The brain contains billions of nerve cells — called neurons — that communicate with one another by sending and receiving electrical signals. A seizure occurs when large groups of neurons fire at the same time and produce an “electrical storm” that interrupts normal brain function. This sudden, temporary interruption in brain activity causes changes in behavior, sensation, movements, or awareness.

Brain damage is an injury to brain tissue that affects a person’s physical, emotional, or behavioral health and is caused by a head injury, an illness, or a condition. Typically, an isolated seizure does not lead to lasting brain damage but sometimes has a negative effect on brain function. However, a person with uncontrolled epilepsy or rare types of seizures may be at greater risk of brain damage.

Isolated vs. Repeated Seizures

A seizure is defined as a single event that a person experiences just once or very rarely. Often called isolated seizures, these events can result from low blood sugar, alcohol misuse, high fever, infection, brain tumors, or medications, among other triggers. Isolated seizures typically do not call for specific treatment other than managing the underlying medical problem.

On the other hand, repeated or recurring seizures are defined as two or more seizures that occur within a short period. Known as epilepsy, repeated seizures require medical treatment to manage and control symptoms.

What Causes Brain Damage?

Brain damage occurs when neurons and their connections are destroyed. It is thought that isolated seizures have a negative impact on the brain. However, researchers in neurology believe that whether a seizure can cause long-term brain damage depends on several factors, including the type, number, and cause of the seizures. How well your epilepsy responds to available treatments also plays a role. Some seizures listed below are known to cause negative long-term effects on brain function.

Refractory (Uncontrolled) Seizures

Epilepsy is difficult to treat, and not every person responds well to antiepileptic drugs. Some people become drug-resistant and continue to have seizures even while taking these medications, a condition that is known as refractory (uncontrolled) epilepsy. In the United States, about 56 percent of adults with epilepsy have uncontrolled epilepsy, according to the Centers for Disease Control and Prevention (CDC). In addition, people with uncontrolled seizures are up to 10 times more likely to have sudden unexplained death in epilepsy.

Uncontrolled epilepsy can also be caused by a misdiagnosis, improperly prescribed or used medications, or lifestyle factors such as a poor diet, high stress, and lack of sleep. If uncontrolled epilepsy doesn’t improve, it can cause brain damage and negatively affect a person’s quality of life.

Status Epilepticus

A seizure typically lasts from 30 seconds to two minutes. However, sometimes a seizure is followed by another or the seizures don’t stop, so the person can’t fully recover between the seizures and may remain unconscious. When a seizure lasts longer than five minutes or a person experiences recurrent seizures without recovery in between, this is called status epilepticus. During status epilepticus, neurons are destroyed and cause permanent brain injury.

Although status epilepticus is rare, it can occur with any type of epilepsy or seizure. Status epilepticus is a medical emergency that may lead to permanent brain damage or death. One study found that people who survive status epilepticus have significant changes in their behavior, learning, and memory. The researchers reported that this result seemed to especially affect children whose brains were still developing.

Temporal Lobe Epilepsy

For people with temporal lobe epilepsy, seizures can last longer than those of others and are often more challenging to treat. Studies have found that prolonged complex partial seizures in temporal lobe epilepsy that also progress to tonic-clonic seizures (“tonic-clonic” refers to the seizures’ two phases) may lead to declines in cognitive (thinking, reasoning, and memory) function and brain damage. Additionally, severe temporal lobe epilepsy that doesn’t respond to medication sometimes is treated with surgery, which can complicate the overall picture in terms of long-term brain damage.

Seizures in Children

The brain grows and develops from birth throughout adulthood, with the most critical period of development occurring during the first eight years. Infants and children with epilepsy are at much higher risk of experiencing challenges in their development of cognitive, motor (muscular movement), and psychiatric (mental, emotional, and behavioral) functions. They are also at greater risk of status epilepticus and sudden unexplained death in epilepsy. That’s why, if your infant or child is experiencing seizures, it’s critical to seek care by a doctor right away.

Severe seizures in an “immature brain” can bring about changes in various brain structures and kill neurons, thus causing brain abnormalities, according to animal study findings that researchers apply to human children. Some changes are irreversible and cause permanent brain damage, but some children are able to recover. In addition, infants who experience seizures during their first few weeks of life (also known as infantile spasms) are at a higher risk of lifelong seizure activity and developmental problems, as well as related death.

Consequences of Brain Damage

The consequences of uncontrolled epilepsy, prolonged seizures, and recurrent seizures go beyond the injuries or accidents that may occur during the seizure. One risk factor involves damage to neurons, which can lead to brain damage. Examples of brain damage include:

• Impairment of cognitive processes such as memory and language
• Difficulties with school and learning
• Difficulties with social interactions
• Psychiatric symptoms such as depression or anxiety
• Postictal (post-seizure) psychosis such as disordered thinking, hallucinations, and symptoms related to schizophrenia or bipolar disorder
• Changes in personality
• Difficulty with balance and coordination
• Repeated severe seizures
• Problems with vision
• Sudden unexpected death in people with poorly controlled seizures

Additionally, a person’s disease course in epilepsy may begin with focal seizures — affecting just one part of the brain — and later progress to generalized (grand mal) seizures that affect multiple parts or the entire brain. This can make it challenging to get a proper diagnosis and affect possible long-term effects on brain function.

Although all these consequences sound scary, it’s important to know that every person’s seizure course is different, and outcomes vary widely among people living with epilepsy. For some, multiple seizures lead to very few long-term effects, while others experience serious issues of brain damage.

Treatment Options

There is currently no treatment or cure for brain injury or brain cell death, but researchers in health care are studying ways to regenerate cells in the brain using stem cell therapy. This approach holds promise as a potential alternative therapy for people with epilepsy.

If you experience epilepsy, the most important way to avoid brain damage is to address the underlying cause of the seizure (if known) and achieve seizure control. This involves following a proper treatment plan and adopting a healthy lifestyle to reduce the risk of worsening symptoms and triggering seizures, as well as to avoid injuries that could lead to disability or brain damage. If anti-seizure medications don’t help to control your seizures, be sure to read about other treatment options for epilepsy. Prevention of uncontrolled seizures should be the No. 1 priority to reduce the risk of permanent brain damage.

Talk With Others Who Understand

MyEpilepsyTeam is the social network for people with epilepsy and their loved ones. On MyEpilepsyTeam, more than 110,000 members come together to ask questions, give advice, and share their stories with others who understand life with epilepsy.

Do you have or suspect you have brain damage caused by seizures? Are you taking steps to avoid triggering seizures that could lead to brain injury? Share your experience in the comments below, or start a conversation by posting on your Activities page.