Football player-turned-murderer Aaron Hernandez had what doctors called the most severe case of CTE ever discovered in a person his age.

At a press conference Thursday in Boston, researchers revealed that damage from Hernandez’s CTE, or chronic traumatic encephalopathy, would have significantly affected his memory, impulse control and behavior.

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Breaking Celebrity News readers will remember the former New England Patriots tight end committed suicide in April in a Massachusetts prison while serving a life sentence for the murder of his friend Odin Lloyd in 2013.

Dr. Ann McKee, the head of Boston University’s CTE Center, says Hernandez had Stage 3 CTE, which researchers had never seen in a brain younger than 46-years-old. And while they couldn’t exactly blame the CTE for Hernandez’s violence, it could have been a contributing factor.

“We can’t take the pathology and explain the behavior,” McKee said. “But we can say collectively, in our collective experience, that individuals with CTE, and CTE of this severity, have difficulty with impulse control, decision-making, inhibition of impulses for aggression, emotional volatility, rage behaviors. We know that collectively.”