Hi Quarky,
What about every kid before they learn a language?
We are not born knowing a language, but with the ability to learn or create a language.
Before you have a language, the only thing you have are your senses.
Thought, in the sense of the mental manipulation of concepts (words) is impossible without language (words). Try to think of something you can "think" about without naming it.
Again this does not mean nothing is going on.
Being in direct contact with your senses (without the constant commenting on them by thinking about them, or being distracted from them by thinking about something else) would probably be pretty close to feeling that " all the (your) neurons (are) firing simultaneously".
All of your senses work by themselves pretty much 24-7, and you are able to experience this somehow in your mind, without the interference of thought.
Consider the child, when it is not uncomforable (wet, tired, hungry) it is pretty much having a ball, enjoying the piss out of life.
Of course most of his/her enjoyment of life will start coming to a screaching halt once we teach it a language and tell it to be reasonable, and try to answer all of his/her questions logically.
Thanks
Chunol