Doctor, doctor

The symptoms of temporal lobe epilepsy can feel be extremely bizarre. Rebecca Willison describes a series of strange experiences that eventually led to her diagnosis

I can’t pin-point when it began. The feeling that things were not quite right increased steadily over a long period. This was mainly during the two or three years leading up to my diagnosis. Increasingly, I felt unsure of myself because I couldn’t formulate my thoughts. I found social and work situations difficult because background noise or interruptions confused me. I sometimes couldn’t think of what I was trying to say, or take in what was being said.

Sometimes I would feel scared for no reason, trying to work out a world that seemed more and more puzzling all the time. I began to feel disconnected from myself and from everyone and everything around me. My husband would ask what was wrong. All I could say was that I felt weird.

I began having strange episodes where I could remember things from my childhood with great clarity, along with frequent experiences of deja vu. All of this coincided with a particularly stressful period in my life. I put it all down to stress or anxiety, since my mother was terminally ill at this time. After she died, I began to think that I had developed psychic powers – that could at least partially explain the strange sensations!

At this stage, I made several visits to the GP – but my symptoms were vague and non-specific. Stress – along with the fact that I suffered from migraines – meant that any other underlying cause was not considered. But I knew something else was wrong.

We’ve been here before

Very suddenly the problem became much worse. The attacks of deja vu and memory flashbacks were happening daily. They were so convincing, I actually felt I had gone back in time. I felt powerful flashbacks of particular childhood experiences. The flash would always take the form of a still picture – I couldn’t see or hear anyone talking. Sometimes there would be a series of random pictures – of the dog I had as a child, for example.

Once, I had a memory of walking from the local shops back to my house wearing my favourite outfit. I felt like I was actually wearing those clothes. I would experience flashes of memory so vivid I actually felt like I was there. It sometimes took me a while to separate the past from the present. I would know that I was in my present, but I would almost be thinking: ‘What am I doing here now?’

These flashes of the past made my present feel like I was seeing into the future. I don’t remember feeling particular emotions relating to these events. They were usually quite mundane things – I was just there. In fact, once I realised these flashes were childhood memories, it was actually quite nice to remember my childhood so clearly.

Sometimes, I would suddenly get a taste of food in my mouth that was so strong it was almost like I was actually eating it! Usually these were foods from my childhood, too. These strange feelings were now accompanied by a rushing feeling in my stomach, similar to feeling nervous or excited. I constantly felt as though I had forgotten something. My short-term memory became very poor.

Sometimes I felt extreme fear for no logical reason. The confusion became so severe that it was very difficult to go out, my brain struggling to process so much information. One day I even visited my GP but couldn’t remember why! On the worst days I was barely able to make a cup of tea without becoming crippled by confusion. The sequence of tasks involved completely bewildered me.

When the word ‘epilepsy’ was first mentioned, I thought they must have mixed my notes up with another patient’s. I wasn’t collapsing on the floor and I hadn’t noticed any photosensitivity. I was a 31-year-old woman – why on earth would I suddenly develop epilepsy?

Since then I have learned a lot about the condition and have realised how many misconceptions surround it. Like most people without experience of epilepsy, I had no idea there were different types. People make so many assumptions about what it means to have epilepsy and what it is like.

I think the biggest battle has been getting people to listen to me, and trust that I know how I feel and what is best for me. I have also been amazed by how frightened people can be by the word ‘epilepsy’. There is also the idea that because I don’t have tonic-clonic seizures, it isn’t ‘real’ epilepsy or that the problem is psychological.

Since being diagnosed and being given appropriate treatment, I am feeling better than I have for many years. I still have strange episodes and problems with my memory, but they are much less severe now. I am back to working and doing all of the things I enjoy. On the positive side, I sometimes experience a wonderfully heightened sense of perception and a deep sense of wonder in the world. It’s almost like a secret that I can see, but others can’t.

Consultant neurologist Mark Manford explains the principles behind analysing experiences like Rebecca’s – and examines how those experiences are caused by activity in the brain

Our understanding of how the brain works is linked with our knowledge of epilepsy, so a little history is appropriate here!

In the UK in the late 19th Century, Hughlings Jackson described different kinds of focal epilepsy, arising in different parts of the brain. (These included the ‘dreamy state’ of Dr Z – see over.) Jackson compared these epilepsies against the findings of the autopsies done on people with epilepsy who had died. In this way, he was able to define where in the brain different seizures came from. This was a turning point in epilepsy analysis. The next key advance was the development of the human EEG by Hans Berger in 1920. For the first time, clinicians could look at the electrical activity causing the seizures that underlie symptoms like Rebecca’s.

