During a seizure, a large group of brain cells fire electrical signals all at once in an uncontrolled, synchronized burst instead of taking turns in their normal rhythm. This disrupts the brain’s ability to process information, control muscles, or maintain awareness, depending on which part of the brain is affected. Up to 10% of people worldwide will experience at least one seizure in their lifetime, so this is far more common than most people realize.
What’s Happening Inside Your Brain
Your brain cells communicate through a careful balance of signals that excite neighboring cells and signals that quiet them down. A seizure happens when that balance tips dramatically toward excitation. Neurons that would normally fire independently start firing together in a massive, synchronized wave. Think of it like a stadium crowd: normally everyone is having separate conversations, but during a seizure, thousands of neurons suddenly start chanting in unison.
This abnormal firing can stay confined to one area of the brain or spread across both hemispheres. Where it starts and how far it travels determines what kind of seizure you experience and what it looks and feels like from the outside.
The Four Phases of a Seizure
Not every seizure follows the same pattern, but many move through up to four distinct stages.
Prodrome
Hours or even days before a seizure, some people notice subtle changes: irritability, a sense of unease, difficulty concentrating, or sleep disruption. Not everyone experiences this, and it can be easy to miss in hindsight.
Aura
The aura is technically the very beginning of the seizure itself, though many people think of it as a warning. It typically lasts 5 to 30 seconds and can produce vivid sensory changes. Some people smell something burning, sulfur, or even something oddly specific like peanut butter or toothpaste. Others taste something metallic, feel a wave of déjà vu, see flashing lights or images, hear sounds like ocean waves, or get a rising feeling in the stomach. Fear or anxiety can also hit suddenly. Most people who get olfactory auras describe the smell as unpleasant, though a few smell something neutral or even pleasant, like flowers.
The Seizure Itself (Ictal Phase)
This is the main event. What happens depends entirely on the type of seizure.
Recovery (Postictal Phase)
After the electrical storm passes, the brain needs time to reset. This recovery period averages 5 to 30 minutes but can stretch to several days after severe seizures. Common symptoms include confusion, exhaustion, headache, muscle soreness, memory gaps, difficulty speaking, and mood changes like anxiety or agitation. Some people feel embarrassed or emotionally fragile. More severe seizures can cause temporary hallucinations, delirium, nausea, irregular heartbeat, or elevated body temperature.
What Different Seizure Types Look and Feel Like
Tonic-Clonic Seizures
This is what most people picture when they think of a seizure. It unfolds in two stages. The tonic phase lasts roughly 10 to 30 seconds: muscles suddenly stiffen, the person loses consciousness, and they fall. A groan or yell may escape as air is forced past the vocal cords. Then comes the clonic phase, lasting 30 to 60 seconds, with full-body rhythmic jerking or shaking. Loss of bladder or bowel control can happen during this stage. The person has no awareness of what’s happening and won’t remember it afterward.
Focal Aware Seizures
These start in one specific brain region and stay there. The person remains fully conscious the entire time and can often talk through it. They might experience that strange stomach sensation, déjà vu, unusual movements in one hand or one side of the face, or sensory distortions. Because awareness is preserved, people can usually describe exactly what the seizure felt like after it ends.
Focal Impaired Awareness Seizures
These also start in one brain area but disrupt consciousness. The person looks dazed or confused. They may stare blankly, smack their lips, pick at their clothes, make chewing motions, or wander aimlessly. If you try to talk to them or give directions during the seizure, they won’t be able to respond normally. This can last from 30 seconds to a couple of minutes, and the person typically has little or no memory of it.
Absence Seizures
These are easy to miss entirely. The person suddenly stops what they’re doing and stares vacantly for about 10 seconds, sometimes up to 30. There may be subtle signs like eyelid fluttering, lip smacking, finger rubbing, or small hand movements, but no falling, no convulsions. It looks like a brief lapse in attention. These are most common in children and can happen dozens of times a day, sometimes going undiagnosed because teachers or parents assume the child is simply daydreaming.
What You Experience vs. What Others See
One of the most disorienting things about seizures is the gap between internal experience and external appearance. During a focal aware seizure, you might be flooded with bizarre sensory information, a sudden smell of burning rubber, an overwhelming feeling of fear, while looking perfectly normal to everyone around you. During a tonic-clonic seizure, bystanders see dramatic convulsions while you experience nothing at all: consciousness is gone, and the next thing you know, you’re waking up confused, sore, and exhausted on the ground with no idea what happened.
The memory gap after many seizures is particularly unsettling. People often rely on bystanders to piece together what occurred. The postictal confusion can make it hard to recognize familiar faces, remember your own name, or understand where you are for several minutes.
How to Help Someone Having a Seizure
If you witness a seizure with convulsions, the most important thing is to keep the person safe, not to stop the seizure. You can’t stop it, and trying to restrain someone or put anything in their mouth can cause injury.
- Stay with them and stay calm.
- Ease them to the ground if they’re falling, and clear hard or sharp objects away.
- Turn them gently onto their side with their mouth pointing toward the ground to keep the airway clear.
- Put something soft under their head, like a folded jacket.
- Remove glasses and loosen anything tight around the neck.
- Time the seizure. If it lasts longer than 5 minutes, call 911.
- After it ends, help them sit somewhere safe and talk to them calmly as they recover. They will likely be confused and disoriented.
Check for a medical bracelet, which may list their condition, medications, and emergency contacts. For seizures without convulsions, like focal impaired awareness seizures, gently guide the person away from hazards (traffic, stairs, sharp objects) and stay with them until they’re fully alert again.