18 not so adult after all

So you just turned 18 and are now legally considered an adult. In most countries you now have the right to vote, are held legally responsible for binding contracts and criminal actions, and, if a US Citizen, must sign up for Selective Service so that should a national emergency occur you may be drafted into military service in order to protect the country. In all respects but one, a US citizen gains the legal rights and hardships of adulthood at 18. But is one really an adult at 18? Not according to Abagail Baird and Craig Bennet, two Dartmouth researchers who have recently published a study in the journal Human Brain Mapping which shows significant developmental brain changes across the 18th year. The two imaged the brains of nineteen freshmen students and compared them to a control of older students ranging from 25 to 35 years of age, concluding that: "The brain of an 18-year-old college freshman is still far from resembling the brain of someone in their mid-twenties. When do we reach adulthood? It might be much later than we traditionally think." (Bennett quoted in press release)