Concussions are tricky injuries. You can't always diagnose them right away, and multiple instances can compound on each other, resulting in some very nasty brain trauma over time.

NFL players are no strangers to concussions, and the debate is heating up over how to minimize head injuries on the field. Reebok and mc10 seem to be taking a step in the right direction with their new gadget CheckLight. Reebok came up with a tight-fitting headcap, while mc10 built the sensor that goes inside, alerting medical technicians on the sidelines whether the athlete is concussed. It provides a more accurate read-out than previous sensors, which only measure the impact to the helmet, not the athlete's head. 

The plastic strip sensor monitors rotational acceleration, multi-directional acceleration, impact location and impact duration, runs that information through an algorithm, then uses an LED light to indicate whether the impact eas severe enough to cause a concussion. Reebok plans to release the cap for younger athletes as well, not just professionals.