Epilepsy and memory

Epilepsy and memory

Living with epilepsy and memory problems

Throughout our lives memories are being made, sorted, stored and found by our brain. Links made between our brain cells help us to remember the thoughts, skills, experiences and knowledge that make each of us unique.
This page gives a brief introduction to memory and looks at some of the issues around epilepsy and memory.

How does memory work?

Memory is the brain’s ability to store information and then find it again later. Chemical and electrical changes happen in the brain when new memories are made. 

When you try to remember something for the first time, there are usually three stages you go through: learning the information, storing it, then finding the information again.

Your memory might be affected if any of these stages are disrupted, for example by a break in concentration.  

Learning

This happens when you want to learn something new, such as a friend’s new address. It may involve repeating the address several times or linking it to an existing memory. For example, linking the new address – 1 Albert Square – to the memory of the television show Eastenders.

Storing

This is when the information learnt is stored permanently in the brain.

Recalling (finding the information)

This is the brain’s way of finding (recalling) the information that has been learnt. For example remembering your friend’s new address when sending her a letter.

Types of memory

There are two main types of memory:
short-term memory and long-term memory.

Long-term memory

This is information stored over a long time. 
There are many types of long-term memory:

• Semantic memory
  Semantic memories are knowledge and facts about people, places and things.
  An example of a semantic memory would be recalling that a banana is a yellow fruit, or that Edinburgh is the capital of Scotland.
• Episodic memory
  Episodic memories are when we remember events or episodes in our lives, such as past conversations, holidays or recalling your first day at school. Episodic memories are personal, and so are different for everyone.
• Prospective memory
  This relates to doing things in the future, such as remembering a doctor’s appointment for next week or remembering to send a card in time for a friend’s birthday.

• Procedural memory
  This is our memory of skills and how to do a certain job or task. Examples are knowing how to ride a bike, play the piano or how to tie a shoelace. These tasks often require effort to learn but once learnt are rarely forgotten.
  This is one type of memory that is often unaffected.

Short-term memory

This is sometimes called working memory or attention span. This is the amount of information you can keep in your mind at any one time. Most people can usually keep about seven to nine letters, words or numbers in their mind at once. This will be forgotten in minutes unless they try to commit this information to memory. 

With short-term memory, information is only kept for the length of time you need to use it.  An example of your short-term memory working is remembering a telephone number while you dial. Because you only need this type of information for a short time your brain doesn’t store it.

How epilepsy can affect memory

It is not unusual for people who have epilepsy to have problems with their memory.  If you have epilepsy, you may experience problems with your memory for any or all of the following reasons. 

Seizures

Any type of epileptic seizure could potentially affect your memory, either during or after a seizure.

If you have lots of seizures then memory problems might happen more often.

Some people have seizures that affect all of the brain at once: these are called generalised seizures. Others have partial seizures, affecting only part of the brain.Some people have both generalised and partial seizures. Memory problems can happen for all seizure types.

•  More about seizures

If you have partial seizures, the way your seizures can affect your memory will depend on where in the brain your seizures happen. The brain has two halves (hemispheres).

Each half has four parts called lobes. They are the occipital, parietal, temporal and frontal lobes. Abnormalities in the temporal and frontal lobes of the brain are the most common reason for memory problems.

The left temporal lobe is important for verbal memories such as learning people’s names and remembering information for exams. If you have seizures that start in this area you may have problems remembering words, and get stuck in mid-conversation as you cannot think of the right word.

The right temporal lobe is important for visual memories like remembering a person’s face or finding your way around a new place.

If you have seizures in your frontal lobe you may have problems remembering to do things in the future, because this part of the brain is important for prospective (or future) memory.

After a seizure

You may find that straight after a seizure you have difficulty remembering information. This is sometimes called post-ictal (after-seizure) confusion and it usually goes away once you have had time to recover. The length of time it takes for memory to return to normal can vary from person to person. Even after fully recovering from a seizure you may find that your memory is permanently affected.

