Recognizing Seizures & Photic Triggers

Recognizing a Photosensitive Occipital Lobe Epilepsy (POLE) seizure can be difficult because the symptoms often start with internal visual experiences that only the patient can see. Unlike a typical seizure that might start with a visible twitch, a POLE seizure begins in the brain’s visual center, often triggered by specific environmental light patterns ^[1][2].

Identifying Visual Symptoms

The earliest signs of a seizure are called elementary visual hallucinations ^[3]. These are simple, repetitive images that appear suddenly. Because they originate in the occipital lobe, they are often the very first thing experienced ^[2]. These auras can include:

• Photopsia: Brief flashes of light, bright spots, or sparks ^[3].
• Kaleidoscopic Patterns: Multi-colored circles or geometric shapes that may move across the field of vision ^[3][4].
• Visual Distortions: Objects appearing much larger (macropsia) or smaller (micropsia) than they actually are ^[2].

These symptoms are often confused with migraines, but epileptic visual symptoms are usually much shorter—often lasting only seconds to a couple of minutes—and are very consistent each time they happen ^[3][5].

Physical Signs and Progression

As the electrical activity spreads from the visual center to other parts of the brain, physical changes may occur. This is known as seizure progression ^[6].

1. Oculomotor Symptoms: The eyes or head may involuntarily turn to one side (ictal eye deviation) ^[7]. Fast, rhythmic eye movements called epileptic nystagmus can also occur ^[8].
2. Autonomic Changes: A sudden pale appearance, nausea, or vomiting can sometimes accompany the event ^[9][10].
3. Secondary Generalization: If the electrical “storm” spreads to the entire brain, the focal seizure can become a generalized tonic-clonic seizure, involving a loss of consciousness and rhythmic jerking of the arms and legs ^[11][6].

Seizure First Aid

If a focal aura progresses to a generalized tonic-clonic seizure, bystanders should follow basic seizure first aid:

• Stay calm and time the seizure.
• Ease the person to the floor and place something soft under their head.
• Turn them gently onto one side to keep their airway clear.
• Do NOT put anything in their mouth. (It is a myth that a person can swallow their tongue).
• Do NOT hold them down or try to stop their movements.
• Call 911 if the seizure lasts longer than 5 minutes, if they have difficulty breathing afterward, or if it is their first-ever generalized seizure.

Common Photic Triggers

POLE is a “reflex” epilepsy, meaning seizures are often a direct response to photic triggers—specific types of light or patterns ^[1]. These triggers can be found in everyday life:

Artificial Triggers

• Television and Video Games: Rapidly changing images, high-contrast patterns, or specific flicker rates on screens ^[1].
• Smartphones and Social Media: Rapidly scrolling through high-contrast feeds or videos with flashing effects is an increasingly common trigger for teens and young adults.
• Strobe Lights: High-frequency flashing lights found at concerts, dances, or in some emergency vehicle lights ^[1].
• Fluorescent Lighting: Sensitivity to the subtle, high-frequency flicker of faulty or older fluorescent bulbs.

Natural Triggers

• Flickering Sunlight: Sunlight shining through a row of trees while driving, or reflecting off moving water or snow ^[12][13].
• High-Contrast Patterns: Looking at repetitive patterns, such as a striped radiator or a black-and-white tiled floor ^[1].

Identifying these triggers is a key part of management. Your doctor may use Intermittent Photic Stimulation (IPS) during an EEG to determine exactly which frequencies of light (measured in Hertz or Hz) are most likely to trigger brain activity ^[14][15].