A driver behind you at a red light fails to stop in time. He looks lown at his phone and does not see that traffic ahead has stopped. His Ford F-150 pickup truck plows into the back of your Prius and you wind up in the hospital with serious injuries.

Cosmetically, your injuries start healing quickly. That cut on your face scabs over and begins to fade. Another scrape running down the length of your arm, where you hit the steering column, also starts healing. Doctors tell you that, though you may have light scarring, your skin will heal and look as good as new in a matter of months.

You also suffered a brain injury, though, when your head hit the wheel. You have trouble speaking at times and also struggle to keep your balance. You feel tired and drained every day and have mood swings. These are all classic signs of a traumatic brain injury (TBI), and the doctors are not as positive about this aspect of your recovery. In fact, they tell you that your brain may never completely heal. You may have to deal with these symptoms for life.

Why is it that your skin can heal and your brain cannot?

Natural regeneration

One reason is that skin cell regeneration is natural and happens all the time. Your body is designed to replicate your skin cells even when you haven’t suffered any injuries. There is constant turnover.

When your skin gets hurt, your body is ready. It can create new cells quickly and heal broken areas. Signs of trauma fade with time, as those cells get replaced.

The brain is not wired this way. Regenerating the delicate mix of brain matter is a much rarer process. Some brain cells get used for life. You never get more. They either last until you pass away or they do not. Your body cannot create a new set.

This is why brain injuries are so traumatic. Your brain never expected those cells to die early. It has no way to replace them. When the death of specific cells leads to disabilities and serious cognitive issues, your body cannot always repair itself.

Why is this?

Some have argued that this is clearly a disadvantage for humans as a species. Why wouldn’t the body have a way to recreate brain cells and recover from serious injuries when it’s so easy to recover from what we now consider minor injuries?

Part of the reason, scientists believe, is that the brain is well protected. Your skin stays exposed all the time and suffers numerous injuries. Your brain remains shielded with bone, where it should never suffer a serious injury. In that sense, the problem is that modern cars are simply more dangerous than the human body can handle, with their weight and the high-speed accidents they cause.

No recovery

Not having any ability to recover means brain injury can last for life. Those who suffer them need to know all of their rights.