The state of your brain is moot wrt copyright as you cannot distribute your brain.
Copyright is to the exclusive right to make copies, it is the exclusive right of distributing them.
As a simple example reading a book aloud in your home or singing in the shower is not copyright infringement; not even if you record it.
If you sell tickets to these performances or stream them on twitch it becomes copyright infringing.
Similarly it cannot be in violation of copyright for GitHub to train copilot on any random code they can legally access. It can be in violation to sell access to the model trained in this way.
Copyright is to the exclusive right to make copies, it is the exclusive right of distributing them.
As a simple example reading a book aloud in your home or singing in the shower is not copyright infringement; not even if you record it.
If you sell tickets to these performances or stream them on twitch it becomes copyright infringing.
Similarly it cannot be in violation of copyright for GitHub to train copilot on any random code they can legally access. It can be in violation to sell access to the model trained in this way.