Like most such things, I'd expect this to be a spectrum, and I may be somewhat of a late bloomer. Regardless, I have a theory that there is somewhat of a protective effect operating here. Believing in a simpler reality which involved future wish fulfillment for me - however unrealistic it was - may have helped me survive. Coming to acceptance of what I see as a more accurate but far bleaker perspective required me to grow strong enough to sustain my will to live despite that perspective.

Biggest lesson learned: I could not do it without at least one other person (or more) who I trust almost 100% with all of myself. Realizing that going it alone is futile is definitely part of what I consider becoming an adult, and it can take a long time to fully accept that.

1. Infancy --- The Moon. Since the Moon waxes and wanes more rapidly than any other celestial object, this period is characterized by the fastest development.

2. Childhood --- Mercury. As Mercury is the fastest of the planets, at this age children have the short attention spans and flit from one thing to the next.

3. Youth --- Venus. Starting around puberty, a man's mind starts to become focused on love.

4. Young Adulthood --- The Sun. A man comes of age, he starts to think about his work and people begin to take him seriously.

5. Middle Adulthood --- Mars. In his mid 30s a man's demeanor becomes more severe. He realizes he has certain goals he would like to accomplish and there is not much time left to achieve them.

6. Maturity --- Jupiter. By his mid 50s, having achieved what he can in his life, he has arrived at a position of authority in the community. He has gravitas and respect.

7. Old Age --- Saturn. By his late 60s, he starts to decline physically and mentally.

>From 32 years, the brain architecture appears to stabilise compared with previous phases, corresponding with a “plateau in intelligence and personality” based on other studies. Brain regions also become more compartmentalised.

--

I felt this 32-year-old shift, but later (now 43). I joke with friends that I was a bone-head like most males until about 30. Joke yes, but feels right.

Prior to 30ish, I was more insecure. Lacking in emotional intelligence. My conclusions from my experience, not projections from what I've read about that time.

My career and relationship history reflect that switch-flip in a way. Only during the second half of my 30s did I begin to feel more secure and more confident in my career, despite not achieving some outrageous senior position or level of income. That career is now in a better and more measured place - in which I recognize what I do well and what I don't do well, and don't beat myself to a pulp for not having "it"

Only in my 30s did I robustly embrace the power of compromise in friendships and relationships. Now I'm near 10 years married (and happy, most of it, let's be real) with two wonderful kids.

And now I'm much capable of reasoning with my anxities, emotions, and insecurities. Do I still ruminate? Yes. Do I still react? Yes. But I know how to redraw situations to reset my in-moment feelings and/or avoid unecessary negative action.

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.

There was no special event in my life that kickstarted this, it was tge beginning of a more mature way to look at things & people. I started to see some repeated events & behaviours that I had already experienced and this also contributed to have a more tempered way to manage things.

As you age of course you still face unknown things, but you star to see that supposed new things rhyme with things you already know.

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

In contrast, frameworks from learning theorists such as Vygotsky, Piaget, Bloom, Gagné, Maslow, Bruner and Kolb provide more explicit actionable guidance for parents/teachers (e.g., scaffolding learning in the “zone of proximal development”, designing spiral curricula, applying experiential learning cycles).

My perspective guides me to prefer the pragmatic actionable frameworks. That help someone guiding children (or students) set norms, limits and scaffold growth in daily practice.

I do like the conversation that's cropping up here though from this article. A lot of lovely self-reflection.

> From 32 years, the brain architecture appears to stabilise compared with previous phases, corresponding with a “plateau in intelligence and personality”.

For example, here - is this *caused* by genetics, or is it because in today's society this is about the age when you have finished your schooling and first working experiences and have simply less to learn?

I know my examples simplify the reasoning, but the question about causality still stands, I think.

It was kind of odd. I'm more serious now (but at the same time.. less?). I'm way more easily able to focus on what actually matters in this life. (In saying that, I think it's more likely that my brain has finally decided what's important... in a way I feel like a passenger)

People don't grow up until they need to. Of course you're gonna see college educated rich westerners delay whatever mental markers you're looking at. And likewise people who "stay active" seem to stave off the mental decline of old age.

I am 55 but my brain tells me I am 35 or 40. This is not a "crisis of the 50s'", I did not change anything in the way I behave, it is just that I somehow stopped changing my behavior when I was around 35-40. This was not intended and it is only now that I realized it.

