There's been this trend going around on TikTok that sees grown men and women filming themselves hitting up their local toy aisles and picking out new Barbie dolls for themselves ... all for the sake of fulfilling their inner child and achieving emotional support.

It's a whole thing now, apparently ... in the wake of the movie coming out this summer, some people are buying themselves the dolls they never had -- that or gifting them to loved ones (like parents) who might've not had such toys growing up as kids.

A psychology professor, Kristin Flora, tells CNN this is a good thing ... as grown folks now feel comfortable not only reconnecting to their childhood -- but also sharing that, and it seems to be well-received on social media. Obviously, this lends itself to mental health, etc.

It's just further proof that the "Barbie" flick has truly impacted American culture this year ... and, regardless of the reason, it continues to positively affect bottom lines as well.

We already know it's made Warner Bros. a billion-plus dollars and with this apparent boom in doll purchases to boot ... Mattel's also probably smiling all the way to the bank. Plus, this seems to really make people happy in general.