The human brain is not a single organ, but two separate systems that evolved independently before fusing together, according to groundbreaking new research. … Armed with the knowledge of how hindbrain cells uniquely form, the team has successfully turned human stem cells into becoming functional hindbrain motor neurons in a lab for the first time.



I’m more surprised that it’s separated as front and back, and not right to left.
The left/right brain thing has always been bunk. People have entire hemispheres removed with minimal negative consequences, personality changes, etc.
The personality test stuff is bunk. Pretty sure the experiment with the one hand drawing something and the other hand doesn’t know are real.
Are you sure people can have an entire hemisphere removed with minimal consequences? That sounds absolutely wild!
There are brain surgeries where you just chuck out the extra to get to the parts you want to work on, eloquent vs non-eloquent tissue. And epilepsy surgery where they completely disconnect the halves. Recently read a pretty good book on this.
If you skip the first chapter, and then stop once he starts talking about anything other than neuroscience The Immortal Mind is a great overview of this by an extremely talented neurosurgeon who has dog shit views on literally everything else. Still worth it for the good parts but I warned you.
I learned this a while ago so I had to double check!
https://en.wikipedia.org/wiki/Hemispherectomy
so. here is the thing. that. to me. is more of an indication the two hemispheres are independent and thus the left right thing. If we take the previous paragrpah into consideration:
We can see that indeed the other hemisphere has to expand its capability from what it had pre surgery and that much of what they are looking at is basic function and not like if they were as good at art or reasoning after surgery.