Ormsby made 89 appearances for Rovers after joining the club from Leeds United in 1990.
The 61-year-old suffered a stroke in 2013 which left him unable to speak and a neurologist has told his family he is living with CTE – a neurodegenerative disease linked to repeated blows to the head.
Brendon’s wife Wendy, who cares for her husband full-time, believes his condition has been caused by heading the ball.
A Leeds United Legends Night was held at Elland Road earlier this month to raise money for Brendon.
Former Doncaster Rovers midfielder John Stiles, son of 1966 England World Cup winner Nobby, helped organise the event.
Stiles lost his father to dementia in 2020 and is an active campaigner in raising awareness of the dangers of heading the ball.
"It's not just the sufferer,” Stiles told the Daily Mail. “It's the people around them. It's the entire family, and we want to help the Ormsby's.
"Brendon was a wonderful lad and a great player who put his heart and soul into football.”
A recent study in Norway claimed that heading the ball ‘changes blood patterns in the brain’ which could potentially cause damage.
Birmingham-born Ormsby spent eight years at Aston Villa before captaining Leeds to the FA Cup semi-finals and Division Two play-offs in 1987.
He left Rovers to join Scarborough in 1992 before retiring from football and working as a postman and football data reporter for the Press Association.