Your Brain Doesn’t Reach Adulthood Until 32, According To A New Study

Legally in this country you become an adult at 18, though anyone who has ever been that age and looks back now realizes they were still very much a child. For many of us, we didn’t magically get all our sh*t together in our 20s either. In fact, I think we can all agree your 30s and 40s are when your confidence really settles in, and you feel more grounded and stable in who you are than ever before. Well, a new study published in the journal Nature Communications found that there are five major “ages” in our brains’ lifespans — and the adolescent one lasts until age 32.

Four thousand participants ages zero to 90 underwent brain imaging so researchers at the University of Cambridge could map their brain cells and neural connections, which change constantly throughout our lifetimes. When assessing the images, they noticed five distinct phases of brain development in age ranges that majorly differ from how we define kids, adolescents, and adults. Those brain phases are:

• Childhood: From birth to 9 years old. This is when the brain is narrowing down its countless connections and becoming more efficient.
• Adolescence: From 9 to 32. The brain is working to become incredibly efficient, take in new knowledge, and more. This is also the age range where mental health disorders are most likely to develop, the BBC points out.
• Adulthood: From 32 to 66. This is a long period of stability for the brain where all the change and growth finally slows down. The study suggests brain function peaks in the 30s for most people.
• Early aging: From 66 to 83. The connections in the brain begin to shift and the brain’s sections — each responsible for different functions — become a bit more siloed.
• Late aging: From 83 onwards. This is basically just a time period when the changes of early aging accelerate. This age group had the least data for researchers to analyze because it can be hard to find typical, “healthy” brains in this age group.

The researchers acknowledge that these ages are not hard-and-fast rules. Individual differences, as well as someone’s culture and upbringing can influence their brain’s development. This study is also not trying to say our brains don’t change at all during these age ranges, but rather that the connections throughout them are in sustained phases of either growth or separation. They also did not separate men from women in the study, something commenters on social media posts summarizing the findings were quick to point out.

“I’m convinced this is just an excuse for men to continue to act childish,” wrote one user. “They’ve never needed one,” another replied. But by and large, the comments on Instagram were from women feeling like yes, true adulthood starting later in life tracks with their experience — and they’re kind of hysterical:

• “I AM just a kid. And life IS a nightmare.”
• “The way my mind went ‘well duh.’”
• “For millennials adolescence goes into our 40s I think.”
• “Growing up, my dad always told me ‘you’re not *really* an adult until you’re 35’ so I assumed this was common knowledge.”
• “Honestly this checks out in my experience. Once I was around 30, I legit felt so much more stable.”
• “Guys stop they are going to push the retirement age back.”

Leave it to us millennials to turn a fascinating new study on neutral connections into a meme. But hey, we’re just a bunch of overgrown teens, right? It’s not our fault!