La Trobe University concussion expert Dr Alan Pearce studied 25 former NRL players and compared them with 25 men of a similar age with no history of concussion and brain injury.
Age between 40 and 65, the men all completed five tasks relating to memory, short-term learning and attention, reaction time and fine motor skills.
Dr Pearce used Transcranial Magnetic Stimulation (TMS) to deliver electromagnetic pulses to parts of participants’ brains to measure changes in their brain activity.
The research found the brain function of the former rugby players was worse than that of the control group.
“For the first time we have clear evidence that repeated head knocks in rugby league can have a devastating impact many years after the concussion occurs,” Dr Pearce said.
“The results show a significant difference in the brain function of the NRL group compared with other men their age who had never suffered a concussion.
“The former players performed 40 to 50 per cent worse on cognitive testing. They were also 14 per cent slower in the dexterity test and 11 per cent slower in their reaction time.”
The retired NRL players who took part in the study reported having an average of eight concussions during their careers, with the last of these occurring an average of 18 years ago.
In 2014, Dr Pearce conducted a similar study that included 20 retired AFL players and 20 amateur footballers who had suffered repeated concussions. He found both the elite and amateur players performed markedly worse in fine movement control and reaction times compared with a group of men who had never played a contact sport.
“The significance of that study was the finding that the level of sport played did not influence the long-term outcomes of repeated concussions.
“The NRL study takes concussion research to a new level by looking at the long-term impact of repeated concussions.
“The findings raise serious questions about whether as a society we are properly dealing with the issue of concussion in contact sports.”
Dr Pearce hopes his landmark research is the first step in determining the long-term impact of impairment resulting from repeated concussions and will lead to further research toward rehabilitation to maintain a healthy brain, not just for athletes, for everyone in the community.
His research has been published in Brain Injury.
The tests carried out on the 50 study participants were as follows:
- Reaction time – quickly touching a target when it appeared on a tablet screen
- Memory – repeatedly finding and remembering tokens located behind boxes
- Short-term learning – identifying the location of discrete patterns concealed behind boxes on a screen
- Short-term attention – concentrating on one figure on a screen as two figures are randomly displayed on a screen
- Fine motor skills – picking up, manipulating and placing three small pins into different holes
(Source: La Trobe University)