Meanwhile, Dr Wilder Penfield founded the Montreal Neurological Institute in Canada in 1934. Soon after the invention of the EEG, Dr Penfield started performing operations for temporal lobe epilepsy (TLE) like Rebecca’s. During these operations, Dr Penfield recorded spontaneous seizures. He also deliberately stimulated different areas of the brain with electricity in awake patients during surgery. (Operating on patients when they are awake sounds scary. It is quite safe, however, if you numb the layers covering the brain. The brain itself doesn’t feel anything.)

By noting down the results of this stimulation, Dr Penfield could figure out what each section of the brain did. He made brain maps of higher mental functions. These have since been developed with modern techniques, such as radioactive isotope scanning (PET and SPECT) or functional MRI scans. These follow increases in blood flow and metabolic activity (chemical reactions) in the brain, which highlight seizure activity. These techniques are also used in the research lab – where people perform different tasks, while researchers watch to see which parts of the brain are being used.

The temporal lobe – the section of the brain that is the focus of Rebecca’s seizures – is involved in memory. Although not always the case, the temporal lobe on the left usually specialises in language-based tasks (like doing a crossword). The temporal lobe on the right usually specialises in visuospatial tasks (seeing the relationships between shapes – like doing a jigsaw). The temporal lobes are closely connected by pathways in the brain.

Meanwhile, a structure deep in the temporal lobe – called the hippocampus – is like the librarian for memory. In evolutionary terms, this is an ancient part of the brain. It is crucial in storing and retrieving memories. Another small area situated at the tip of the temporal lobe is called the amygdala. It is particularly involved in emotional reactions, while very close to it are regions important in smell and taste.

This ancient combination is called the mesial temporal lobe. You can imagine why it is so important. If you eat something poisonous, for example, this could kill you. A system like the mesial temporal lobe – which generates a strong emotional response and vivid memory – will keep you alive. Have you ever eaten anything that gave you food poisoning? How did you feel about that food afterwards? When did you eat it next?

The brain works using electrical impulses carried by many brain cells, or neurons. Normally, these are in finely tuned patterns to allow the countless feelings and perceptions of human experience. Focal seizures are like little       thunderstorms that start in one part of the brain. The storm may remain there or spread to another part – and may cause unusual sensations in the mind or body as it goes.

Rebecca’s brain

The early symptoms of a seizure can be very useful. We can use our knowledge of brain function – partly acquired by historical study – to work out where seizures start. The early symptoms are often a corruption of the normal function of the part of the brain where the seizure starts.

Specifically, Rebecca’s seizure is mimicking the action of a memory being retrieved from storage in the brain. This immediately points to the hippocampus as a likely source. The hippocampus is especially likely to cause seizures. Scarring of the hippocampus is the most common cause of focal epilepsy.

The memories Rebecca experiences are emotionally important – for example, her pet dog and the day she wore special new clothes. Although, interestingly, she does not relive the emotion that went with it as some patients do. She also has a feeling of fear. Electrical stimulation of the amygdala may commonly cause fear and anger, so involvement of the amygdala is likely.

The memories are mostly visual ones. Some researchers argue that this means it is more likely to come from the right temporal lobe (although that is disputed by other researchers). Some people call it deja vu when someone relives an experience like Rebecca has. Technically, this term should be reserved for a sensation that most of us have had, especially when tired. That is the sensation that the environment in which you find yourself is very familiar, as if you’ve been there before.

In someone with epilepsy, this sensation is much more intense and the feeling of disorientation that deja vu gives is very similar to what Rebecca describes. It is her own experience that comes back to her, so it feels completely real – and there is a moment in which she is uncertain of reality. There is an associated taste with some of her attacks. This hints that the parts of the temporal lobe involved in taste are involved in the seizure activity. Rebecca also experiences a rising feeling in her stomach. This suggests that the seizure has spread to parts of the brain close to the temporal lobe that are involved in controlling the gut and its sensations.

An MRI scan is likely to show hippocampal scarring (also termed ‘mesial temporal sclerosis’). Quite a lot of patients with this sort of epilepsy have a history of a prolonged convulsion with fever as a very young child. If Rebecca’s epilepsy was difficult to treat, she might benefit from investigation into possible epilepsy surgery. Her story implies that she might be a very suitable candidate.

Many patients with TLE have no convulsive seizures and this often leads to a major delay in diagnosis. Alternative diagnoses, usually psychiatric, are made instead. This is distressing for patients who cannot understand their symptoms in those terms and, of course, leads to failed treatment.

Has your epilepsy has led to strange feelings, sensations or experiences? Would you like to submit your story for a future Doctor, doctor feature? If so, email the editor at pfox@epilepsy.org.uk or write to him at Epilepsy Action headquarters.