Anti-epileptic drugs (AEDs)

Memory difficulties can sometimes happen due to the side effects of taking AEDs, such as drowsiness or attention problems. These side effects can affect short-term memory, and may make it more difficult to learn and store new information.

There may be a higher chance of you having memory difficulties if you take high doses of medication or more than one type of AED. However, taking AEDs may help to improve memory by making seizures less frequent or by stopping them completely.

•  More about AEDs for adults and AEDs for children

Surgery

Some people have surgery to stop their seizures from happening. Even if surgery stops your seizures, you may have memory problems afterwards. This is most common with surgery to the temporal lobe. Memory problems are the most frequently reported complaint following surgery for epilepsy.

•  More about epilepsy surgery

Other factors that can affect memory

Mood and concentration

The way you feel can affect how well you are able to remember information. Feeling confident or happy can affect the way the brain works by increasing your ability to concentrate and take in information.

The more anxious or stressed you feel, the more likely it is that your brain will have difficulties at the ‘learning’ stage. Also, when you have trouble recalling information, worrying might make it harder to find the correct information.

Tiredness, lack of sleep or feeling unwell can also affect concentration and memory.

Age

In general we have more difficulty storing and recalling new information as we get older. This might be because of the way the brain changes physically. But also as we go through life the demands on our memory can change. 

Managing different areas of your life such as work, family, study and social life, can be complicated and may increase the chance of you forgetting things.

Managing memory problems - using memory aids and reminders

Anyone can have problems recalling information, and so memory problems are common. Keeping the brain alert and active is a good thing but on its own may not necessarily improve memory. 

It is important to know what aspects of your memory are better than others and what factors affect your memory. Try not to worry too much about your memory problems as this can often make them worse.

Memory aids may help you to cope with memory problems. Different aids or reminders may suit different types of memory problems and they work best if they are used regularly as part of a routine. Here are some ideas.

• Post-it Notes™
  Using sticky notes may help you remember to do certain things. For example sticking a note to the front door to remind you to pick up your door keys before you leave the house.
• Calenders
  Calenders can be useful especially if you keep them in places where you will see them easily and often, for example a fridge door.
• Diaries, journals and ‘to do’ lists
  Diaries can be a useful way to keep note of appointments, birthdays and phone numbers. Keeping more detailed notes in a diary or journal may be a helpful way to keep track of people you have met, where you have been and what you did.  A diary can also be a handy way of recording seizures.
  ‘To do’ lists can be a useful way to record daily tasks, for example phone calls to make, bills to pay, or remembering to put the recycling out. Diaries and ‘to do’ lists are often available as part of email and other computer software. 
  > More about NSE's seizure diary
• Drug wallets
  These remind you to take medication and how many tablets to take. They usually hold seven small containers to keep medication in, one for each day of the week. Each container is divided into sections, usually marked morning, afternoon and evening.   
  The containers can be removed if you are going out for the day and want to take your day’s medication with you. Some drug wallets also have an alarm to remind you when it is time to take your medication.
  They can also be used to check if you have already taken your medication and to avoid taking it twice by mistake.
  > More about drugs wallets
• Alarms and mobile phones
  Setting alarm clocks or using the alarm on a watch or mobile phone may be a useful reminder as part of a daily routine. For example reminding you that it’s time to take your medication or feed a pet.
  Many mobile phones also have a reminder service. With this you can write a message and then set a date and a time for the phone to send the message to you or sound an alarm. As well as for everyday tasks, it can be a useful way of remembering something that is not part of your usual routine, for example a dentist’s appointment.
• Hand-held computers
  Personal Digital Assistants (PDAs), also known as ‘palmtops’, and other hand-held devices often have memory aids. These include diaries, ‘to do’ lists, alarms and reminder messages.

• Other people
  Asking a friend or relative to remind you to do something may be helpful.

