Former NHL forward Daniel Carcillo pledged to donate his brain to the Carrick Institute for research into the effects of traumatic brain injuries. The longtime enforcer who played three seasons with the Blackhawks announced his decision Wednesday night as part of his reaction on social media to a series of illegal hits during the Stanley Cup Playoffs.

Carcillo retired from the NHL in 2015 and has since devoted his time to advocating research into mental health and the effects of concussions. The 33-year-old started the Chapter 5 Foundation in honor of Steve Montador, a best friend and former NHL enforcer who died at age 35. He has been vocal on social media about the need for the league to better handle the risks and long-term effects of playing hockey.

One change Carcillo specifically called for Wednesday was the outright banning of hits to the head at the NHL level. The IIHF, NCAA and OHL have adopted those rules, and back in 2011, some big-name players said they were in favor of following that trend. However, the league has been slow to change, instead adopting half-measures meant to discourage and penalize certain head hits without banning all of them.

In March, Carcillo joined the concussion lawsuit against the NHL that was filed four years ago by a group of former players. A judge in Minnesota is currently reviewing whether the case should go forward as a class action lawsuit, which would automatically make roughly 5,000 former players plaintiffs and turn up the stakes for the league.

“I’m not a bitter guy looking to hurt the NHL,” Carcillo said at the time. “I’m not out for money. I’ll donate anything I get to research. I just want to put pressure on the NHL and educate and advocate for guys.”

Carcillo played 429 NHL games over nine seasons with the Coyotes, Flyers, Blackhawks, Kings and Rangers. He won a Stanley Cup with the Hawks in 2013, but said Wednesday that he “would trade my name on the [Stanley Cup] twice over for another conversation with Steve Montador. That’s how much I care about this advocacy work.”