Thinking and memory

Introduction
In this series of articles we examine the causes, effects and treatments for problems in thinking, memory, mood and behaviour that can occur in people who have had seizures. The aim of each article is to provide information about these symptoms as well as some useful practical tips to help overcome the problems that they can cause in day-to-day life.

Problems in thinking and memory
Have you ever been talking to someone and found yourself unable to recall a phrase or word despite knowing exactly what you wanted to say? Do have trouble planning your day efficiently? Have you found that you can remember what you did a year ago with complete clarity, yet cannot recall what you did with car keys 5 minutes ago? These and other problems in “cognitive functioning” (the collective term for the processes of recognising, interpreting, storing and retrieving information) are very common in people who have had seizures. In this article, we explore how cognitive abilities work under normal circumstances and explain how seizures, treatment and emotional states can affect their function.

How do we think and remember?
Science has shown that brain functions, such as perception, language and memory are distributed in different parts of the brain. These areas communicate with each other in order to perform complicated operations such as thinking, talking, and remembering. For example, seemingly simple acts like committing a person’s name to memory and then recalling it later involves complex series of brain processes including attention, perceptual organisation, short-term memory, long-term memory, search, retrieval and speech. These processes occur in split second waves of electrical and chemical activity that can involve structures right across the entire brain.

Complex processes such as thinking and remembering occur primarily in the cortex. This is the outer covering of cells in the brain, a bit like the bark of a tree, consisting of billions of nerve cells that make up grey matter. The interior of the brain, known as white matter, consists of nerve fibres that connect grey matter areas in order for them to communicate with each other. To give an example, the brain area responsible for creating speech is located in the front part of the brain (frontal lobe) whereas the area involved in understanding speech is located about half-way to the back of the brain (temporal lobe) connected by a thick white matter fibre pathway. This arrangement allows these areas to work independently and communicate with each other.

How do seizures affect thinking and memory?
Seizures affect brain functions by disrupting the work of brain areas that control specific brain functions, or they can affect communication between these areas. The severity of the impairment will vary depending on the type of seizures and the part of the brain where the seizure begins. For example, seizures that start in the frontal part of the brain can affect the ability concentrate, speak or solve complex problems. In contrast, seizures that occur in the temporal parts of the brain often affect memory functions such as the ability to remember names or daily events. Seizures that start in multiple places will affect a number of functions simultaneously.

Problems such as these can be present before, during and between seizures and their effects on brain function can be both long and short term. For example, short-term effects may include memory loss for the time leading up to and immediately after a seizure, whereas longer-term effects between seizures could manifest in reduced capacity to plan, name people or objects, or remember events, dates or conversations. These problems can also be compounded by frustration, anxiety and depression.

Diagnosing problems in thinking and memory
If you are experiencing a problem in cognitive function your doctor can refer you to a neuropsychologist. Neuropsychologists specialise in assessing disorders that result from disease or damage to the brain. In a typical assessment, the neuropsychologist will ask you to perform a range of tasks that test all of the major brain functions in order to find the exact source of a particular problem. Once identified, practical strategies can be put in place to help overcome the problem so as to minimise its impact on everyday life. Neuropsychologists can assist in helping to achieve better performance at school or university and/or vocational placement or workplace assistance issues.

Treatment
Treatment for seizures can vary from no intervention to antiepileptic medication and also surgery. Each of these entails inherent risks and benefits for cognitive functioning.

Some people may opt, with or without the agreement of their doctor, to not take medication for seizures. Often, people feel that they can think more clearly or remember better when not on medication. While it is certainly true that antiepileptic medications can reduce the efficiency of cognitive function, in the long term, repeated seizures can cause significant damage to the brain; this is one reason why your doctor will try to reduce medication to the minimum level required in order to prevent seizures with the fewest side effects. Indeed, good seizure control can lead to long-term improvements in cognitive functioning.

Surgical intervention can have both positive and negative consequences for cognitive function with some functions becoming less efficient, particularly around the site of the surgery, while other functions improve dramatically. Most people who have surgery notice an immediate improvement in some abilities, with more gradual improvements over the following weeks and months whilst some may remain unchanged.

Practical strategies
Strategies for assisting people to overcome cognitive problems are most effective when tailored to the individuals. However, a few practical strategies may help.

Problems in concentration

• Focus on a problem for short periods but come back to it regularly rather than try to maintain concentration over long periods.
• Keep a pad or notebook handy and write things down as you go. Revisit notes frequently.
• Try to use the early part of the day for ‘attention demanding’ activities.
• Try to reduce stress, as this can adversely affect concentration.

Problems in language

• Ask people to speak slowly or write down complex information
• Try to use external means of communication like email as a means of communication and remembering.
• Use a personal Dictaphone for recording meetings, university lectures or school classes.

Problems in memory

• Rehearse new information by writing it down, repeating information to yourself.
• Ask others for reminders, or remind yourself by writing notes.
• Use external memory aids such as notes, diaries, personal organisers, watch alarms and whiteboards.
• Try to reduce stress by exercise, hobbies, taking regular ‘time outs’, and/or reducing workload.

Problems in planning or organising

• Structure your day so that you are not doing too much all at once
• Break tasks into simple steps (written down) and work your way through them
• Take time to consolidate/take stock, before moving to a new task

About the Author:
Dr Simon Collinson is Senior Neuropsychologist at the Alfred Hospital Prahran and in private practice at The Memory Centre, East Melbourne.