Other memory techniques

Some memory techniques can help the brain to store and find information. They often need practice and may suit some people more than others. But they can be helpful when you can’t use memory aids, such as in an exam. These techniques often use rhymes, stories or images to help you to link ideas to make a stronger memory.
Here are a few ways for you to deal with some common memory problems.

Remembering a word that’s ‘on the tip of your tongue’

If you have trouble finding a word there are ways that may help you to think of it.  One way is alphabetical searching:

• in your head go through the alphabet asking yourself if the word you’re looking for begins with ‘a’ ‘b’ ‘c’…etc.
  If this doesn’t work try the next step;
• concentrate on the letters that seem to be most likely and think about, or say out loud, the letter or combination of letters; 
  or
• if the first two steps haven’t helped, stop trying to think of the word and it may eventually come to you.

If alphabetical searching does not work, you could try using a different word. If you are talking to someone at the time, you may want to tell them that it’s not the word you were looking for. They may try to help by suggesting the right word.

Remembering someone’s name

Sometimes you don’t need to use a person’s name when speaking to them face to face. If you need to use their name and you’ve forgotten it, then simply asking them to remind you is often the quickest and easiest way to avoid embarrassment.
The following technique could help you to remember someone’s name.

• When you meet someone for the first time concentrate on their name, repeat it to yourself and use it while you talk to them.
• Imagining pictures can be helpful to try to make a name more memorable. To do this make an image of the person that 
  has something to do with their name. For example Mr Bridge sitting on a famous bridge.
• Use a rhyme, for example Joan always moans or Mr Shah drives a sports car!
• Physical features can also help you to remember names, for example you could imagine Mr Pearman as a curvy pear!

• It can be helpful to write the name down and try to think of a way to remember it later, that way you will have more time to be creative.

Remembering where you’ve put something

Concentrating while you put things away can help you to avoid losing items. Take a few seconds to make a picture in your mind of the object in the place you’re putting it. This may make it easier to recall where you put it the next time you need it.

Another technique is going over in your mind what you were doing the last time you had the missing item, this is called mental retracing. However physically going back to where you were is often more helpful.

It can also be helpful to have a filing system, a standard routine, or particular places to keep things. Hanging your keys up in the same place when you come home means you will always know where they are. Making a note in your diary of where you have hidden a birthday present may help you to find it later.

Using exam techniques as memory aids

Using mnemonics

Mnemonics are mental strategies often used to revise for exams. They include sayings or rhymes that help you recall information. First letter mnemonics use the first letter of each word in a sentence to remember the order of things. An example is learning the order of the colours of the rainbow by: Richard of York gave battle in vain, to help remember the sequence red, orange, yellow, green, blue, indigo and violet.

Using pictures or mind mapping

You may find it easier to remember pictures than words. If you can draw a picture that represents what you are reading or revising then remembering the picture may help you to recall the information. 
 A mind map, or ‘spidergram’, is when you draw a diagram or map of the information, often using a key word or phrase at the centre of the diagram.

Finding a connection 

When revising try to link what you are reading to a personal experience or something you already know. Making such a connection makes it more likely that you will recall the correct information.

Preparing for exams

If you are taking exams these ideas might help alongside other techniques or memory aids:

• revise somewhere quiet where you won’t be disturbed or distracted, to help you stay focused on what you’re doing;
• test yourself before the exam. Past papers or revision guides can help;
• try to get a good night’s sleep before the exam. The brain’s ability to recall information works better when it’s been 
  rested and is alert; and

• when the exam begins, before you start the question, you may find it helpful to quickly write or draw your revision aids on rough paper. This may help you to remember what you have been revising.

Assessing memory

The National Health Service (NHS) is able to provide memory assessments for people who are having memory problems. Memory assessments are usually done by a psychologist who can also advise on ways to manage memory difficulties.
If you think a memory assessment would be helpful for you, you can ask your GP or specialist to refer you for one.  

© The National Society for Epilepsy
Information produced in July 2009