When people think of concussions in sports, they visualize a football player flying headlong into a tackle and the crack of helmet-on-helmet contact.  And while a direct hit to the head is certainly a possible cause of concussions, it is by no means the only culprit.

Let’s start by laying out what is going on in your head during a concussion.  The brain is soft and surrounded by clear cerebrospinal fluid.  This fluid, amongst other things, serves as a buffer between your brain and your skull.  Normally, it absorbs the shock of a blow to the head and keeps the brain from being buffeted against the skull.  During a concussion, however, your head receives a shock, such that your brain hits the hard skull bone and begins to swell from the impact.

1. Direct Head Trauma

This one seems obvious:  it’s what most people think of when they hear the word concussion.  A direct hit to the head, especially one that snaps your head backwards is very likely to cause a concussion.

2. Whiplash

There is a direct link between neck strain injuries like whiplash and concussions.  Whether this is from a car accident or a huge hit in football, many cases of whiplash or a similar neck injury coincide with a concussion.

3. Falling

Anytime you take a jarring fall, you are put at risk of a concussion.  Similar to whiplash, it may not be a direct hit to your head, but an overall jolt to your body that can cause a concussion.  Falling is one of the most prevalent causes of concussions that are not sports-related.

4. Explosions

Common mainly in people serving in the military, concussions caused by explosions are actually quite unique.  Rather than a physical trauma causing the brain to hit against the skull, these concussions are caused by the nearly instantaneous changes in air pressure that occur during an explosion.  And according to a recent study published in the Journal of Neurotrauma, concussions caused by explosions could contribute to PTSD.

5. Spinning Your Head

Rotational force can actually be more damaging to your brain that direct force.  So whipping your head around too quickly, especially when stopped suddenly, is a good way to give yourself a concussion.  If you feel suddenly foggy and lightheaded after such a spin, it may be the early signs of a concussion.

6. Lesser Injuries

Sustaining several mild brain injuries that don’t qualify as a concussion can, over time, build up into the equivalent of a concussion.  In fact, in some cases these sub-concussive level injuries result in more damage because they are never diagnosed and treated.

7. Previous Concussions

Your chances of concussion increase exponentially after every concussion.  So after one concussion, you are 2-4 times more likely to get your second.  After the second concussion, you are 4-6 times as likely to get a third.  From there, you are 6-9 times more likely to get a fourth.  And so on.  That is partly due to the fact that people who suffer multiple concussions are usually involved in activities in which concussions are more prevalent. But it also has to do with the chemistry in your brain.  The chemistry is changed during a concussion, and that change can leave you vulnerable to having a second concussion.

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