What is a Concussion?

A concussion is defined as a complex pathophysiological process that affects the brain, typically induced by trauma to the brain. It can be caused either by a direct blow to the head, or an indirect blow to the body, causing neurological impairments that may resolve spontaneously. Symptoms usually reflect a functional disturbance to the brain, and may include physical (e.g., headaches, nausea), cognitive (e.g., difficulty with concentration or memory), emotional (e.g., irritability, sadness), and ‘maintenance’ (e.g., sleep disturbances, changes in appetite or energy levels) symptoms. A concussion is considered a brain injury.


What happens to the brain during a Concussion?

The adult brain is a three pound organ that basically floats inside the skull. It is surrounded by cerebral spinal fluid, which acts as a shock absorber for minor impacts. When the brain moves rapidly inside the skull, a concussion has technically occurred. One common scenario that can lead to a concussion is a direct blow to the head or a whiplash effect to the body. The impact rapidly accelerates the head, causing the brain to strike the inner skull (i.e., the coup). When the head decelerates and stops its motion, the brain then hits the opposite side of the inner skull (i.e., the contrecoup). The second common scenario is a rotational concussion, in which the head rapidly rotates from one side to another causing shearing and straining of brain tissues. In either case, delicate neural pathways in the brain can become damaged, causing neurological disturbances.


Does age play a role in Concussion management?

There are distinct differences in age when it comes to managing sport related concussions. Recent research demonstrates that high school athletes not only take longer to recover after a concussion when compared to collegiate or professional athletes, but they also may experience greater severity of symptoms and more neurological disturbances as measured by neuropsychological and postural stability tests. It is also estimated that 53% of high school athletes have sustained a concussion before participation in high school sports, and 36% of collegiate athletes have a history of multiple concussions. Because the frontal lobes of the human brain continue to develop until age 25, it is vital to manage youth concussions very conservatively to ensure optimal neurological development and outcomes.


What role does Imaging (e.g., MRI, CT scans, etc.) play in Concussion management?
Imaging modalities like CT scans, MRIs, and PET scans are very effective in determining structural abnormalities in the brain after a traumatic injury. In fact, many concussion events that require a visit to the Emergency Department will involve an imaging test. Most imaging techniques can reveal skull fractures and internal bleeding and lesions on the brain, and they can be informational tests if the person is experiencing prolonged symptoms days and/or weeks following the injury. Despite the effectiveness of these types of imaging modalities to identify structural damage, concussions are often characterized by functional, neurometabolic damages in the brain and require other types of cognitive and postural stability tests to assess the severity and extent of any damage.


What is Neuropsychological Testing?
Neuropsychological testing has been used for over 30 years in the assessment of cognitive function after concussive injuries. Neuropsychological tests are designed to measure cognitive skills and abilities such as intelligence, problem solving, memory, concentration, impulse control, and reaction time, to name a few. At the Sports Concussion Institute, both computerized and standard paper-and-pencil tests are utilized to gather evidence-based, comprehensive data on cognitive functioning before (i.e., Baseline Test) and after (i.e., Post-Injury Test) a concussive injury occurs.


How do you determine that an athlete is OK to Return to Play?
Various factors contribute to the decision of returning an athlete to play after sustaining a concussion. With computerized neuropsychological testing procedures acting as the “cornerstone for concussion management”, patients at the Sports Concussion Institute will be administered an additional battery of tests that assess cognitive and neurobehavioral function. Additionally, patients at SCI will undergo vestibular balance testing which has been shown to be an effective, empirically driven approach to managing concussions. After a comprehensive interview, a full assessment of patient symptoms will take place. Because of the complex nature of concussions, a multi-factorial, multi-disciplinary approach must be taken to ensure the safety and well-being of the patient, and only after all these factors indicate that the athlete can safely participate in their sport will he or she be cleared for Returning to Play.


What are some risk factors for sustaining a sport-related concussion?
A major determinant of sport-related concussions is an athlete’s prior history of concussions. Research suggests that if someone has already received one concussion, they are 1-2 times more likely to receive a second one. If they’ve had two concussions, then a third is 2-4 times more likely, and if they’ve had three concussions, then they are 3-9 times more likely to receive their fourth concussion.Some studies have shown that females are more likely than their male counterparts to sustain a concussion, and they tend to have more symptoms and require more time to recover. Various neuroanatomical and biomechanical differences exist between the genders in sports that could contribute to these differences.Additionally, a history of developmental disorders, psychiatric disorders, or a history of headaches or migraines can play a part in concussion recovery time. Research suggests that for every concussion, the person is 1-2 times more likely for a second; 2-4 times more likely for a third; and 3-9 times more likely for a fourth. the factors contributing to concussions and their recovery is regularly revealing new information, and it’s important that the people responsible for the health of the athletes stay up to date on the latest research on prevention and treatment.


What are some long-term consequences of multiple concussions?
Long term effects of multiple concussions are currently being studied by researchers around the globe. Not only can multiple traumatic incidents contribute to the development of mild cognitive impairments (MCI’s), chronic traumatic encephalopathy (CTE), and other adverse outcomes, but a storied concussion history can also cause post-concussion syndrome (PCS). While we are still elucidating the causes of these long term effects, it is imperative that a person fully recover from one concussion before risking a subsequent one. Failing to do so adequately can lead to additional neurologic damage. Given this new understanding, managing concussions requires specialized, comprehensive and state-of-the-art approaches.


Concussion Facts
  • Children from birth to 9 years commonly sustained injuries during playground activities or while bicycling.1
  • 71.0% of all sports- and recreation-related TBI emergency department visits were among males.1
  • 70.5% of sports- and recreation-related TBI emergency department visits were among persons aged 10-19 years.1
  • For males aged 10-19 years, sports- and recreation-related TBIs occurred most often while playing football or bicycling.1
  • Females aged 10-19 years sustained sports- and recreation-related TBIs most often while playing soccer or basketball or while bicycling.1
  • National surveillance in 9 high school sports:2
  • TBI represents almost 9% of all injuries reported in the 9 sports
  • Numbers and rates are highest in football (55,007; 0.47 per 1000 athlete exposures) and girl’s soccer (29,167; 0.36 per 1000 athlete exposures)


  1. Gilchrist J, Thomas KE, Xu L, McGuire LC, Coronado VG. Nonfatal sports and recreation related traumatic brain injuries among children and adolescents treated in emergency departments in the United States, 2001-2009. MMWR 2011: 60(39); 1337-1342.
  2. Gessel LM, Fields SK, Collins CL, Dick RW, Comstock RD. Concussions Among United States High School and Collegiate Athletes. J Athletic Train. 2007; 42(4): 495–503.

*This information was obtained from the CDC website. For further information please see: