The brains of at least three former Seattle Seahawks are being analyzed as a part of a Boston University study into NFL players’ head injuries. The brains of center Grant Feasel, defensive back Doug Long, and defensive end Cortez Kennedy have been donated to science in the furtherance of research.

Boston neuropathologist, Dr. Ann C. McKee, is leading the investigation into the possible causes of chronic traumatic encephalopathy, referred to as CTE.

In the initial results of her study released last year, McKee revealed 110 of 111 brains examined from deceased NFL players showed signs of CTE. The brains of Feasel and Long were analyzed at that time.

“Every time you see anything brown, it’s abnormal,” Dr. McKee told KING 5, referring to a slide of Feasel’s brain. “All this brown is Tau protein inside of nerve cells, and that’s what the Tau does, it builds up inside of nerve cells and leads to loss of cognitive skills, depression and suicide.”

At this time, the CTE diagnosis can only be made post-mortem, but that isn’t stopping retired players from donating their brains to future studies.

According to the KING 5 report, former quarterback Matt Hasselbeck, linebacker Isaiah Kacyvenski, guard Pete Kendall, defensive back Shawn Springs and linebacker Lofa Tatupu have all pledged their brains to the Boston University program.

“I thought, ‘They’re going to need brains that are asymptomatic,’ people who played for a long period of time and don’t feel like they have any issues,” Hasselbeck told KING.

The hope is for an eventual early diagnosis and course of treatment for those suffering from CTE.

“The end goal has always been to help future generations, future athletes, future military veterans,” Dr. McKee said. “We really want to be able to treat the disease.”