Post-Concussion Syndrome: When Symptoms Like Light Sensitivity Last Long after a Concussion

Post-Concussion Syndrome: When Symptoms Like Light Sensitivity Last Long after a Concussion

Posted by Greg Bullock on 9th Feb 2017

The potential long-term impact of concussions on youth and professional athletes have brought traumatic brain injury into the national dialogue recently. Anyone, from children to military veterans, who experiences a head injury can have a concussion, not just athletes Although most head injuries heal with little difficulty shortly after they occur, some can result in persistent medical issues and complications. When symptoms—such as headaches and light sensitivity— persist for months and even years after a concussion, it’s called post-concussion syndrome.

Concussion vs Post-Concussion Syndrome

What is a concussion or mild TBI?

A concussion, also referred to as a mild traumatic brain injury (TBI), occurs when an individual suffers a hard, sudden impact to the head. Although spinal fluid acts as a cushion, the brain can still shift within the skull and suffer bruising or bleeding. Nerve tissue can be damaged through shearing forces that move different portions of the brain at varying speeds. Additional chemical imbalances may hinder nerve cell function, which is believed to be one of the contributing factors for loss of consciousness, according to medical experts. The damage that occurs in and against the brain during a concussion is not directly correlated with the intensity of the impact either; the location of the injury as well as the existence of prior concussions can play a role. And any head injury—no matter how mild—can cause disruptive symptoms that may linger.

Who is likely to experience a concussion?

High-contact sports such as football, soccer, and lacrosse are often thought of the main source of concussions. An estimated 1.6 million to 3.8 million concussions are caused by sports and recreational activities each year, according to the Brain Injury Research Institute. Falls; car, motorcycle, or bicycle accidents; fights; and physical assault are some other causes of concussions.

Members of the military have greater susceptibility to concussion-related trauma as a result of blasts, motor vehicle accidents and gunshot wounds. The Department of Defense and the Defense and Veteran's Brain Injury Center estimate that nearly a quarter of all Iraq and Afghanistan casualties resulted from brain injuries, higher than other comparable military conflicts. Further research from Defense and Veteran’s Brain Injury Center showed an increasing trend of first-time TBI diagnoses (most of which were classified as mild TBI/concussions) among active duty service members from 2000-2011, peaking to nearly 33,000 per year.

Signs and symptoms of concussion

It is not always easy to identify when a person has been concussed, but there are numerous signs and symptoms for which you can be on the lookout:

  • Headaches or a "pressure-like" feeling
  • Dizziness or instability when standing or walking
  • Loss of consciousness (brief or long-lasting)
  • Extreme fatigue
  • Insomnia
  • Emotional changes (anxiety, irritability)
  • Mental confusion, inability to focus, memory loss
  • Nausea, vomiting
  • Slurred speech, inability to answer questions
  • Vision changes (blurriness, seeing double)
  • Sensitivity to light and sound
  • Ringing in the ears

What is post-concussion syndrome?

Post-concussion syndrome (PCS) happens when symptoms persist for an extended period of time due to the functional impairment of the brain and nervous system. Currently, there is no clear medical definition for how long they must last before PCS is diagnosed. This can lead to confusion about which of the above symptoms are the result of the initial impact and which are part of a post-concussive condition. Generally speaking, if new symptoms arise or existing ones persist or worsen for weeks or even months after an injury, the development of post-concussion syndrome is highly likely.

Researchers have suggested1 that between 10-20% of people who suffer a concussion experience post-concussion syndrome, with most having symptoms that last anywhere from a few days to three months. For some individuals, these painful issues may even last up to a year or longer. Veterans may be even more likely to endure post-concussive symptoms for a longer time period when compared with civilians, in some cases up to 18 to 24 months, according to the Defense and Veteran’s Brain Injury Center.

Post-Concussion Syndrome Light Sensitivity

One of the most common symptoms of concussion and post-concussion syndrome is photophobia, or painful light sensitivity. Some common symptoms of TBI and concussion light sensitivity include:

  • Eyestrain
  • Vision fatigue
  • Squinting
  • Headaches
  • Eye pain
  • Inability to tolerate bright lights (especially fluorescent)

The International Brain Injury Association reports that those with post-concussion light sensitivity may also experience indirect symptoms such as vertigo, fatigue, and difficulty multitasking. Furthermore, studies show2 that photophobia is most severe 7-19 days after an injury, but light sensitivity could last up to 6 months after a concussion and others may even experience it indefinitely.

Treatment of Concussion-Related Light Sensitivity

In addition to simple methods such as reducing electronic screen time to counteract eyestrain and fatigue, the American Academy of Ophthalmology (AAO) recommends treating light sensitivity through the use of special photophobia glasses tinted with FL-41; these are effective because they target the harmful wavelengths found in fluorescent lighting and other common sources. TheraSpecs are the best glasses for light sensitivity, with its precision tint helping reduce photophobia, lessen eye strain and allow for greater light tolerance for the majority of the thousands who try them.


1Committee on Sports-Related Concussions in Youth; Board on Children, Youth, and Families; Institute of Medicine; National Research Council; Graham R, Rivara FP, Ford MA, et al., editors. Sports-Related Concussions in Youth: Improving the Science, Changing the Culture. Washington (DC): National Academies Press (US); 2014 Feb 4. 4, Treatment and Management of Prolonged Symptoms and Post-Concussion Syndrome. Available from:

2Digre KB, Brennan KC. Shedding Light on Photophobia. Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology Society. 2012;32(1):68-81. doi:10.1097/WNO.0b013e3182474548.

Secure Shopping

60-day return guarantee

Free shipping on US orders