Thoughts are half formed, started partway through and never finished. There is the half flickering images of the day that was. The jerking awake of the to do list for tomorrow.
Sometimes, if you are lucky there will be drips and drabs of words and sentences passing through the brain on a gentle wind.
Stories and words and ideas that your mind is conjuring up in the subconscious of sleep.
Your job, the next day, is to remember them, to capture the mood of the darkened hours on the computer screen. Put in the full stops and capital letters.
Rework the ideas to make them readable, to find out what your brain was really thinking when your body wanted to sleep.