When I look at pictures from this time, I am very similar. I aged of course but the clothes and behavior is the same. The interests are the same. My opinions and overall maturity is the same. It does not mean that they are great, just that they do not change.

I wonder when the next change will be, when I will look at the past and say "I changed"

His answer: "I'm a better writer."

The Cambridge research cited in this study categorizes late-life changes in brain function as nothing but declining capability, all the way down. My guess is they are mostly right. But I'm intrigued by the notion that some of that elder erosion might lead to new clarity about how everything fits together.

In my late 20s/early 30s I was under water on my house, not getting paid enough, and had a small child. It was clear that I had to step up and "be a man." Which, I intuitively think had a bigger effect on me than simply getting older.

So I have, on average, another 7 years until I'm officially a typical old man? Great, just great.

But I can vouch for the earlier milestone. I grew up as a socially challenged geek with nobody to tell me that I'm just wired differently and it's not my fault, I didn't somehow not do my homework, that I'm not like the cool kids. Right around age 30 I had this epiphany... this is how I am! Instead of always looking for someone or something to teach me how I think I should be... just embrace what, in fact, I am. If I'm a geek, then just live my life best as a geek. The resulting increase in self-confidence did help socially. So just another prerogrammed "adulting" threshold? Maybe.

That is an absurdly small sample size to make such a conclusion.

It seems this age range could at least partly be culturally attributed. In modern industrialized life, many people don't have to "grow up" until a later age. At the risk of generalizing, people have more support from family, friends, and society at large.

Is the forming of those neurons based on some natural law, or is that people just haven't had to live the experiences that do so until their 30's nowadays?

As far as I know, forming neurons isn't something that "just happens". It happens due to catalysts in life. In pre-modern society, and indeed most likely in under-industrialized nations today, those catalysts, those experiences, would happen earlier. As others mentioned, there is a clear correlation with the typical age in which modern society gets married, settles down, and has kids.

I wonder what that era age would have been 200+ years ago.

Nonetheless I am never going to stop saying I still feel like I am 16. Just more confident 16.

my spouse is 3 years younger and when i told her my conclusion i added that i feel no urgency, only that something shifted

this was 3 years ago and now my spouse is 32 and said the same thing to me, someone who previously had NEVER wanted to go through the process of childbirth[0]. had to remind her that we had the same convo when i was her age

incredible that shift has been pinned down with research

[0] 10 years of big hospital nursing can be like "scared straight" for pregnancy

[0] https://andreian.com/hobbits-coming-of-age/#:~:text=What%20y...

The problem with such reports (the studies themselves method-wise etc are in general fine I guess, but how the results are interpreted and disseminated is the issue) is that unless we find some specific correlations with behavioural and such measures, it makes no sense to give these kind of meanings such as "adolescence", adult mode", behavioural/mental/cognitive matureness or whatever cultural or other norms one may think a "mature/adult person" should abide to. Especially since these abstract topological measures, while interesting, are not that trivially linked with real outcomes in a causal sense, and instead of eg simply reflecting rather environmental or other changes in a person's life.

In the last year or so I have begun to adjust my life expectations. My father was in his nineties when he died, but I no longer believe I will reach my seventies.

Things like this only tend to confirm my sense that I am neurologically ageing at a rate that is unusual.

Early 30s is mid-life mode.

Why? Because time and time again research shows we should treat people 13 and up as adults. Even when they get some extra years of youth-judgement in court, and we put 18/21 in place as lawful adult...

I just met up with my Brother-in-law and his friends for our yearly gathering. All of them are in their 30s and none of them are in what I would consider 'adult mode'.

They are all un-married/no kids, barely scraping by, partying every weekend/wasting money on weed and booze. Certainly no careers (mostly retail, some unemployed and still living with parents).

I wonder if these numbers will change with the new generation, because so many are not having kids or getting married.

That's why as you get older you start to understand what the heck is happening in your life, because you finally have multiple experiences to compare to. Then you can finally understand what is meant to be traumatic and what is right and wrong. The first time you went through something you were basically numb to the experience.

Q: "Is this based on a clearly expressed scientific theory?"

A: "Be serious -- it's just an idea, a narrative."

Q: "What would constitute a basis for either statistical validation or falsification?"

A: "You're confusing psychology with science. That's naive."