[shayan]

I wish had avoided the negative thoughts that made me depressed. I thought I was depressed because a bad thing that could destroy my dream to become a doctor had happened to me. But my depression was the result of structural damage to the brain.

The other thing is slight acceleration and deceleration of the head in every day life. A normal brain can tolerate them if they are smaller than 10G . But after a concussion, I think, the ability of the brain to tolerate them is lessened. when I was driving I felt something because of the bumps on the road. It is not like that the 1G has no effect on the brain( in my opinion)
but the ability of the normal brain to recover from that is so good that it does not leave any effect. And the greater the acceleration is, It is harder for the brain to recover. fast roller coasters have accelerations up to 2.7G so do not try them after a concussion.

Some people thing that the only thing that cause the damage in a concussion is the impact of brain to the scull but that is not true.The acceleration can cause the veins to tear and leave bruises because the blood does not want to change It's speed but the vein is accelerating.
the same thing happens with axons which are even weaker than the veins, although they might be at the center of the brain and do not hit the scull they will tear apart( not all of them of course). because of this, water diffusion increases and scientist use the water diffusion as a marker of axonal damage.
A really good way to SEE this is to drop a watermelon on the ground you will see that its color is more red which is because of the fact that water comes out of it's cells.
with all this you might be disappointed but don't be. because the ability of the brain to recover is great. just as the brain can learn a new language it can also learn how to remember things better or hear voices without hearing the ringing.
by the way the solution for avoiding road bumps is to lean a little forward. this was given by someone else.