NVISION Centers

Your Eyes & Epilepsy – Critical Knowledge

10 sources cited

Last Updated

An epileptic seizure will make a person’s eyes react in distinct ways, such as uncontrollable fluttering, staring, or jerking movements. Some people experience visual hallucinations or auras.

Researchers have noticed that the eyes can be examined for information about the seizure after it happens, giving them clues as to how the disturbances in the brain develop. The effects on the eyes can also help doctors distinguish between epileptic and non-epileptic seizures.

How Epilepsy Affects the Eyes

Epilepsy is a neurological condition where abnormal electrical activity in the brain, largely due to chemical changes, causes recurring seizures.

Seizures that are caused by epilepsy are not known to affect vision, but it is quite common for patients to experience a number of changes to their vision immediately before and during a seizure.

This is because epilepsy affects different lobes of the brain. Depending on which region of the brain is producing the chemical changes that cause the abnormal electrical activity, the effects on the eyes might present themselves in different ways.

Effects include:

  • Rapid blinking.
  • Staring into space, unable to process visual stimuli.
  • Loss of field of vision.
  • Visual hallucinations.
  • Eye deviation.

Visual Disturbances

If a seizure originates from the occipital lobe, this is likely to cause visual disturbances. A person experiencing this type of seizure might show a rapid flickering of their eyes, forced closure of the eyelids, and the eyelids uncontrollably jerking.

Visual hallucinations can show up as the person seeing flashing lights, colors, or unusual patterns in their field of view, when no such visual stimuli are actually present. These can appear as simple shapes or colors, but they can also look very complex, such as seeing people, animals, or even fully developed scenes. In 2016, for example, the Epilepsy and Behavior Case Reports journal featured a case study of a man who had “cinematographic hallucinations,” where he would see distorted images of people in color, as if he was looking at “frames in an old movie.”

Auras

So-called focal seizures are often preceded by auras, when the patient experiences a light or smell before the seizure commences. It is believed that the aura is caused by the abnormal electrical activity taking place in the brain, implanting the perception of a light or smell when none is actually present.

While the patient experiences the aura, bystanders may notice other symptoms, such as the patient staring off into the distance, blinking rapidly, or jerking the eyes back and forth, all while being unresponsive to others.

Perceptive Illusions

eyelash closeup

There are also perceptive illusions (examples include macropsia, micropsia, and depersonalization), where the patient can “see” their body image from a third-person perspective. In rare cases, patients experience what is known as Alice in Wonderland syndrome, where they perceive a stationary object moving away from them or again see some kind of out-of-body visual experience.

Seizures that take place in the visual processing centers in the brain (within the cerebral cortex) are associated with palinopsia, which is the persistent perception of visual images after a stimulus is removed (also known as visual perseveration). In other words, people continue to see the image of an object that they had just been looking at, even after they cannot see it any more.

Versive Movements & Photosensitivity

Deviations of the eyes are also associated with seizures that affect the occipital lobes and other lobes of the brain that regulate eye movement and vision. This results in what is known as versive movements, where the eyes (and/or other parts of the body) are forced into an involuntary and unnatural position, sometimes for a long period of time.

Photosensitivity is another common visual symptom of an epileptic seizure. A sensation of a bright, blinding light, or a negative reaction to such a light, is a frequent sign of the onset of a seizure for many people.

What the Eyes Can Tell Us About Epilepsy

One effect of epileptic seizures having such a pronounced effect on the eyes is that it might give doctors a way to detect brain inflammation and its own impact on seizures. The Journal of Neuroinflammation suggested that the immune response in the eyes can offer a noninvasive way of seeing the parts of the brain where seizures start, in as little as six hours after the seizure. Animal experiments found an increase in the number of specialized immune cells in the central nervous system, as well as an increase in the amount of certain cytokines, signaling molecules produced by cells in the immune system.

The researchers writing in the study concluded that epileptic seizures induce a particular immune response in the eyes, which further suggests that measuring the degree of that inflammation can be a noninvasive way for detecting brain inflammation.

This is promising. Although epileptic seizures have long been suspected to cause an immune response in the brain, the mechanism of that was not fully understood. By seeing what an epileptic seizure does to the eyes, scientists can work backwards to better understand the full scope and impact of epilepsy on the affected regions of the brain.

Epileptic vs. Psychological Seizures

Another way the eyes can help with the understanding of seizures is by looking at the movements of the eyes themselves during an epileptic episode. Researchers writing in the Neurology journal looked into whether a patient’s eye movements during their seizure can distinguish whether the seizure is caused by epilepsy or due to another (psychological) reason.

The key is whether people experiencing the seizure closed their eyes or not. Fifty patients having non-epileptic seizures closed their eyes during the episode, while 152 patients experiencing epileptic seizures either kept their eyes open or blinked repeatedly until the episode reached its conclusion.

The difference will help doctors and first responders make a more accurate and quicker diagnosis when attending to a patient who experiences a seizure. This will also help in proper prescription protocols. Approximately 33 percent of patients with an epilepsy diagnosis do not respond to anti-seizure drugs, which might be because their seizures are not epileptic in origin.

While epileptic seizures are caused by abnormal chemical and electrical activity in the brain, psychological seizures are attributed to severe mental health disorders. However, the actual seizures look very similar. Medical News Today explains that psychological seizures are “easy to misdiagnose,” which often leads to an incorrect diagnosis and treatment.

Improving Seizure Diagnoses

Before the finding that the eyes can be used to tell epileptic seizures apart from psychological seizures, it would take up to nine years for patients who had psychological non-epileptic seizures to receive a corrected diagnosis. Psychological seizures are not very well-known, so even neurologists would be more likely to suspect epileptic seizures, often prescribing anti-epileptic drugs for years on end, all while the patient continues to experience seizures.

But now, by making the connection with the eyes, researchers are hopeful that incorrect diagnoses can be adjusted sooner in the process. This will help many patients avoid almost a decade’s worth of unnecessary medication and stress.

The information provided on this page should not be used in place of information provided by a doctor or specialist. To learn more, read our Privacy Policy and Editorial Policy pages.