Question

why we can use only 10 percent of our brain

Answer 1

When someone says you are only using 10 percent of your brain, what does that mean? And how do we know that we only use 10 percent? We would have to know what 100-percent capacity looks like before we could say we presently use one-tenth of it, right? Here is the science behind it all. 

Have you ever met anyone who is missing 90 percent of their brain? Probably not. You have never heard of anyone with that much brain missing, because pretty much all areas of the brain are capable of electrical and chemical activity. People wouldn’t be able to function with that tidbit of grey matter. Even the regions of the cortex in blind people that normally process vision are co-opted for other functions. Everyone makes use of the entire brain.