A concussion is a neurologic injury that causes a temporary disturbance in brain cells, as a result of extreme acceleration or deceleration of the brain within the skull. The common misconception is that you must be hit in the head to cause a concussion injury – this is not true! Because a concussion is the result acceleration or deceleration of the brain, a concussion can happen with a significant blow to anywhere on the body, provided sufficient acceleration/deceleration is transmitted to the brain tissue.

The brain cell disturbance causes the brain cells to discharge uncontrollably which may cause any one, or more of the following signs or symptoms:

    • Loss of consciousness (Not necessarily – over 90% of concussions DO NOT result in a loss of consciousness)
    • Headache
    • Pressure in the head
    • Neck pain
    • Nausea or vomiting
    • Dizziness
    • Blurred vision
    • Balance problems
    • Sensitivity to light
    • Sensitivity to noise
    • Feeling slowed down
    • Feeling of “fogginess”
    • Not feeling right or feeling off
    • Difficulty concentrating
    • Difficulty remembering
    • Fatigue or low energy
    • Confusion
    • Drowsiness
    • Trouble falling asleep
    • More emotional
    • Irritability
    • Sadness
    • Nervous or anxious

If you, or your child is experiencing ANY of the symptoms above following a significant hit or blow to the head or body, you should have a high suspicion of a concussion injury.

The massive discharging of brain cells will likely calm down in a very short period of time and the patient may even feel better after a few minutes to an hour after injury. Don’t be fooled by this improvement, as there is a second phase to a concussion known as “Spreading Depression”. The initial brain cell discharge creates an imbalance within the cells of the brain, that ultimately leads to an energy deficit as the cells frantically use up all of their energy stores to reset the normal balance. These energy stores will continue to decline over the next 3-7 days. Anyone who has been around someone who has suffered a recent concussion, or has had a concussion themselves, will attest to the fact that the injured person is extremely fatigued, irritable and emotional; similar to a tired and cranky child. This is because their energy levels are depleting. This is also why the first step in dealing with any concussion is always rest, which helps to conserve energy stores and potentially help with recovery.

The second phase of the concussion is actually the most dangerous. When someone is in this low energy state, another blow, even one of much lower magnitude, can cause another concussion. Because the energy levels of the brain are already severely depleted, another concussion can cause extreme energy depletion, which may cause permanent death of the involved brain cells, potentially causing permanent disability, or in some instances, death of the individual.

On the other hand, the research has shown that if the brain has fully recovered from an energy standpoint and the person receives another concussion, there is no evidence of an additive effect. This means that it may not be the NUMBER of concussions an individual suffers but rather the way each injury is managed that is the major determining factor for long-term problems due to concussions.

The major problem with concussions is that symptoms, meaning how someone feels, does not coincide with the energy levels in the brain. Most people feel better long before their brain has recovered to the point that they are actually safe to return to their sport. Unfortunately, there is no scan, MRI, or X-ray that can detect a concussion. This is where the benefits of baseline testing come in. For more information on baseline testing, please click here.

This post is also available in French