much). But I had this innate sense that I’d also become mentally sharper in many ways. It turns out I was onto something.

Research has shown pregnant women and new moms are better at and reading , Tucker says. They’re and even better at , possibly to detect potentially harmful foods. They can also be surprisingly calm in stressful situations: One found that women late in pregnancy rated an earthquake in California as less stressful than other survivors.

All parents—not just moms—undergo a neural transition

Moms aren’t the only ones who experience a major identity shift when they become parents.

“Science is showing that, particularly with hands-on, affectionate care, spending time with a child affects a father or a non-biological parent’s hormone levels, shape of the brain, anatomy of the brain, and response to the baby,” Jones says.

found the degree to which a new father’s testosterone and cortisol levels changed when his baby was born could predict how involved he’d be with his child later on. found that very involved dads experienced more activation in the amygdala, the area of the brain responsible for decision-making, instinct, and the fight-or-flight response. also suggested foster mothers experience similar oxytocin changes as gestational mothers when bonding with their babies.

Increased awareness

Experts believe matrescence is as significant of a transition as adolescence. Yet the term matrescence (which doesn’t even appear in the Merriam-Webster dictionary) still hasn’t gained much traction in the 50 years since it was coined.

“Everyone knows adolescents are uncomfortable and awkward because they are going through extreme mental and bodily changes,” Jones writes in Matrescence. “But, when they have a baby, women are expected to transition with ease—to breeze into a completely new self, a new role, at one of the most perilous and sensitive times in the life course.”

More research on matrescence is being done each year. Historically, perinatal mental-health researchers thought it was important to study moms for the sake of their babies, says Sheehan Fisher, a perinatal clinical psychologist at Northwestern Medicine. “Now, we’ve shifted so that moms’ mental health matters in and of itself.”

More awareness about the changes women go through during this time can be beneficial on both an individual and societal level. Perinatal mental health conditions are —one in five women experience one during this vulnerable time—plus the majority of new moms in the U.S. to paid maternity leave.

“I think our understanding of this as a sensitive period should be positioned as strongly as possible to encourage governments to federally mandate paid parental leave for all new parents, not just birthing parents,” Orchard says. “Not just as a physical recovery from birth, but as an acknowledgement of the huge environmental and behavioral identity shifts that are happening through this time.”