When discussing the importance of family and relationships, motherhood entails countless personal sacrifices. Theodore Roosevelt acknowledged as much in 1905, when he told the National Congress of Mothers, "Your duty is hard, your responsibility great; but greatest of all is your reward." While his statement rings true on many fronts, there may yet be one more to explore.

Motherhood has long been considered the embodiment of self-sacrifice, and for good reason. From the first manifestations of "morning" sickness, sacrificial acts consume mothers, body and soul. Of course, it doesn't stop with pregnancy. Every stage of a child's life requires a different set of sacrifices, most of which are made willingly but pass unnoticed by their primary objects. The running joke is that the sacrifices of motherhood run so deep, they even affect the brain: "Insanity is hereditary," goes one adage; "you inherit it from your children." More than one mother has, at one time or another, ruefully (perhaps even proudly) pointed to her children as being responsible for what she considers a decline in her mental capacities.

Fortunately, however, research may have uncovered just the right information to distract us from obsessing about our sacrifices long enough to consider some of the things we might actually be gaining from motherhood.

In this vein Katherine Ellison, author of The Mommy Brain: How Motherhood Makes Us Smarter (2005), brought welcome news to mothers everywhere. It's true, she acknowledges: we mothers have long perpetuated the notion that having babies zaps our brain cells. This notion finally became so entrenched, she informed Vision Media recently, that dozens of scientists set out to discover whether it is actually true. And the truth is? It is not.

In fact, she found, study after study shows that having babies contributes to increased brain cells, and along with these little darlings (the new brain cells as well as the babies) come increased skills of all kinds.

At the center of this life and health study is that now-familiar phenomenon, neurogenesis: the brain's process of growing and changing through the development of new neurons. This amazing brain plasticity is encouraged by repeated new actions, especially of the "positive, emotionally charged, and challenging" variety, referred to by scientists as "enrichment." As it turns out, the process of child rearing, beginning even in pregnancy, is enrichment's mother lode. The abundant variety of intense new experiences forced on us mothers by daily interaction with our children strengthens much more than our flexibility and our multitasking skills. Functional magnetic resonance imaging (fMRI) reveals increases in a long list of areas, including (but not limited to) emotional intelligence, sensory powers, mental perception, motivation, attention, problem solving, prioritizing, memory and learning. And the gains are not temporary. In fact, indications are that the positive changes brought about in the brain by pregnancy hormones, and subsequent stimulation from our babies and children, last for the rest of our lives--long past the time our grandchildren are born.

So why have women almost universally embraced the idea that pregnancy and childbirth turn their brains to jelly? Sleep deprivation certainly plays a role, but Ellison again marshals a long list of neuroscientists whose findings add other crucial pieces to the puzzle. "What's really going on," she translates, is that "a pregnant and early postpartum woman's brain is tied up in a major, hormone-powered transition." In other words, our bodies have just served us a powerful hormonal cocktail designed to prepare our brains for unprecedented growth and reorganization. "Motherhood--" says Ellison, "just like puberty--may knock us off our feet for a time, only to set us back up, often stronger than before." Comparing the forgetfulness of pregnant mothers to Einstein's famous distractedness, Ellison is nevertheless careful to qualify the analogy: "Encouraging as this paradigm may be . . . it's important to remember that new mothers are coping with some serious physical challenges that Albert Einstein could barely have imagined."

Despite the role of pregnancy-induced hormones in this brain-enriching experience, the good news is not only for mothers. Research is hinting that the benefits of child care may turn out to be a "father lode" as well.

Citing research on rodents, Ellison remarks that "modern, engaged dads may be gaining some of the same learning and memory advantages from parenthood as have been found in maternal rats. The key appears to be the degree of involvement with the children." Further, she notes the documented rise of certain "parenting" hormones in men when their wives are pregnant, and points to the well-known phenomenon called Couvades syndrome, in which "sympathy morning sickness" and "sympathy weight gain" are factors.

But are these pre-baby changes only "sympathetic" in fathers? A 2006 study by neuroscientists at the University of Wisconsin-Madison suggests that something physiological is actually occurring. In the first nonhuman primate study into this phenomenon, researchers concluded: "It is clear that expectant fathers of these [primate] species are physiologically responsive to their mate's pregnancy and the impending birth. Males need to be prepared to engage in infant care immediately after birth and this requires carrying multiple infants weighing up to 20 percent of their adult body weight. Both the hormonal and the physical weight change suggest that marmoset and tamarin males prepare for the demands of infant care."

If, as scientists speculate, these physiological changes are brought about by the exchange of pheromones between pregnant mothers and fathers, it may be one more benefit to be gained from the cultivation of close family and relationships.

While adoptive parents and other caregivers also reap some of the brain-boosting benefits of child rearing and also experience some physiological changes, "there is no denying," says Ellison, "that the nine-month preparation of pregnancy and the experience of delivering a child give biological mothers an advantage in making what's usually a life-long commitment."

Ellison's thoughtful collection of research certainly dispatches the sometimes popular notion that raising a child is "less worthy" work for intelligent people. In fact, it's beginning to look like one of the best avenues for becoming a creative human being.

Perhaps motherhood is, after all, its own reward.