Concussion study finds brain networks affected by head knocks

Florey researchers have imaged the brains of concussed AFL players to uncover signature changes that occur after a head knock.

The world-first study, led by the Florey’s Professor Graeme Jackson, used advanced brain imaging to uncover common changes in functional brain connections in the month after a concussive head knock in AFL players.

Structural brain imaging following a concussion shows no damage that explains the common symptoms, and concussion management usually only assesses general or self-reported symptoms, for example by using the SCAT5 concussion test [PDF].

Using functional MRI — a type of brain scan that looks at blood flow in the brain after neurons have been firing — first author Dr Mangor Pedersen said while there was no difference in the brain’s physical structure, the 20 concussed athletes all showed reduced activity in parts of the brain responsible for executive function, working memory and switching tasks.

Dr Pedersen said, “The main challenge in the field has been to find an objective marker of acute concussion to determine when players can return to play.

“Looking at how the different parts of the brain talk to each other, we can see these three brain networks are affected, and these changes may help explain the symptoms we see in concussed players.”

Professor Jackson said the study showed there was a very specific network in the brain affected during concussion.

“It almost redefines what concussion is,” Professor Jackson said.

“We used to think concussion was a diffuse head injury, but we know that’s not true.

“This paper shows there is a very well recognised network, a specialisation in the right hemisphere, that gets affected in concussion.”

Prof Jackson said they were now analysing the brain scans of individual players to uncover the unique functional changes in brain networks, with the goal of turning their findings into a tool to guide personalised treatment and recovery.

– Story adapted from the Herald Sun