A simple partial seizure results from changes in activity on one side of the brain. It does not affect a person’s consciousness or awareness. The person remains alert and awake during the seizure.

If a partial seizure affects consciousness, it is a complex partial seizure. If changes in nerve activity affect more than one part of the brain, it is a generalized seizure.

Doctors may also refer to simple partial seizures as focal aware seizures or simple focal seizures.

If a person experiences repeated simple partial seizures, a doctor may diagnose epilepsy, which involves recurring seizures.

Partial seizures are the most common type of seizures in individuals with epilepsy, and 6–12% of people with epilepsy experience this type. Complex partial seizures, in which a person loses consciousness, are more common among those with epilepsy.

In this article, find out what simple partial seizures are, how they compare with other seizures, what causes them, and what treatment options are available.

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A seizure occurs when a person experiences a disturbance in their brain’s usual activity. The brain communicates via electric signals. Disruption to these signals can result in a seizure.

Simple partial seizures happen when people have an electrical change in a specific part of their brain that affects these signals.

Doctors do not know what causes many types of simple partial seizure disorders, but genetic factors may play a role.

Other possible causes include:

  • traumatic brain injury, if a scar tissue disturbs electrical signals in the brain
  • changes following surgery
  • stroke
  • a brain tumor
  • developmental challenges
  • the use of some medications
  • exposure to toxins
  • endocrine disorders, which affect hormone levels
  • meningitis
  • focal encephalitis
  • problems with blood vessels
  • trauma to the brain involving low levels of oxygen, which may happen during delivery

Some people experience a seizure after exposure to specific triggers, such as:

Some people with diabetes may experience a type of continuous simple partial seizures called epilepsia partialis continua (EPC) if their blood sugar rises too much. Reducing blood sugar levels can help treat it.

Some infections, structural damage to the brain, and other conditions can also cause EPC.

Doctors divide seizures into groups depending on:

  • which part of the brain the changes affect
  • whether the seizures affect consciousness
  • the changes that occur — for example, whether they affect movement

Experts subdivide simple focal seizures into four main subtypes:

  • Focal motor seizures: These happen when changes affect the part of the brain that controls movement.
  • Focus sensory seizures: These occur when changes affect the part of the brain that controls the senses, such as sight, hearing, smell, and taste.
  • Autonomic seizures: These result from changes in the area that controls the autonomic nervous system. This system is responsible for breathing, digestion, the cardiovascular system, and other automatic functions.
  • Psychological seizures: These can affect people who have previously experienced psychological trauma.

Some symptoms are common in people experiencing any type of partial focal seizure, while others are specific to different types.

Some general symptoms of focal seizures that can occur alone or in combination include:

  • smacking the lips or appearing to chew something
  • picking at clothes
  • repeatedly picking things up
  • suddenly going floppy
  • experiencing jerking movements of the limbs or body
  • making side-to-side head movements
  • making a sound like a loud cry or scream
  • making repetitive movements, such as kicking or cycling
  • experiencing changes in taste, smell, vision, or hearing
  • having a feeling of déjà vu
  • experiencing sudden and intense emotions, such as joy or fear
  • having a feeling resembling a wave going through the head, known as an aura
  • experiencing numbness and tingling
  • feeling like a body part is bigger or smaller than it really is
  • seeing flashing lights
  • hearing or seeing things that are not there

In some people, a simple partial seizure is a warning seizure that can indicate that another seizure is about to occur. It can be a warning of a generalized seizure, which affects the whole of the brain and causes a person to lose consciousness.

After a seizure, an individual may continue to feel confused or have difficulty thinking clearly for some time.

A seizure that lasts longer than 5 minutes is a medical emergency, and someone should call 911.

Focal motor seizures

A person experiencing a focal motor seizure will lose control over muscle activity, usually in their arm, face, foot, or another part of their body.

Due to the way motor nerves cross the brain, if a person loses control over the right side of their brain, this will cause problems on the left side of their body, and the other way around.

The person may show:

  • jerking muscle contractions or other movements, especially in the face, hands, and toes
  • turning movements in the head and neck to the opposite side
  • a contraction of the limbs on one side
  • in a clonic seizure, twitching or jerking in specific muscle groups every 1–2 seconds or more in a seizure lasting up to 2 minutes
  • in a tonic seizure, contractions lasting longer than 5–10 seconds and involving the limbs and the whole body
  • in a versive seizure, forceful movements of the head and eyes toward one side

Focus sensory seizures

This can cause tingling sensations and changes in hearing, vision, smell, and taste. A seizure focused on the right side of the brain can cause sensations on the left side of the body.

