Howard Fendrich, AP

The National Football League is partnering with Boston University brain researchers who have been critical of the league's stance on concussion. The league now plans to encourage current and former NFL players to donate their brains to the Boston University Center for the Study of Traumatic Encephalopathy, which has said it found links between repeated head trauma and brain damage in boxers, football players and, most recently, a former NHL player.

“It's huge that the NFL actively gets behind this research,” said Robert Cantu, a co-director of the BU center who has spoken negatively about the league in the past. “It forwards the research. It allows players to realize the NFL is concerned about the possibility that they could have this problem, and that the NFL is doing everything it can to find out about the risks and the preventive strategies that can be implemented.”

NFL spokesman Greg Aiello told the AP on Sunday that the league is also committed to giving $1 million or more to the center.

The BU group and the NFL Players Association jointly announced that the union will also work with the center and encourage players to participate in the studies. The league is contacting nearly 100 retired football players who have been diagnosed with Alzheimer's or dementia to ask their families to consider donating those players' brains to the BU study.

This news represents the latest in a series of moves the NFL has made in recent weeks to step up its attention to concussions in the aftermath of a congressional hearing on the topic, and as high-profile players such as Ben Roethlisberger, Kurt Warner, Clinton Portis and Brian Westbrook have been sidelined by head injuries this season.

The league's steps included stricter return-to-play guidelines detailing what symptoms preclude someone from participating in games or practices; a mandate that each team select a league and union-approved independent neurologist to be consulted when players get concussions; and the departure of the two co-chairmen of the NFL's committee on brain trauma.

“They have done a bit of an about-face. Pressure probably has played a role in that,” Cantu said in a telephone interview. “But I honestly think that (Commissioner Roger) Goodell does believe in player safety and the product is just better with your best players on the field, not your best players injured.”

Aiello said Sunday that a concussion study the league has been conducting since 2007 is on hold until the former committee co-chairmen are replaced after resigning last month. He said the league is interviewing candidates, none of whom is currently affiliated with the league or any team.