Bianchi's brain injury explained

Following a horrific crash in last weekend’s Japanese Grand Prix, Jules Bianchi was diagnosed with a diffuse axonal injury (DAI) reported the Independent. DAI is a severe brain injury that is a relatively common outcome of high-speed crashes.

Axons are the long part of neurons which connect to other neurons, essentially allowing the neuron to do its job of communicating with other neurons. If an axon is damaged or destroyed, the neuron can no longer communicate and whatever function it was responsible for is lost.

There are up to 100 billion neurons in the human brain, so the loss of a few neurons, even a couple of hundred, is unlikely to notable impair the functioning of the individual. However, in the case of DAI the number of neurons destroyed can be much, much higher, leading to a range of serious health consequences, including death.

Bianchi’s injury occurred when his Marussia F1 car sped off the track and collided with the recovery vehicle. This resulted in a rapid deceleration of his body with the momentum crushing his brain against his skull, thus destroying the neurons.

Read: Car crash, what now?

DAI is also unlike other brain injuries in that the damage is not localised to one specific area. In many brain injuries the damage is limited to a specific region and thus only the functionality provided by this region is affected. This is why individuals with localised brain injuries may lost the ability to smell, for example, but still lead relatively normal lives.

In a DAI, functionality across the brain may be impaired beyond the point that the brain can make up for. This is compounded by the fact that neurons in the brain cannot, as a rule, repair themselves when damaged. This usually means that whatever damage has occurred is permanent.

Due to the massive neural trauma suffered, most victims of DAI never wake up, according to Brainandspinalcord.org. Depending on the affected areas, their body may continue to function, essentially leaving them brain-dead. Alternatively, if the damage is too severe the body may not be able to sustain itself, leading to death.

Currently, the extent of Bianchi’s injury, and thus his prognosis, is unclear. His family can, however, take heart from another driver, Michael Schumacher who suffered similar injuries following his skiing accident but will soon be able to lead a “relatively normal life,” as reported by the Mirror. Schumacher was in a coma for six months.

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F1 injuries not under control 

Image credit: Brain injury from Shutterstock