critical but others in the field contend that far more study is neededthe problem is that these findings are being put out there too fast and stated too strongly by one group before we understand who gets cte how it evolves over time whats the risk any of that said dr lilinaz hazrati a brain pathologist at the university of toronto who said she had received no financial support from either the nfl or the players associationmembers of the boston lab say they have raised the alarm for a good reason the risk is real but agree that the cte story is far from complete this research is in its infancy said robert stern a professor of neurology and neurosurgery at the boston university school of medicine who works with dr mckee there are many outstanding questions but were now working to answer them and making some progress the national institutes of health has committed some 20 million to research and the nfl more than 70 millionthe group has made its diagnoses of cte with authority often stating them in terms of stages similar to a cancer diagnosis dr mckee has determined four pathological stages which she has linked to psychological problems like depression or explosive anger she said the stages themselves are clearly distinguishable on postmortem slides of brain tissues but she acknowledged that their proposed link to specific symptoms is totally preliminary it probably wont hold up we dont know yet how the pathology stages predict behaviorpart of the challenge in answering these questions is that doctors can only diagnose cte after death by dissecting a brain that process allows them to identify a subtle pattern of a brain protein called tau clumped in critical areasit was only last year that a panel of experts convened by the federally funded national institute of neurological disorders and stroke agreed that this tau pattern was definitively distinct from patterns of tau that signal other conditions like alzheimers disease or agerelated declinethat was a first step nothing more said dr walter koroshetz the institutes director we had to establish minimal criteria so that all researchers were using the same standards the agency is now funding research into detecting cte in living people and clarifying the link between its stages and symptomsthe medical literature generally describes cte as closely related to punchdrunk syndrome or dementia pugilistica the stiffness tremors and early dementia first found in some professional boxers a halfcentury ago but when dr bennet omalu a pathologist in pittsburgh reported the telltale pathology in a deceased football player in 2005 which became the basis for the 2015 movie concussion the research took a different turn team contact sports produce different kinds of blows to the head than boxing and research into those athletes accelerateddr mckee and dr stern had studied alzheimers disease for decades after dr omalus report dr stern was giving a lecture about dementia when he met chris nowinski a former wrestler and football player who spoke to him