how do you know the brain is repairing from injury?

[yamiyills]

what are the activities that take place in the brain during this period of repair

[JAR]

The major clue I know of is hearing a clicking sound.
If the skull was broken during the injury then you will hear a clicking sound as the bone mends. It's annoying as anything you've ever encountered, but do NOT press where you're hearing or feeling the clicking. Trust me on that - it can become a nightmare.
Expect one year of recovery - dizzy spells, horrible ones when you lean over. Don't lean over - that puts more stress on the brain and oxygen flow. Bad results if you aren't careful.
The synapsis have to re-learn a route. So to speak. Because of the damage tissue, the signals have to go from point A to point B in a different route. That learning takes months. Any mis-firing of the synapsis will cause convulsions.

Are you asking from the learning side or the patient side?