So .. the thing is, this is a descriptive account of the biology of the brain. However, I sometimes see the "discourse machine" building narratives around pushing the age of majority later, and I suspect this will get used in ammunition for normative purposes.

Anecdotally I’ve felt this shift over the past few years. I am 33 and have always been a huge proponent of personal growth, change, pushing yourself to be better. In the past few years Ive felt the opposite urge, an urge to accept myself, flaws and all, as the hand I’ve been dealt and I must merely play that hand, not focus so much on what-ifs, etc. Perhaps this is my brain solidifying.

As the authors mentioned, ~30 years is the age many people have kids, and it is already well known that female brain changes after giving birth, for example. The authors didn't research if being a parent can explain a part of the difference (and also if parent brains are any different than childless people brains).

I'm personally curious about this: I'm slightly above 30, I observed significant changes in my behavior recently... and I became a parent this year.

Fascinating study.

The stats warrant some caution, though. The main finding is based on figure 4 [1] and I wouldn't be surprised if the number and location of these 'eras' varied a lot if the authors use 40,000 people instead of 4,000.

[1] https://www.nature.com/articles/s41467-025-65974-8/figures/4

I've always thought that I'm just extremely late to mature. I'm 36 now and haven't really felt like I sort of "get" things until my early 30s. My 20s were full of learning experiences, failures, etc. This really makes a lot of sense to me. It also makes me wonder why the human body rewards young parents when their brains are just simply not fully finished cooking. I couldn't have imagined raising a child at 22 with the way I acted and how important freedom was to me. I would've simply been a miserable father.