Slackers? Not So Fast

When aimless 20-somethings drift from job to job and relationship to relationship, they're not necessarily being irresponsible. It could mean that they're simply still learning. Studies from The National Institute of Mental Health (NIMH) suggest that our brains continue to develop until well into our third decade, reports The Wall Street Journal.

Until now, most experts thought that gray-matter maturity came at the end of the teens. But the NIMH researchers have found that the prefrontal cortex—the area of the brain that regulates social behavior and decision-making—is one of the last sections to develop.

The discovery that our brains are still malleable into our late 20s "is the best thing that ever happened to humans," says Dr. Jay Giedd, M.D., of the NIMH. It means that we continue to grow and adapt well past puberty. (Hooray!)

It also helps to make sense of the rise in marriage ages and the career-hopping that characterizes 20-somethings. In fact, these so-called slackers may be on to something: Researchers say postponing major life decisions can help you ultimately make better choices. Which puts a lot of pressure on your 30s.