Concussion 101

Want to know more about concussion? We've put together some great information in this post to introduce you to the topic. Welcome to Concussion 101!

Questions addressed in this class:

  • What is a concussion?
  • How do I know if I’ve had a concussion?  What are the signs?
  • I’ve had a concussion, what should I do?
  • What can I expect my recovery to look like?  What is the prognosis?
  • What can I do about it?  What are the best ‘self-help’ options?
  • What can medical and rehab professionals do about it?
  • What if I don’t get better?

What is a concussion?

Concussions are mild traumatic brain injuries that can happen when your brain moves around quickly inside your head.  This can happen when you hit your head (or something else hits it) or if you experience jolting or shaking of the head (like in whiplash).  You don’t need to have an impact directly to your head or lose consciousness to experience a concussion.  

If you’ve had a concussion several things happen right away:

  1. Your brain neurochemistry changes
  2. Individual brain cells might not work as well or talk to each other as effectively
  3. Blood and oxygen circulation in your brain might change
  4. Connections or networks through your brain might get a little mixed up
  5. Your system starts to try to repair things which involves inflammation and uses up lots of energy

*You might also have hurt other parts of your body in the injury too, like your neck, nerves, and parts inside your inner ear that are important for balance.  It's important that these areas don't get forgotten about.

How do I know if I’ve had a concussion?  What are the signs?

Everyone’s experience after having a concussion is different.  In general symptoms might include:

Headache Irritability & agitation Feeling “slowed down”
Nausea Depression / sadness Feeling “in a fog” or “dazed”
Vomiting Anxiety / nervousness Difficulty concentrating
Blurred or double vision More emotional Difficulty remembering
Seeing stars or lights Difficulty sleeping, or Difficulty word finding
Balance problems Excessive sleepiness Impaired judgment or control
Dizziness Apathy Confusion
Sensitivity to light or noise Cognitive fatigue
Tinnitus Intolerance for exertion
Pressure in the head
Fatigue / drowsiness
Intolerance to exertion

If you’ve experienced a hit or jolt of the head and begin to experience any of the symptoms above it is important to see a doctor who can help make a diagnosis.  In most cases a concussion is diagnosed when there is a history of some kind of force to the brain and symptoms like those listed above emerge.  Keep in mind you don’t need to lose consciousness or have amnesia to have a concussion, and it won’t show up on a CT or MRI scan.

Concussion symptoms are normally temporary and get better over time. In most cases they resolve in a few days or weeks.  If symptoms start getting worse, or if you experience any of the following, seek out medical help right away (we call these “Red Flags”):

RED FLAGS: if your symptoms increase or you experience the following, seek additional medical help: Fainting, falling or blacking out, drowsiness, or can’t be woken up / A constant severe headache or a headache that gets worse - Repeated vomiting or throwing up / Can't remember new events, recognize people or places (increased confusion) / Acting strange, saying things that do not make sense (change in behaviour) / Having a seizure (any jerking of the body or limbs) / Inability to move parts of your body, weakness in arms or legs, or clumsiness / Double vision, worsening of vision or slurred speech

It's also important to keep in mind that other injuries might happen along with a concussion, and concussion symptoms are similar to many other disorders.  So seeing a doctor is very important to rule anything else out.  Other conditions that might occur along with a concussion, or present with similar symptoms include:

  • Depression
  • Anxiety or PTSD
  • Chronic Pain
  • Peripheral nerve injury / neuropathy 
  • Whiplash Associated Disorders, or other soft tissue injury
  • Chronic headache or migraine
  • Middle or inner ear injury (eg. BPPV)
  • Ocular / oculomotor injury
  • Cervical spine injury or dysfunction
  • Spinal cord concussion (SCC) or spinal cord injury (SCI)
  • Neuroendocrine dysfunction (NED)
  • Other conditions like fractures, dislocation, stenosis, lesions, tumors/cancer, circulatory conditions, metabolic issues, drug interactions.
When in doubt, see a doctor to rule it out.


    I’ve had a concussion, what should I do?

    The approach to treating and recovering from concussion is straightforward:

    1. Physical and cognitive rest - right after an injury has happened and for the first few days rest is the most important treatment.  Consider taking time off school and work or reducing demands, and do not play sports.  You should limit physical, cognitive and emotional activity as much as possible.  Light activities like walking around the house are okay if they don’t make symptoms worse.