Symptoms include:

  • numbness
  • tingling
  • a crawling sensation
  • seeing, hearing, smelling, or tasting something that is not there

Autonomic seizures

Autonomic seizures affect parts of the brain that deal with the bodily functions a person does not control with their awareness.

Autonomic seizures can affect:

  • heart rhythm and blood pressure
  • bowel activity, which could lead to nausea
  • pupil size
  • regulation of body temperature, resulting in sweating and shivering

Psychic, or nonepileptic, seizures

A psychic seizure causes an individual to experience:

  • sudden emotional changes, such as feelings of fear or anxiety
  • déjà vu
  • memory flashbacks
  • dream-like events
  • agitations
  • uncontrolled outbursts of laughing or crying

Learn more about nonepileptic seizures here.

For recurring seizures, doctors usually prescribe anti-convulsants as the first line of treatment.

If a seizure happens because of an infection, high blood sugar, or a tumor, for example, the doctor will treat the underlying cause.


A range of medications known as anti-seizure drugs (ASDs) aim to help manage seizures. Each drug works differently, and sometimes a doctor will prescribe a combination.

The doctor will prescribe an ASD suitable for a person’s age and the severity of their symptoms.

Medication options for seizures include:

If a person takes ASDs, they must not suddenly stop taking them without first consulting a doctor. To prevent a seizure, the body needs to contain a certain amount of anti-convulsant medications. Stopping suddenly can trigger a seizure.

Learn whether natural treatments can help manage epilepsy here.

Other options include the following:


A ketogenic diet may help manage seizures in some people whose epilepsy has not responded to medication. In this diet, less than 10% of the energy provided by food comes from carbohydrates. The diet focuses heavily on protein.

According to a 2019 review, recent studies indicate there may be a link between epilepsy and the gut microbiome. The review authors propose using the ketogenic diet in such a way that it boosts the production of specific microorganisms. This, they say, could offer protection to the nervous system, potentially helping manage epilepsy.

However, they note that a lot of research is still necessary for this to become a treatment option. The diet may not be suitable for everyone. People should seek guidance from a doctor about whether adopting this diet is a good idea and how to implement it.

Learn more about keto diet and managing epilepsy here.


For people whose seizures do not respond to medication, surgery may be an option. This involves removing an area of the brain responsible for seizures, such as scar tissue, a tumor, or other elements.

However, depending on the site of the surgery, a person may experience other problems afterward, such as difficulties with verbal memory, difficulty naming things, and other neurological changes.

Other possible complications include:

Surgery is usually only suitable when other options have not helped. It may only be possible where the cause of the seizures is easily accessible.

Vagus nerve stimulator

Some people benefit from a device called a vagus nerve stimulator (VNS).

A VNS is a small unit that surgeons place under the skin in the chest and attach to the vagus nerve in the neck. That vagus nerve runs up to the brain, and the electrical signals released from the VNS change the electrical activity in the brain that causes seizures. A VNS can help reduce the frequency, length, and severity of seizures.

Most people undergo implantation in day surgery under local anesthesia. However, there is a risk of complications, such as a slowing of heart rhythm, changes in breathing patterns, and damage to the vocal cords.

Experts are currently investigating a newer device, the transcutaneous VNS (tVNS). It is a noninvasive technique that applies electrical currents through electrodes on the surface of the skin.

tVNS is cheaper, and there is a lower risk of complications. Studies into ways of using this device to treat epilepsy and other conditions are underway.

Learn about CBD oil for seizures here.

If a person experiences any symptoms that may indicate a simple partial seizure, they should seek medical attention immediately.

Sometimes, others may misinterpret a simple partial seizure as not paying attention. This can be challenging for children in school. Having a correct diagnosis can help a person get the right treatment to manage seizures.

A doctor will:

If a person has repeated seizures, the doctor may diagnose epilepsy.

A person who has partial seizures is more likely to experience a recurrence than someone who has generalized seizures. However, recurrence rates for simple and complex partial seizures are about the same.

The risk of complications from a simple partial seizure is low. For instance, a person is less likely to accidentally breathe in food while conscious during a seizure. However, there is a risk of falls and injury, and long-term nerve damage can occur if a person does not receive treatment.

Seizures can affect people with epilepsy and a range of other conditions. If a person has recurring seizures, a doctor may diagnose epilepsy.

There are different types of seizure. A partial seizure starts when changes occur in a specific part of the brain, while a generalized seizure involves the entire brain. In a simple partial seizure, the person will not lose consciousness.

The symptoms of a simple partial seizure vary depending on the subtype and other factors. While complications are less likely to occur during a seizure where a person is conscious, it is still important to seek treatment, as this can prevent long-term problems.

If an underlying health condition is causing the seizure, a doctor can provide appropriate treatment.