The Professional Footballers' Association (PFA) has been "hurt" by criticism of its dementia record but has vowed to change and improve.
The players' union has come under fire from the families of former England internationals Nobby Stiles and Jeff Astle, both of whom had dementia before they died.
They believe there has been a lack of support for families of former players and for research.
But after the PFA set up a brain injury disease taskforce, assistant chief executive Simon Barker told BBC Sport: "There has been a lot done in this area.
"I've spoken to Dawn [Astle's daughter] and my colleagues have spoken to John [Stiles' son] and we need to take on board any criticism, we can’t ignore it. We need to adapt and change and improve.
"When I hear of that criticism, it hurts me and my colleagues because I know how much we care.
"If we are not doing what our members want us to do or not going to level they think we should, we should listen to them and improve as much as we can."
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On Wednesday, John Stiles responded to Barker's comments by calling for the PFA "chief executive and his leadership team to resign".
He also said that although the PFA had offered "some very limited support" over the last three years, the union had not been in touch with the family since his father died.
"I have no confidence that the PFA leadership team can address the scandal," he added in a statement.
"The review process, begun through the diligence and persistence of Ben Purkiss, needs to be completed as a matter of urgency."
The PFA announced its Neurodegenerative Disease Working Group (NDWG) last week, which would seek to consult the likes of Astle and former Blackburn Rovers forward Chris Sutton, who has also been critical of the union after his father, a former footballer, was diagnosed with dementia.
Sutton has told BBC Sport he has "no plan to join the taskforce and doesn't want to be associated with the PFA in its current guise".
The PFA also said it would continue to fund Dr Willie Stewart's research into the issue after the neuropathologist found last year that former footballers were between two and five times more likely to die from degenerative brain diseases.
And on Friday it called for heading in training to be reduced in order to protect current players while a potential link between heading and long-term brain injuries exists.
Stewart found that Astle died in 2002, aged 59, of a brain condition normally linked to boxers, and that it was caused by heading footballs.
Stiles, who passed away last month, aged 78, is one of five members of England's World Cup-winning squad to have been diagnosed with dementia.
His family told the BBC last week that football needs to "address the scandal" of dementia in football.
But Barker, a former midfielder at Blackburn Rovers and Queens Park Rangers, defended the union’s record on helping former players and funding research.
He said: "We might be talking in the hundreds [of families] that we have dealt with, but we only know of the ones who have come to us. We want to help former players and their families. We want to help current and future players as well.
"We have never turned down any family in terms of support, and definitely not in respects of research, only where it conflicted with other research programmes that were already funded."
Barker said there were "five or six" further research projects ongoing, with the PFA supporting three of them.
'We can start reducing heading now'
Barker also said the union would continue to lobby clubs and leagues on reducing heading in training and the use of concussion substitutes.
Football’s law makers Ifab are set to allow leagues to use concussion substitute trials from January 2021, with the Football Association aiming to introduce them from the FA Cup third rounds in both men's and women's football.
Barker added: "Although there isn't causal link based on the research, we believe the game needs to work on the assumption that heading is a contributing factor until proven otherwise.
"We can start [reducing heading in training] now, there are no laws in respect of training. I've seen managers say they don't do that much, but what we would like to see is something across the board."
Like Dr Stewart and world players’ union FifPro, the PFA wants temporary substitutions rather than permanent ones proposed by Fifa and Ifab.
"Hopefully it will be adopted by all leagues to start trials," Barker said.
"We will be lobbying for it without a doubt with leagues and the FA, and hopefully it comes into the laws of the game.
"We wanted temporary substitutions, and from what I hear it might be permanent, but whichever way, it’s got to be about player welfare."