Moms joke about "mommy brain" and the things it makes us do - leave ice cream in a hot car until it becomes part of the upholstery, search frantically for keys while holding them in your hand, put milk in the pantry and cereal in the fridge, and other feats of forgetfulness and distraction.

But stereotypes about absent-minded pregnant women and new mothers can be harmful, a study at the University of Pennsylvania found. The study participants, MBA students, rated their interactions with a female manager as less satisfactory when they were told the woman was pregnant. At least one psychologist, Dr. Katherine McAuliffe of Harvard, has suggested that we forget terms like "pregnancy brain" altogether.

Lots of recent neurological research has explored the parental brain, and despite what you may have heard about "momnesia," "preghead," or "baby brain," the news isn't all bad. Here are five ways that parenting enhances cognitive function.

1. Mothers' brains undergo a variety of changes that enhance parenting, according to a recent article in The Atlantic. "Gray matter becomes more concentrated. Activity increases in regions that control empathy, anxiety, and social interaction "¦ A flood of hormones during pregnancy and in the postpartum period help attract a new mother to her baby. In other words, those maternal feelings of overwhelming love, fierce protectiveness, and constant worry begin with reactions in the brain," the article reported.

2. Besides increasing in activity, brain structures that are related to parenting actually grow in size after childbirth, according to a study at Yale-New Haven Hospital. Researchers scanned mothers' brains before and four months after childbirth. The brain areas that increased in size affected "support maternal motivation (hypothalamus), reward and emotion processing (substantia nigra and amygdala), sensory integration (parietal lobe), and reasoning and judgment (prefrontal cortex)."

3. Think your baby is the cutest, most amazing baby in the world? The Yale-New Haven study also found that "the mothers who most enthusiastically rated their babies as special, beautiful, ideal, perfect and so on" experienced the biggest brain changes.

4. According to Liisa Galea, a neuroscientist at the University of British Columbia, a woman's brain shrinks by as much as 8 percent during pregnancy but returns to normal size by six months after birth. Rodent studies suggest that, in the long-term, mothers may have enhanced memory and multitasking abilities. "It's like their brain becomes more prepared to deal with the responsibilities of keeping their family safe and organized," Galia said.

5. Caregiving fathers also experience increased brain activity in brain regions related to emotional processing and understanding others' mental states - the region of the brain known as the "parental caregiving network." According to a recent study reported in Science magazine, brain changes increase when fathers spend more time caring for and interacting with their babies.