Kathryn Paige Harden

Generally speaking, in the U.S., people are

behaving in much more controlled, less disinhibited ways across the board.

And we can see that even at the extremes.

They're not really the same thing.

Are they acting more responsibly?

I think responsible is a harder concept to define scientifically.

They're certainly engaging in less risk-taking.

Now,

it might be that they're engaging in less risk-taking.

And this is one theory.

It hasn't been.

This isn't dispositive.

But one hypothesis is that they're engaging in less risk-taking because they're also just around people less and spending a lot more time at home with their phones.

And that might be good from the perspective of risk-taking and antisocial behavior, but not great from the perspective of mental health more broadly if you've just substituted risk-taking for social isolation.

So

How we understand these broad historical trends is difficult.

What's interesting to me about that from a perspective as a behavioral geneticist is that Americans' genes haven't changed in the last 30 years.

That's not nearly enough time for us to have evolved differently in that period of time.

So it's another piece of evidence that even though there is a genetic component to risk-taking, to antisocial behavior, to aggression, to violence, that genetic component is not deterministic because we are seeing it change even in this short period of time.

It seems to be also really responding to the social environment that a child is developing in.