Sam Harnett reports on efforts by Stanford researchers to “see brain trauma in real time”:

[David] Camarillo and his team have outfitted the football team with mouth guards that measure the physics of every hit. At practices, they use ultra-high-definition, slow-motion cameras to observe those collisions more closely and look for ways to prevent them. The first startling discovery of the research is how little is known about the “injury mechanism” for concussions, that is, exactly how they are caused… How hard does a hit need to be to cause a concussion outright? How many small, low-impact hits before a player begins to exhibit concussion symptoms?

Some of the findings are downright scary:

Camarillo says the mouth guards have already captured some startlingly hard hits, like the one that ended the season for a wide receiver. That collision registered an acceleration of 150 Gs, that’s 150 times the acceleration gravity. “Pretty serious business,” he says, “a standard boxing punch is probably between 10-20 Gs.”

That’s just acceleration in one direction. The player’s head was also spinning at 2000 degrees per second—which means his head would have rotated five and a half times in one second if it weren’t anchored to the neck.

While it has long been suspected that this kind of angular acceleration plays a role in concussions, Camarillo says no one has gathered data on it. What’s more disturbing is that angular acceleration has been completely ignored when it comes to football safety measures.

The entire Dish thread on concussions in football here.