Sharing the vision epilepsy: life’s turning point Gavin Dimitri

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THE EPILEPSY REPORT OCTOBER 2008

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                          THE EPILEPSY REPORT OCTOBER 2008

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any children with epilepsy appear 

to have memory and learning 

problems. Over time both the medication 

and the epilepsy can delay learning 

ability thus impacting on self-esteem. 

Often feeling threatened at school, the 

child’s ability to achieve schooling 

outcomes decreases.  

Children’s memory and learning needs 

are very important to The Epilepsy 

Centre SA. Assisted by students from 

Flinders University Department of 

Psychology, The Epilepsy Centre 

recently ran a four day Learning and 

Memory Workshop for children.  

While there are a variety of ways 

in which children learn, it seems that 

many of these children learn visually 

or kinetically. So, with this in mind, 

workshop activities were designed for 

improving both short term and long 

term memory. Based on the structure 

of ‘how to remember’ the workshop 

incorporated the techniques of memory 

by association; visual awareness; the 

art of location; the art of imagination; 

method of loci; painting a memory in the 

mind’s eye; the art of observation; the 

art of concentration and focusing. This 

incorporated the five senses – tactile, 

sight, hearing, smell and taste.  Mind 

mapping was used along with colour (to 

excite the brain for visual appearance).  

A memory game along the lines of a 

Treasure Box was re-constructed. The 

children chose an object which they had 

to observe, placed it in the Treasure Box, 

recalled the fine details of that object, 

and then recreated it by using modelling 

clay.  

Both the Treasure Box and the 

sculpturing of the object supported long 

term and short term memory. 

Knowing that life today can be 

stressful for both children and parents, 

it was important to develop strategies 

to assist with the children’s wellbeing.  

Specific lifestyle information was 

included in the workshop and the 

children were supported by three 

speakers who gave them a balanced view 

on eating, exercise and education. 

Daniel, from the Arthur Murray 

Dance Studio, assisted the children 

Children’s memory 

and learning workshop

in learning various dance steps. This 

helped with coordination, team work and 

cooperation that is all essential for good 

education health.

The enthusiasm and dedication of the 

Flinders’ students was exceptional. The 

children delighted in the attention they 

received and benefited from the one 

to one working relationship with the 

student placements.

 During the four days the children 

had lots of fun painting, building a 

paper mache volcano that actually 

erupted, eating their lunch outside 

in the sun. Group time together was 

spent playing games. The active 

participation increased their confidence 

in communicating and working together 

as a team.

Due to the success of this workshop 

The Epilepsy Centre, SA plans to run 

future programs during the school 

holidays.  If you are interested in 

sponsoring this program or can assist 

in anyway please contact the Client 

Services Team on 08 8448 5600. 

 

Epilepsy Research at Flinders

 

Epilepsy Research Group 

Flinders University and Medical 

Centre

Part 3: Gamma rhythms & seizures?

   

In part 2 (The Epilepsy Report, May 

2008), we concluded that fast EEG 

rhythms, around 30-100 oscillations per 

second called “gamma” rhythms, were 

present at very high intensity in rats 

or humans prone to certain seizures. 

We detected gamma rhythms in our 

experiments in both rats, in which we 

cause seizures, and in humans, who 

have ongoing epilepsy. We proposed that 

gamma rhythms might be important in 

increasing the likelihood of seizures.

This article explains what we have 

done to identify how high intensity 

gamma rhythms might lead to seizures. 

Our first idea proved a dead end, the 

second idea proved fruitful.

What happens to brain chemistry 

during fast brain rhythms?

In our rats, we are able to investigate 

what happens in and around brain 

cells while there are high intensity 

gamma rhythms. During a number of 

different and technically sophisticated 

experiments, all approved by Flinders 

Animal Welfare Committee, we 

tested whether there were any changes 

in potassium or calcium (ion-) 

concentrations in the fluid surrounding 

the brain cells during the increased 

gamma rhythms. You may ask why 

this would be expected and why even 

bother to look? The answer is that 

nerve cell excitability is affected by the 

concentration of ions and other chemicals 

in the fluid in which brain cells are 

situated. This is partly how things like 

drugs, alcohol, and hyperventilation, all 

of which affect the environment within 

the brain, can induce seizures. 

Two ions known to have a substantial 

affect on the excitability of brain cells are 

potassium and calcium. By measuring 

them and at the same time measuring 

EEG in our rat experiments, we could 

test whether they changed during the 

increased gamma rhythms we saw before 

seizures. Calcium and potassium did 

not change at all during the intensified 

gamma rhythms.

Figure 1. From the work of Dr Marita 

Broberg, showing 20 minutes of an 

experiment in a rat in which gamma 

EEG activity has developed. Gamma 

EEG is present both between and during 

seizures. The top part of the figure 

shows the 

concentration 

of potassium 

in the brain 

during the 

experiment – 

the potassium 

is the same 

as it was at 

the beginning 

of the 

experiment 

(not shown 

here). 

Potassium only changes with some  of the 

seizures.

These negative findings were 

disappointing to us, but they were clear 

and we examined other connections 

between intensified gamma rhythms 

and seizures. We should say that when 

the actual seizures occurred in our 

experiments, there were potassium and 

calcium changes, due to the massively 

synchronised brain cell activity. These 

were expected because they have been 

reported previously on many occasions. 

Now to the next idea …

Is there swelling of individual brain 

cells during fast brain rhythms?

As we mentioned above, a stable 

chemical environment is needed for 

the proper function of the brain’s nerve 

cells. This environment is regulated very 

carefully in the brain by special cells 

called astroglial cells. It is now known 

that these cells also communicate with 

the nerve cells providing them with 

energy and removing neuronal chemicals 

released during brain activity. In order to 

regulate the environment, astroglial cells 

have to take up nerve chemicals and ions 

and doing this causes them to swell.

  Using a sophisticated, painless 

electronic technique called ‘impedance’, 

we were able to measure cell-swelling 

during our seizure experiments. To 

our delight, we could see a close match 

between the amount of gamma rhythm 

activity and the amount of cell-swelling 

before different types of seizures.  The 

next figure shows the result. This kind of 

graph shows that there is a relationship 

between more gamma EEG and more cell 

swelling.

Figure 2. This graph shows an 

important experimental result: as the 

amount of gamma EEG increases, so 

does the amount of cell swelling.

These findings confirmed the 

importance of intense gamma rhythms 

in the promotion of seizures, because it 

is known that cell swelling is one factor 

increasing the electrical excitability 

between nerve cells.

For people with epilepsy: 

what have we learnt from our 

experiments?

As described in our previous article, 

there is intense gamma EEG in some 

people known to have epilepsy. From our 

rat studies, we therefore suggest that part 

of what makes some of our brains prone 

to epileptic attacks is slight swelling 

of brain cells caused by the intensified 

gamma EEG. The swelling then makes 

nerve cells even more easily activated by 

other nearby cells and more easily prone 

to abnormal spreading of the brain’s 

electrical activity – causing seizures.

In the next article we will describe yet 

another situation in which cell-swelling 

occurs, a form of swelling which, we 

think, may be an immediate trigger of 

seizures. For this we will focus especially 

on the few seconds preceding the actual 

start of a seizure. 

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