Light sensitivity or photophobia is an abnormal intolerance to light. It is a common symptom in both acute and chronic concussion sufferers, affecting around 40% of concussed individuals. Though it is usually most severe in the first few weeks following a head injury, it may persist for much longer in some cases. Prolonged cases are especially likely if one fails to seek treatment within the first week or so after sustaining their head injury.
If you are experiencing light sensitivity, read further for guidance on understanding, managing, and recovering from this and other associated symptoms.
Light sensitivity can manifest in a variety of ways. Some individuals may experience discomfort or pain when exposed to bright lights, while others may have difficulty adjusting their eyes from darkness to light. Further, light sensitivity may also be an underlying cause of symptoms like headaches, nausea, and dizziness. As such, it is rare that light sensitivity presents as a standalone symptom and is more likely to be part of a more comprehensive symptom profile.
There are many different contexts where you may notice indications of light intolerance.
You may, for instance:
Do any of these sound familiar? If you can relate to these or have had any other experiences of light intolerance after sustaining a head injury, here are your first few take-home points:
Let’s now look at some potential causes of this troublesome symptom.
There are a number of ways post-concussive light sensitivity may develop. Let’s look at a few of the most common causes.
The existing scientific literature well establishes that a common consequence of concussion is autonomic dysregulation. The autonomic nervous system controls functions that we aren’t aware of (i.e., involuntary), such as heart rate, blood pressure, and breathing. Another important function, particularly relevant to photophobia, is the regulation of pupil size.
As a result of this dysfunction of the autonomic nervous system, concussion sufferers will often experience increased “sympathetic tone”—or, to put it more colorfully, their “fight or flight” switch gets flicked on and stuck there—and the result is, among other things, persistent dilation of the pupils.
Now, throughout your day, your pupils are constantly adapting to the light in your environment, emotional state, etc., and regulating how much light can enter your eye to strike your retina (which is like the nerve-ending of your optic nerve that goes directly into the vision-related centers of your brain). When your pupils become “stuck” wide open due to your body being “stuck” in fight or flight mode, too much light enters the eye, and discomfort is the unsurprising result.
Another potential cause is dysfunction of your vestibular system, which is located in your inner ear and provides information about your body’s location in space, among other things.
Working alongside the inner ear vestibular system, the senses of sight (i.e., your eyes) and touch (i.e., the nerve endings in your skin) provide information about your body’s location in space. In a healthy person, these three systems provide a harmonized reading of where your body or parts of your body are in relation to each other and external things in your environment.
It is not hard to imagine how a solid impact on the head may affect the structures and functions of the inner ear. If this happens, the vestibular system falls out of sync with the other two systems, which results in inconsistent information for the brain to interpret spatial position.
With vestibular dysfunction, your eyes (i.e., the visual system) may try to do more—that is, they may overcompensate—to compensate for the “garbled information” (that’s a technical term) from the inner ear. This ramping up of the visual system to overcompensate for the compromised vestibular system may result in light sensitivity.
Some parts of your brain are more involved with vision than others.
A concussion may directly affect the parts of your brain that impact your visual system. Two common parts of the brain that may be affected by concussion and, consequently, compromise the function of the eyes are the superior colliculus and the thalamus.
The superior colliculus is responsible for orienting to specific visual information (e.g., threat) and executing specific eye movements. If your superior colliculus is compromised, you may experience difficulty with visual tracking (i.e., following an object with your eyes as it moves), which can result in light sensitivity.
The thalamus serves as a relay station between the different parts of the brain involved in vision. Damage to the lateral geniculate nucleus of the visual thalamus may disrupt communication between these regions and lead to visual perception and processing issues, which could also contribute to light sensitivity.
Let’s now look at three key steps to reduce and eventually eliminate light sensitivity. These essential steps include:
This may be the most crucial step you take along your path to concussion recovery. The fact is, concussions are complex phenomena that can be very difficult to manage on your own. Having a trained clinician to accompany and guide your recovery process will not only speed up your recovery time but will reduce the anxiety and frustration that often result from such an injury.
As we have already said, it is often the case that concussion sufferers experience a multitude of symptoms. This can drastically affect your quality of life and impact your ability to participate fully in school, work, and sports. It may even have a detrimental effect on the most basic activities of daily life. You do not — indeed, you should not — face these obstacles alone!
Start your path to recovery by finding a good clinician.
