In the good old days as some people would call it, if you get hit in football or any sport and you were knocked out it was almost seen as a sign of weakness. No man went to the doctor to see what was actually going on in the brain, instead it was recommended to just “shake it off”. However, with the bombshell report that the National Football League was hiding research about concussions and the potential lifelong effects that could result from multiple concussions, the research has become abundant.
Before discussing the research it is important to see the scope of how many concussions actually occur in the United States every year. According to the Centers for Disease Control and Prevention (CDC) in 2013 about 2.8 million Americans were diagnosed with a Traumatic Brain Injury (TBI), most of them being mild TBI’s or as they are commonly known as concussions. These TBI’s accounted for 50,000 deaths in the United States alone. Among all the concussion diagnosed every year it is estimated that 70,000 people experience permanent damage to their brains. One interesting fact, is that the most common sport that causes concussions is not football, it is actually cycling. However, football still experiences just over 36,000 annually.
As a result of a concussion many problems can arise. Cytoskeletal damage can arise because the force of a concussion can cause the complex microstructural components formed by neurons and glia to be damaged. This damage to the cytoskeletal complex can also cause axon dysfunction. This means that the axons on neurons can be overstretched causing them to become overly porous to excitatory molecules. To the extreme end of this the axons can actually be snapped off at the axon hillock. This is severe because this prevents axons from sending action potentials and communicating with the rest of the brain. This can cause cognitive deficits and a lack of communication in the brain. One other main contributor the symptoms of a concussion is increased inflammation. The upregulation of cytokines and cytokine genes causes an increase in stress on neurons. This increased stress if it is prolonged can ultimately lead to cell death and an overall loss of neurons. Either way a concussion can be catastrophic, however what has arisen over the past several decades is the ability to see the effects of a concussion.
This is where the imaging arises. The first form of brain imaging is Diffusion tensor MRI (DT-MRI). It works by sensitizing the MRI signal to the random molecular motion of water molecules (diffusion) by addition of ‘diffusion encoding gradients’ to a standard MR pulse sequences. Water molecules are more likely to travel down white matter (neuronal pathways) than they are to leave these pathways. This allows you to visualize if any of these tracts are damaged, hence seeing if there is a concussion
The second method for visualizing TBI’s is functional magnetic resonance imaging or functional MRI (fMRI). This works by using MRI technology that measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases. So in essence decreased blood flow to a region of the brain would imply that there is damage to this area of the brain.
Based on the images above it is clear that concussions are not good for the brain and should be take very seriously. If you or someone you know has a concussion make sure to see a doctor to plot a course of action and an effective treatment.
