A case study published by a team of Taiwanese neurologists reported a most unusual set of circumstances.

One of their 41 year-old female patients, diagnosed with epilepsy, had a seizure every time she brushed her teeth. Seizures in response to external stimulation are not unusual - flashing lights are a well known source - and other sorts of stimulation are not uncommon triggers. A recent case-report even involved seizures induced by vacuum cleaner use.

So the unusual aspect for the Tiawanese case was not the trigger, but the effect of the seizure. The woman had seizures when she brushed her teeth, and had an orgasm every time she had a seizure, shortly before losing consciousness.

Although probably doing wonders for her dental health, the condition has left neurologists rather puzzled. Because so little is known about sex and the brain, her doctors had very little to go on when they tried to explain what was happening.

Sexual neuroscience is one of the most under-researched areas in the human sciences. A quick search of PubMed (the international database of medical research) shows that we know more about the neuroscience of hiccups than we do about orgasm.

Part of the problem is practical. fMRI scanners, some of the most useful and popular tools in cognitive neuroscience, involve lying in a tube while scanning takes place and need the head to be completely still. Add the fact that you're being watched by neuroscientists and none of this makes for relaxed coupling, or even self-stimulation.

Nevertheless, pioneering researchers have tried to tackle the problem with other methods. A Dutch team led by Gert Holstege used an alternative form of brain scanning, known as Positron emission tomography or PET, to study orgasm in men. PET doesn't have the same cramped conditions as fMRI allowing for a bit more sexual freedom in the lab.

They still had some considerable problems to overcome though, not least of which was timing an orgasm to occur during a predefined time-slot, during which brain activity could be monitored. PET requires a radioactive tracer to be injected into the bloodstream, and although the radiation is very weak, it's best to use only as much as necessary. This means the intuitive approach of continuous scanning and waiting for the pop of the cork is just not feasible.

Instead they asked couples to practice at home. The participant's partner (who had the more difficult task by far) needed to be be able to make her partner ejaculate - while he was standing, being injected by radiation, watched by neuroscientists and, most importantly, during a precise 50 second time-slot.

With all credit to the women involved, 8 ejaculations were recorded from the eleven men who volunteered.

The research team found that brain activation is not dissimilar to the effects of certain drugs (the authors mention heroin), showing greatly increased activation in a deep midbrain area called the ventral tegmentum, an area linked to reward, desire and pleasurable experiences.

In contrast, comparitively little cortex activity is involved in the male orgasm. The cortex is typically considered the source of complex thought and mental co-ordination, and Holstege's team put most of the activity here down to erection and sensations in the penis. Men it seems, are more than capable of thinking with their dicks, even when being injected with radioactive tracer.

Sadly, even less is known about the neuroscience of female sexuality and orgasm. Not least because, as many men (and I'm sure women) will testify, the female orgasm is sometimes difficult to predict.

But a far greater problem is the perception of this sort of research. It's exactly the sort of science that the press loves to go giggly about. News stories tend to be gleefully reported, virtually free of any actual news. "Sex researchers study sex" seems to make headlines where "hiccup researchers study hiccups" seems to barely raise a byline.

This type of reporting tends to put off scientists, who want to be seen as serious researchers, and funders, who want to be seen as supporting important research. Science marches on however, and luckily for us all, some scientists are not disuaded by the accompanying media circus.

But if it takes your fancy, you could always volunteer as a participant yourself. Neuroscience studies take various forms, and many involve nothing more than having a few electrodes stuck to your head.

Importantly, participation is confidential and you would be contributing towards progress in neurology and neuroscience, but most deliciously, it's a fantastically unusual way to spice up your sex life.