There's definitely some interesting physics there, but as far as i know, no one has figured it out satisfactorily. One of the most popular animal models of traumatic brain injury (it's also in fashion these days to refer to concussion as a mild TBI) is call the "lateral fluid percussion" model. In this model, you open up the animal's skull and use a tube to direct a compression wave of about a couple atmospheres (I think...can't remember the exact number off the top of my head) to the direct top of the brain. The injury it creates is a very focal lesion far from the site of the blast, but always in the same spot (lateral to the blast, hence the name). I suppose that suggests that it creates a travelling wave that bounces around the brain and two or more of the rebounds create a superposition at the site of the lesion, but I'm not really sure about that.

Is that similar to, different from, or complimentary of the diagrams and videos that show the cause of a concussion of the brain just bouncing back and forth in the skull?