Recent research strongly indicates that presenting early to a clinic that provides up-to-date concussion care improves prognosis significantly. One recent study, for instance, concluded that “athletes who were evaluated within a week of injury recovered, on average, 20 days faster than those athletes seen 2 to 3 weeks post injury.” Other studies corroborate this finding with recovery times ranging from 56 to 110 days sooner.
Why does early intervention have such an impact? Well, as we have already noted, concussion often results in a cascade of multiple, diverse symptoms. Though initiated through forces to the brain, concussion is best understood as a “whole person” condition as it typically affects numerous aspects of the person simultaneously —neurological, circulatory, endocrine, and psychological, to name a few.
A properly trained clinician will immediately initiate a multimodal care plan, simultaneously treating most or all of the potentially compromised systems. Moreover, early consultation will ensure patients avoid exacerbatory behaviors such as absolute rest or excessive physical activity. Due to such factors, the existing research points clearly toward an expedited recovery for those who see their concussion specialist as soon as possible following the injury.
Understanding concussion as merely a “head injury” or understanding photophobia as simply an “eye problem” may lead to an inadequate plan of care.
Acknowledging mental health is one easily overlooked but critical part of concussion management.
Think about this for a moment: how you see the world through your eyes can significantly affect how you feel about it. A symptom like light sensitivity can change your perception of the world. For example, many individuals may experience anticipatory anxiety about bright lights when making trips to the grocery store or going into their office for work.
The additional stressors brought on by persistent eye pain, headaches, nausea, vertigo, and other concussion-related symptoms also make it more likely that you will experience emotional lows such as anxiety and even depression related to concerns about these symptoms and uncertain recovery. Such psychological barriers can be just as formidable as obstacles of a more physiological nature.
It is vital for you to speak openly about the effects that your concussion is having on your life with your loved ones so they understand what you’re going through, both mentally and physically.
Maintaining a social life is very important, even when modified to accommodate your symptoms and capacity.
Speaking openly and honestly about your feelings with your healthcare provider is equally important. This, too, will help them tailor a treatment plan that considers not just your physical well-being but also your mental and emotional state.
Relaxation techniques such as deep breathing, low stimulation, and meditative practices can help reduce the physical symptoms of light sensitivity by promoting a sense of calmness and reducing overall stress levels.
Avoiding or minimizing exposure to bright lights is an obvious but important step in managing light sensitivity.
While it is recommended that you wear sunglasses outdoors when dealing with light sensitivity, it is not recommended that you wear sunglasses indoors. Counterintuitively, while wearing sunglasses indoors may provide some relief, they may also hinder your recovery.
Your body systems are very good at adapting to stressors to better accommodate the stressors (e.g., think of your muscles getting stronger from lifting weights). So, your eyes and nervous system need “practice” responding to light in a controlled environment to reacquire their ordinary function. As such, some degree of light stress is appropriate for those with photophobia after a concussion.
That being said, wearing sunglasses indoors occasionally for short periods on really bad days may be permitted (ask your clinician).
And how about screen time? Generally speaking, time spent exposed to smartphones, television, computers, and other screens should be moderated in concussion patients. Because digital technology has become a massive part of our lives, we don’t quickly realize the high demand screen activity places on our visual systems and the relevant centers in our brains.
For those suffering from photophobia, backlight intensity and frenetic screen activity (including scrolling and swiping!) can cause a lot of strain. In addition to limiting such exposure, dimming your room’s light, wearing blue light filtering glasses, wearing colored lenses, or using non-LCD screens may be helpful.
As the research continues to pour in on concussion management, it has become increasingly clear that exercise plays a critical part in symptom resolution. You will likely benefit from light exercise within a day or two of being concussed, provided it is low risk and does not exacerbate your symptoms significantly.
One of the best ways to recover from autonomic dysfunction after a concussion is to exercise. But of course, if you are suffering from symptoms like light sensitivity and/or headaches, exercise might be the last thing you feel like doing. This is why seeing your clinician, who will help establish an exercise plan through a Buffalo Concussion Treadmill Test, is essential. This will allow the clinician to accommodate your present condition and will also enable adjustments in your exercise plan as your symptom presentation improves or changes.
Light sensitivity can be a very unpleasant experience for those who have suffered from concussion. But much can be done to ensure a quick and complete recovery. Start by finding a good healthcare provider who specializes in concussion management. While they will tailor a plan of care designed to meet your specific needs, there is much you can do — as this article has shown — to expedite the resolution of your symptoms.
So, don’t wait to get started. Once you do, you can be sure recovery is coming!
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