Sounds like something is missing.
The only thing for sure is that the brain is one of the last organs humans know comparatively little about, except for having mapped the regions and general areas that control certain functions on each side of the brain. Here’s a few things that have been proven:
The average person uses 2-3% of one’s brain capacity; geniuses like Einstein are credited with 6% use.
The brain is incredibly adaptive, with known cases of a man ca. 1920 who suffered a tragic accident as a construction worker, where a small steel pipe was rammed from the bottom of his lower jaw upward diagonally to the right, THROUGH his brain. Because he knew 3 languages (this was credited in part for his amazing recovery) and despite the primitive brain surgery techniques of the time, he was able to relearn all the basic functions (walking, talking, tying his shoes, dressing himself, eating, going to the restroom) + even resume working albeit at a diminished capacity. There have been other general cases where people suffering from frequent and heavy seizures had one entire portion on one SIDE of the brain removed to not only stop the seizures but to also improve their standard of life experience.
To dovetail off of #2, the brain STILL forms new connections and creates new neurons even past the generally accepted ages of 4-9, when the brain’s connections are created at the fastest rate. It is NOT true that “you can’t teach old dogs new tricks,” as even older people (barring organic defects like Alzheimer’s) have still been able to learn completely new skills like languages and jobs–and even recover from fairly serious accidents like concussions and attacks like strokes.
The only thing that is certain otherwise is that men cannot explain exactly why the brain adapts and overcomes certain adverse occurrences whereas in other cases it should do the same but does not. It is still largely a mystery to man, and will likely stay that way.