England’s 37-year-old former Canterbury and St George Illawarra forward, who says he endured more than 100 concussions and 18,000 collisions during his career, has undergone a series of tests since his retirement.

He says he had performed well on a neuro-psychological exam, but a new MRI scan has been less positive.

“The MRI scan of the brain shows some dark spots on there, which are of concern to my doctor and my neurologist,” he said.

“And then also there’s an area of the brain that the volume is in the bottom three percentile of where it should be, which they believe is likely linked to repetitive head trauma.”

The news comes after a law firm confirmed it would send a letter of claim to the Rugby Football League on behalf of a group of former professional and semi-pro players, alleging the governing body failed to take reasonable action to protect players from permanent brain injury.

The group includes former pros Francis Maloney and Bobbie Goulding who have been diagnosed with early-onset dementia.

Graham, who’s not part of the group, has previously stated his intention to donate his brain for scientific research when he dies.

He said he had not been given a definitive diagnosis based on the MRI scan, and that he will be subjected to regular monitoring.

“People ask, ‘are you nervous, are you worried?’ No. I’d rather know. I don’t want to plead ignorance throughout this whole process. I’m not naive enough to think that the game that I played, in the way I played it, I’m not going to pay a price for that,” he added.

“So actually, for me to have this knowledge it gives me greater motivation in order to keep up with some of the changes that I’ve made in my life. I try and stack the odds in my favour for better future health outcomes.”

Graham has long campaigned to make his sport safer.

“It’s clear we have to act,” Graham said.

“There are a number of recommendations out there in order to try and reduce that risk (of developing neurodegenerative disease). I don’t think you’ll ever be able to reduce that down to the national average.

“However, I will say this about the benefit of sport – the evidence on that is crystal-clear, not only for the individual, but the community and society in general as a whole. So, make no mistake, sport is good, but it needs to be safer.

“I don’t have any regrets about the way I played. I was a product of my environment. It used to be worn as a badge of honour to be concussed or knocked out and get up and carry on.

“It was seen as courageous, brave, tough, all the attributes of the warrior-style mentality, continuing on and not wanting to leave the field under any circumstances. I think there needs to be a culture shift and environmental shift.”