Are you concerned about changes you see in yourself? Changes in your ability to remember names, word meanings, even shopping items? Changes in how you go about making plans? Changes that affect the way you live your life, and not always for the better?

For most people—especially those who don't have very many seizures—epilepsy does not cause any serious problems with their thinking. If you have mostly primary generalized seizures, like absence, myoclonic, or tonic-clonic (grand mal) seizures, you are much less likely to have problems with your thinking than someone who has partial-onset seizures (seizures that begin in one area of the brain, often the temporal lobe). Some people with epilepsy of this kind do experience problems with their memory, language, or other kinds of thinking.

Whether you've had one or many seizures, you probably want to know how seizures affect the way you think. Does each seizure permanently change the way your brain works? Will seizures that last over 5 minutes stop you from learning new things? The answers can't be found easily, and may not be the same for every person.

How do we think?

First of all, let's talk about what goes into the way you think. To go about your daily life, many different abilities, or functions, come together. Three of these functions are memory, language, and what we call "executive function." Executive function really includes many different things, such as planning, reasoning, and stopping unwanted behavior.

The brain is organized so that one area is in charge of each task. Each area has developed over time to become very good at performing it. But because these tasks are so important, human brains developed so that different areas of the brain can work together. Communication lines formed between different areas so the brain would have a well-developed backup system.

An excellent place to find diagrams and information about the brain is at the website Neuroscience for Kids—http://faculty.washington.edu/chudler/neurok.html—good for all ages!

How do seizures change thinking?

When seizures happen, they can have two different effects on thinking:

• A seizure can disrupt the area of the brain in charge of a particular function. So if seizures happen in the area in charge of language, you may not be able to name an object when you see it.
• Seizures can also stop the communication between different areas. The lines are cut, so to speak. Even though you may know the name of an object, the part of the brain that knows can't tell the rest of your brain. The name is lost.

One thing to remember is that where seizures start tells what function may be affected. If seizures start in several areas, or are generalized, they may affect many different functions.

Now you probably want to know what area does what, and how seizures in each area affect functioning.

Memory

Buried deep inside the temporal lobe is the hippocampus (hip-o-CAM-pus). This strange-looking thing is responsible for receiving new information and storing it. However, it only stores information for a short time. Then, if the information seems important, it ships it to a different section of the brain for long-term storage. Once the information is needed again, the hippocampus helps retrieve it. The hippocampus is the ultimate librarian.

The amygdala (a-MIG-dah-lah) is also very important to memory. This structure is responsible for basic emotions, such as fear, anger, and sexual attraction. When a person, place, or thing causes an emotional reaction, the amygdala attaches the emotion to the memory.

How do seizures affect memory?

Seizures, especially ones that start in the temporal lobe, can cause a major blow to the hippocampus. The hippocampus is very sensitive to changes in brain activity. If seizures starting here go untreated, the hippocampus starts to harden and shrink. Then it is as if the librarian has gone on strike. Information may be stored, but in a disorganized way. No one is there to find what you need. You may find what you need after a great deal of searching, or you may not find it at all. Luckily, there is one hippocampus on each side of the brain. So if one is affected by seizures, the other can help pick up the slack.

Language

Different sites are in charge of speaking, understanding, and storing words. For speaking, Broca's area takes the lead role. Broca's area is located just above the front of the temporal lobe. It is the center for outgoing words. It receives information from the many parts of the brain where words are stored. It then sends this information to the part of the brain that controls your mouth.

To understand words that you hear or read, Wernicke's area steps in. Wernicke's area is on the top part of the temporal lobe, toward the back. It is the center for incoming words. When you hear and understand words, phrases, and sentences, it is because Wernicke's area has done its job. Words are stored in many different places throughout the brain. New research is finding that names and words may be stored by categories. For example, the names of animals are stored toward the front of the temporal lobe. Tools are stored farther back. Faces are stored at the bottom back section of the temporal lobe. Names of people that are close to you are stored at the very front of the temporal lobe, called the temporal pole.

How do seizures affect language?

Seizures can affect language in different ways. First of all, most people have the main part of their language functions on the left side of their brain. So if your seizures start on the right side of your brain, your language may not be affected at all.

But even if your seizures start on the left side of your brain, hope is not lost. Seizures, by themselves, do not stop people from speaking or understanding words. Even if seizures happen every day for most of your life, you are still able to read, speak, and understand words. The main language problem caused by seizures is with finding words. Many people cannot think of the name of something, even when it is right in front of them. This is because seizures can damage the area where the word is stored, as well as the communication lines that carry or transport the word.

Executive function

The largest part of our brain is the part that handles executive function: the frontal lobe. This goes from the front tip of the brain to about halfway back (just in front of your ears). When you make a list, plan a driving route, or organize your thoughts, it is thanks to the frontal lobe. The frontal lobe has a major role in decision making. It helps you go through the pluses and minuses logically.

The frontal lobe has the final say in your social behavior. It regulates how you interact with other people. Some people claim this is where your personality comes from. It manages how you talk to other people.

The frontal lobe also helps you to stop unwanted behavior. For example, say something happens that makes you feel like laughing or yelling but you know it is not the right time or place to laugh or yell. Your frontal lobe tells you that you shouldn't do it. It also helps you to not laugh or yell.

How do seizures affect executive function?

Seizures that happen in the frontal lobe can cause your planning ability to become weaker. You may not be able to organize your thoughts or your actions in the best way. If you are making a shopping list, for instance, you may think or write the same item over and over.

It may be harder for you to interact with people. Your attention may drift much sooner than before. Some people say their personality has changed after having seizures for many years. It also may be harder for you to stop unwanted behavior. You may say what's on your mind even when it's not the right time. For example, it is probably not a good idea to say that you hate your boss when you're in the middle of your annual performance review, unless you're willing to deal with the boss's reaction.

What else I should know?

Seizures affect thinking in different ways for everyone. Even if you have seizures that start near your hippocampus, your memory may not become extremely bad. Many different things need to be considered, such as:

• How long you've had seizures
• How long each seizure lasts
• What you are naturally good and bad at
• The effects of your medications

Talk with your doctor if you are concerned about changes in your memory, language, or executive function. To get more information on these topics, check out other articles on this website.

Topic Editor:Steven C. Schachter, M.D.
Last Reviewed:1/2/07