What Causes Seizures? Understanding Triggers, Brain Activity, and Risk Factors
Seizures happen when the brain’s usual electrical activity is suddenly disrupted. The brain uses organized electrical signals to manage movement, awareness, sensation, and behavior. If these signals become abnormal or out of sync.
The Epilepsy Foundation reports that about 1 in 10 people will have a seizure at some point, and around 1 in 26 will develop epilepsy, which means having repeated, unprovoked seizures. Learning about what causes seizures can help reduce uncertainty, spot triggers, and guide treatment.
How Seizures Affect the Brain
The brain has billions of nerve cells, called neurons, that communicate through electrical and chemical signals. A seizure happens when a sudden burst of abnormal electrical activity briefly interrupts normal brain function.
Depending on where the seizure begins and how it spreads, symptoms may include:
Staring spells or loss of awareness
Sudden confusion
Uncontrolled movements
Muscle stiffness or jerking
Sensory changes, such as unusual smells or sensations
Loss of consciousness
Some seizures last just a few seconds, while others can go on for several minutes.
Common Medical Causes of Seizures
There are many reasons why seizures can happen. Sometimes, a specific medical event triggers a seizure, while in other cases, seizures are part of epilepsy.
Common causes include:
Epilepsy, a neurological disorder causing recurrent seizures
Head injury or concussion, which can disrupt brain signaling
Stroke is one of the most common causes of seizures in adults over 60.
Brain infections, such as meningitis or encephalitis
Brain tumors or structural abnormalities
Genetic factors, which may increase susceptibility
Developmental or neurological conditions
According to the CDC, stroke, traumatic brain injury, and infections are among the leading causes of acquired epilepsy.
Common Seizure Triggers
A seizure trigger is anything that makes a seizure more likely in someone who is already at risk. Not everyone has clear triggers, but finding them can help lower how often seizures happen.
Common seizure triggers include:
Sleep deprivation
Stress or emotional strain
Illness or fever
Missed seizure medications
Hormonal changes
Alcohol use or withdrawal
Dehydration
Physical exhaustion
The Epilepsy Foundation identifies sleep deprivation and stress as two of the most commonly reported seizure triggers.
Seizure Risk Factors
Some factors can make it more likely for a person to have seizures or develop epilepsy. These risk factors can affect how the brain is built, how it works, or its electrical balance.
Risk factors include:
Prior brain injury or concussion
Stroke or vascular disease
Brain infections
Family history of epilepsy
Neurological disorders
Developmental conditions
Sleep disorders
Having risk factors does not mean you will definitely have seizures, but it does show why getting a proper neurological checkup is important if symptoms appear.
Why Proper Evaluation Matters
Finding out what causes seizures helps doctors choose the right treatment and improve long-term results. A neurological evaluation may include:
A detailed medical history
Neurological examination
EEG (electroencephalogram) to measure brain activity
Brain imaging, such as MRI
These tests help neurologists see how the brain is working and decide on the best treatment plan.
Many people are able to control their seizures well once the cause is found and treatment is adjusted.
Moving Forward with Knowledge and Support
Having a seizure can be sudden and worrying, but learning the cause is a key step toward understanding and control. New advances in neurological care make accurate diagnosis, effective treatment, and a better quality of life possible.
With the right evaluation and support, many people with seizures can manage their condition and enjoy full, active lives. If you or someone you know has had a seizure or unexplained neurological symptoms, seeing a neurologist can help find the cause and guide the next steps in care. Contact us to make an appointment.
