How to explain your concussion to others with SCIENCE

DISCLAIMER: I am not a doctor nor do I intend to play one on the internet.

When attempting to answer the concussion, “what is a concussion?” the answers are many and high variable.

Here are some definitions from respected sources:

CDC:

“A concussion is a type of traumatic brain injury—or TBI—caused by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth”1

Mayo Clinic:

“A concussion is a traumatic brain injury that affects your brain function. Effects are usually temporary but can include headaches and problems with concentration, memory, balance and coordination.”2

WebMD:

“A concussion is a type of traumatic brain injury that is caused by a blow to the head or body, a fall, or another injury that jars or shakes the brain inside the skull.”3

In my opinion, below is the best definition, of course, when at a work picnic, or a luncheon at the local gala, this will make the listeners more confused, and you will appear pompous.

“Concussion is defined as any transient neurologic dysfunction resulting from a biomechanical force”4

Of course, Dr. Delashaw in episode 17 says that a concussion must involve a loss of consciousness which none of these definitions take into account. For the purposes of this post, we will leave this definition alone. I simply want to show the molecular mechanisms behind a head trauma injury so that you all can better explain it to friends.

Initially, when the neuronal cells of the brain received so much force, acute chemical changes occur within the brain.

Some of the shifts that occur are:

  1. Glutamate-excitatory neurotransmitter
  2. Potassium-requires energy to re-establish balance via Na/K pumps
  3. Lactate-due to increased glucose metabolism
  4. Glutamate-excitatory neurotransmitter
  5. CMRglucose– oxidative (aerobic) oxygen consumption goes up
  6. CBF (cerebral blood flow)- decreases as glucose consumption increases
  7. Calcium-high levels of Calcium are shown to cause mitochondrial failure via the opening of porins, leaking valuable molecules.5
  8. NOT SHOWN IN FIG: Magnesium- levels drop for up to 4 days post injury. This can negatively impact ATP production in mitochondria, and unblock NMDA channels which are in charge up transporting Calcium in neural cells.

Sources:

  1. Centers for Disease Control and Prevention: Heads up: Basics. Jan 31, 2017. No author listed.

Derived from: https://www.cdc.gov/headsup/basics/concussion_whatis.html

 

  1. Mayo Clinic. Patient Care and Health Information: Diseases and conditions: Concussion. No author listed.

Derived from: http://www.mayoclinic.org/diseases-conditions/concussion/home/ovc-20273153

 

  1. WebMD: Brain and Nervous System: Concussion. No author listed.

Derived from: http://www.webmd.com/brain/tc/traumatic-brain-injury-concussion-overview#1

 

  1. Giza, C. Hovda, D. 2001. The Neurometabolic Cascade of Concussion. The Journal of Athletic Training. 36(3): 228-235.

 

  1. Contreras, L., Drago, I., et al. 2010. Mitochondria: The calcium connection. Biochimica et Biophysica Acta (BBA) Energetics. 1797(6-6): 607-618

 

So now that we see what the physiological implications of a “concussion” are, it is essential to take a step back and see concussions in the bigger picture of all brain injuries. So I put together a flow chart that puts it all in perspective.