Focal seizures: everything you need to know

Focal seizures are the most common type of seizure - about 60% of people with epilepsy have them. However, the term ‘focal seizure’ covers a wide variety of symptoms - one person’s focal seizure might involve conscious feelings of anxiety, while another person may lose consciousness. 

So, what are the different types of focal seizure and why do they cause such different symptoms? 

What is a focal seizure?

A focal seizure is any kind of epileptic seizure that is ‘focused’ on one part of the brain and (usually) does not spread from there. They are different to generalized seizures, where unusual electrical activity happens all over the brain at the same time (for more detail, read about the difference between generalized and focal seizures). 

Focal seizure symptoms can be very different depending on which part of the brain the seizure happens in. 

3 types of focal seizure

There are 3 types of focal seizure:

1. Focal aware seizure

This is when you have a seizure but remain conscious (aware of the world around you). They normally last less than a minute.

2. Focal impaired awareness seizure

If you have focal impaired awareness seizures, you usually lose consciousness, although you might look like you are still awake. They normally last between one and two minutes. 

3. Secondary generalized seizures

This is when the seizure starts in one part of the brain, but then spreads to the rest of the brain and causes a generalized seizure

Most focal seizures are relatively short. Sometimes people can go back to what they were doing before the seizure right away, but for others they may feel tired and confused for a few minutes or even hours. 

Focal seizure symptoms and location in your brain

Depending on where in your brain the seizure begins, you might experience very different focal seizure symptoms. 

• Frontal lobes: a focal seizure beginning in this part of the brain may cause twitching, unusual body movements, shouting, laughing or moving your head to the side
• Occipital lobes: if the focal seizure happens here, you may see flashing lights, colors, or notice your eyes moving in unusual ways
• Parietal lobes: you may experience numbness and other strange sensations in your body
• Temporal lobes: can cause different emotions, such as fear, deja vu, unpleasant tastes/smells and uncontrollable behaviors (such as fidgeting or running)

Diagnosis and focal seizure treatment

If you believe you are experiencing focal seizures, it is important to visit a neurologist or epilepsy doctor who can do tests to find out what is happening. If possible, bring along a video recording of your seizures. To diagnose this kind of epilepsy, doctors may:

• Use an EEG machine which checks for unusual electrical activity in your brain
• Use an MRI scanner which can ‘see’ inside your brain and discover if there is a specific cause of the seizures, such as damage or a lesion
• Conduct a medical history to learn more about past illnesses or head injuries that may be focal seizure causes

If your doctor diagnoses you with epilepsy, they will work with you to create a strategy for your focal seizure treatment. It might include: 

• Taking anti-epilepsy drugs
• Using a medical device that helps control seizures
• Brain surgery
• Other treatment pathways

Learning about your focal seizures can help you understand your epilepsy better and feel more confident about managing it. To learn more, read our blog about what happens in your brain during seizures.