what could a human do if they've accessed 100% of their brain?

they would just be very smart

As many users have written - we use 100% of our brain.

The brain is a very expensive organ to maintain, metabolism-wise. A large amount of calories we consume go towards powering our brain. Evolution tends to favor energy efficient forms, and there is no reason to evolve an expensive organ where you don't utilize it to the full.

Human beings already use 100 percent of their brains. LMBO we're not in a science fiction movie.

Everybody uses all the brain, as evidenced by a huge amount of neurological research.

It is (1) a myth that humans only use 10% (or some other %age) of their brain and (2) a myth that this myth is attributable to Einstein.

Even when people are asleep research has shown their brains are still very active.

Anyone with a significant brain injury has some disability as a result, even if the disability could be classed as minor. However, if we only used 10% of our brains we would not see this phenomenon. Statisitcally, the majority of people who suffered brain injuries would have the disused 90% of their brain affected and thus have no disability.

We all use all of our brains. How intelligent we all are is an entirely separate question.

"has anyone ever accessed 100% of their brain?"

Nearly everyone on earth uses 100% of their brain.

Nearly none of Yahoo Answers users, however.

This has nothing to do with Personal Finance.

Watch the movie "Lucy" for one opinion. 

Idk but my area got about 4 inches of rain on january 12, 2021

It was the most we got in over 7 years