Let me tell you something about the human brain that may just astound you.
Well, my brain anyway.
There are times in my life when I am only using 10% of my brain.
I am only using 10% of my brain...
...when I am only including 10% of what my brain does.
The other 90% of my brain is doing the other 90% of what it does. At the same time!
None of my brain is particularly numbed or lying fallow. It’s all kinda doing the thing it does.
So, if we could dispense with the whole “We only use 10% of our brain” fairytale, that would be awesome.
There are a lot of great premises about how people can be smarter or more magical than others, and they all make more sense than “most people only use 10% of their brains.”
Midichlorians, for example, are far more probable than the notion that our brain basically lies as disused as gum on a taxicab floor. If midichlorians are more realistic than your premise, you need a new premise.
Or a new brain.