    2. Seek out help and guidance from medical professionals, especially your doctor.

    3. Gradual, graded return to activity - after symptoms have settled over the first few days, it’s time to get gradually get moving and back to life.  With your doctor or healthcare team’s support: start with light, easy activities (walking, chores, watching TV or using computer) but only if they don’t make symptoms worse.  Gradually increase level of activity over time, only progressing if symptoms are manageable.  Don’t push too hard!


    • Absolute rest (eg. laying in bed in a dark room doing nothing) is not necessarily helpful unless you’re very sensitive after concussion.  The goal is to maintain some level of activity but be safe and keep it within your symptom tolerance. See our other posts on meaningful rest.
    • If your symptoms worsen, seek out medical help.
    • Return to activity should be gradual and slow with no big changes in activity level.  See our posts on return to activity for more information.
    • If symptoms don’t start getting better, it may be time to seek out extra help and assessment.

    What can I expect my recovery to look like?  What is the prognosis?

    Recovery time is unique to each person and depends on many different factors, but in general the prognosis is very good and you may feel better within the first few days or weeks.  It’s not unusual for symptoms to last longer, so don’t get discouraged if you’re still dealing with symptoms after months or even years.  Many of the symptoms of concussion are due to changes in brain cells, connections and networks in the brain which all can change and heal over time. Brains have an amazing ability to rewire and heal through what’s called neuroplasticity.

    What can I do about it?  

    There are a ton of things you can do to recover well - see our article 10 things you can do for yourself to heal after a concussion.

    What can my medical professionals do about it?

    Although most symptoms of concussion will get better on their own through strategic rest and gradual return to activity, it’s really important to have medical oversight and support. It can be very difficult to manage all of your symptoms alone.  Medical and rehabilitation professionals can help in the following ways:

    • Diagnose and confirm a concussion has happened, and make sure other serious conditions aren’t present too (like a more serious brain injury, fractures, bleeding, nerve injury, etc...)
    • Assess and figure out what is causing your particular symptoms so they can be treated more specifically
    • Differentiate the cause of your symptoms, and rule out other related or similar conditions (like depression, anxiety, migraine, whiplash / neck issues, neurological injury, etc...)
    • Monitor your recovery and adjust treatment as needed
    • Provide referrals to specialists if needed (eg. neuropsychologist, neurologist, sports medicine)
    • Provide support and guidance about how to rest and return to activity
    • Design a specific return to activity plan for you so you can return to your life activities in the safest and most efficient way possible
    • Treat cognitive symptoms like issues with attention, memory and processing
    • Treat physical symptoms, and other related injuries like whiplash and pain.
    • Treat psychological symptoms like anxiety, PTSD and depression
    • Treat visual issues like blurred or double vision, issues with reading and eye tracking
    • Treat dizziness or vestibular symptoms like impaired balance and falling.
    • Coordinate a successful return to sport, school and work
    • Design a safe and effective exercise program
    • Improve your sleep and energy levels
    • Help you or your family and friends to learn more about concussion and the neurobiology of the injury

    What if I don’t get better?

    In the vast majority of cases people make full recovery after concussion.  Some people do continue to struggle with symptoms for months and sometimes years - but most live full and normal lives even in the face of symptoms.  The key message is this: even if you have been dealing with symptoms for years, there is always room for improvement.  Sometimes it just takes a fresh approach, or more healing time.


    1. Barkhoudarian, G., Hovda, D. A., & Giza, C. C. (2016). The Molecular Pathophysiology of Concussive Brain Injury–an Update. Physical medicine and rehabilitation clinics of North America, 27(2), 373-393.

    2. Giza, C. C., & Hovda, D. A. (2001). The neurometabolic cascade of concussion. Journal of athletic training, 36(3), 228.

    3. Giza, C. C., & Hovda, D. A. (2014). The new neurometabolic cascade of concussion. Neurosurgery, 75(0 4), S24.

    4. Leddy, J. J., Kozlowski, K., Fung, M., Pendergast, D. R., & Willer, B. (2007). Regulatory and autoregulatory physiological dysfunction as a primary characteristic of post concussion syndrome: implications for treatment. NeuroRehabilitation, 22(3), 199-205.

    5. Signoretti, S., Lazzarino, G., Tavazzi, B., & Vagnozzi, R. (2011). The pathophysiology of concussion. PM&R, 3(10), S359-S368.

    6. Ontario Neurotrauma Foundation (2013)  Second Edition of the Guidelines for Concussion/Mild Traumatic Brain Injury and Persistent Symptom