Will Smith knows about it. My mom knows about it. You probably know about it, too. Chronic Traumatic Encephalopathy (CTE) has gotten a lot of attention in recent years, mostly thanks to the NFL. Commonly associated with repetitive head trauma, CTE is a neurodegenerative (i.e. brain cell destroying) disease that affects the sufferer’s cognitive and emotional faculties, in some cases invoking suicidal thoughts and behavior. As the trendy new neurodegenerative disease, researchers have been clamoring to find out the real cause of the illness in the past decade. Since it was brought into the limelight in 2005, and since its discovery in 1928, CTE has been most strongly associated with head injury. A few days ago, however, it became public that researchers at Toronto Western Hospital found CTE in a deceased patient with absolutely no history of head trauma.

To be more specific, not only did the patient have no history of head trauma, but he/she also did not exhibit any of the symptoms associated with CTE. Despite all this, the neural changes specific to CTE were still found in the posthumous brain.

Previously, we were all under the impression that the changes to the brain that happen at the cellular level classified as CTE were due to physical injury to the cells from an impact to the head. What’s confusing is that that one constant factor is completely absent. Even more confusing is the fact that while CTE is associated with head trauma, you don’t need a history of concussions to present with CTE, some people bang their heads against anything solid and still don’t develop CTE, some develop it later in life, while still others end up dying of effects of CTE in high school. We already knew CTE could affect a wide range of people very differently according to their history and possibly their genes, but how this can extend to someone who had no symptoms or apparent cause is unsettling.

Basically, all this means that we know a lot less about CTE than what we thought. The hope is that continuing research involving postmortem donated brains will continue to yield greater insight, but the more troubling question is whether or not we're looking for answers in the right places.