Parkinson's disease

Parkinson’s disease: The latest research

There have been a number of groundbreaking discoveries in recent years. Here we outline research that may provide Parkinson’s disease treatments for the future.

Treatment of Parkinson’s Disease

1. Deep Brain Stimulation


Deep brain stimulation involves implanting an electrode into a part of the brain called the subthalamic nucleus. The electrode delivers electrical signals that can almost miraculously alleviate the symptoms of Parkinson’s in some people. It is thought that one in five people with Parkinson’s would benefit from deep brain stimulation.

2. Implanting human embryonic cells

This technique takes dopamine-producing tissue from aborted human embryos and implants them into the damaged areas of the brain.

Professor Steven Dunnett, a leading scientist in this field says of the trials, “There have been clear benefits in a small number of carefully studied patients”.

However he adds, “due to the complex ethical issues and practical difficulties of using human embryonic tissue, it is unlikely to become a widespread therapy. It does however prove that transplantation of the right cells can work”.

3. Implanting stem cells

Professor Dunnett’s lab are also leaders in stem cell research. They see these as a safer and more likely alternative to tissue from human embryos (what are stem cells?). Using expertise gained through embryonic cell transplants, Steve Dunnett’s team are working to increase survival of the transplanted stem cells.

4. Keeping cells alive

Another promising option is to use compounds known to protect neurons from further damage. However, getting these compounds to the correct part of the brain is proving a huge challenge.

5. Infusing ‘Growth Factor’ into the brain

Another pioneering surgical treatment involves implanting a pump filled with GDNF in a patient’s abdomen. This sends a daily dose of growth factor into the dopamine deficient area of their brain.

The growth factor, called GDNF (glial-derived neurotrophic factor) encourages the recovery of damaged neurons.

Legal and ethical issues

The USA and Europe have very different laws regarding what is, and what is not, ethical. Using brain tissue from animals and transplanting them into humans (xenografts) is hugely contentious in Europe because the effects are unknown. However, in the USA it is considered ethically acceptable.

In the USA the federal government will not fund stem cell research as it considers it ethically unacceptable. In contrast, stem cell research is legal in most of Europe.

Steven Dunnett concludes:

“Stem cell researchers are moving from the States to Europe, and xenograft researchers are moving from Europe to the States. The most promising treatments will be dictated by social and ethical regulations”.

For more information, visit the Parkinson’s disease society website

how sensitive are you

How Sensitive are you?

Are your lips more sensitive than your fingertips? Is the skin on your legs as sensitive as the skin on your arms and have our chimp-ancestors left us with feet as sensitive as our hands? To find out, try our two-point discrimination experiment. All over your body you have tiny pressure sensors in your skin. Some areas have many pressure sensors and other areas have relatively few. Areas where the pressure sensors are packed in are very sensitive to touch.  

This two-point discrimination experiment lets you discover which parts of your skin have many pressure sensors, and where they are relatively sparse. The experiment involves gently pressing two sharp points onto a friend’s skin and asking them whether they can feel one or two pressure points. 
 In sensitive areas, the pressure sensors are closer together, so the two tips of the paper clip will activate two separate pressure points. Messages from both sensors are sent to your brain and you feel both tips. In less sensitive areas, the pressure sensors are further apart, so both tips activate only a single pressure sensor. A message from this sensor is sent to your brain, and you only feel one tip on your skin. 

For this experiment you will need: 

A paperclip
A pen and paper
A ruler
A friend 

You can also try this on your own, with your eyes shut, concentrating on what you feel. 


1. Straighten out a paper clip and bend it into the shape of a U. Make sure the tips are level with each other. 
2. Now, ask a friend to close their eyes. Arrange the ends of the paper clip so they are about 1 cm apart. 
3. Touch both ends of the paper clip gently (and at the same time) onto the back of your friend’s hand and ask if he or she felt one pressure point or two? 
4. If your friend felt only one pressure point, spread the tips of the paper clip and try again. Write down the distance where your friend goes from feeling one pressure point, to feeling two pressure points. 
5. To make it difficult for your friend to guess the answer, vary both the distance between the tips, and whether you actually place one or both tips on their skin.    

Try this test on the palm and back of the hand, fingertips, forearm, upper arm, shoulder, back, neck, cheek, forehead, lips, nose, legs, tips of the toes, soles and upper parts of your feet. 

Which part of your body can two points be detected with the smallest tip separation? This is the most sensitive part of your body. Below are some approximate values for this two-point-discrimination test (from The Skin Senses, edited by D. R. Kenshalo)
Fingers 2-3 mm
Upper lip4-5 mm
Cheek 6 mm
Nose7 mm
Palm10 mm
Forehead35 mm
Belly30 mm
Forearm35 mm
Upper arm39 mm
Shoulder41 mm
Thigh42 mm
Calf45 mm
Foot20 mm

Dancer brain

The Dancers Brain

Do professional dancers have different brains from the rest of us? What part do mirror neurons play in dance, and can movements you learn really change what you see? 

These were all questions asked by neuroscientist Dr Daniel Glaser and colleagues from University College, London. “The inspiration for the study came from watching Olympic divers. The commentator was saying ‘and that was a double somersault with one and a half twists’ and I could barely see these movements. It got me questioning what was different about the brains of people trained in physical activities”

Ballet or capoeira

For their study, Daniel and colleagues looked at professional male dancers trained in either ballet or capoeira ( a Brazilian martial art). They scanned the brains of these dancers as they watched videos of both dance styles. What they found was rather intriguing…
The visual areas of the brain showed activity. But the real differences were found in two areas related to movement – the pre-motor cortex and the visual-motor integration cortex. Both these ‘movement’ areas of the brain showed more activity when a skilled dancer saw movements he had been trained to perform, compared with watching movements he hadn’t been trained to perform. It was as if the movement part of his brain was resonating with the moves he knew. 


Click here
 to hear Daniel Glaser talk about these results Other people (ie those who weren’t dancers) were also scanned. There was no difference in their brain activity whether they watched ballet or capoeira – their brains did not discriminate. This shows that the dancers combine what they saw with their own personal ‘motor repertoire’ – and this shows up differently in their brain scans. It also shows that by lying still and simply watching other people move, you can activate movement areas of the brain as if you were moving yourself! 

Your astounding ‘mirror neurons’

Scientists have known for many years that when a monkey reaches out and grabs a peanut, motor command neurons fire in his brain. A different, nearby neuron will fire when that monkey for example pulls something towards him. Giacomo Rizzolatti working in Italy has discovered these same neurons fire when a monkey simply WATCHES another monkey grabbing a peanut, or WATCHES another monkey pulling something towards him. This is a truly fantastic discovery because the visual image of someone else grabbing a peanut is entirely different from the image of yourself doing it. It implies a different type of representation. Early results suggest that humans have more extensive mirror systems than monkeys. 

Why do we have mirror neurons?

Mirror neurons are likely to be vitally important to human behaviour – to interpret other people’s actions and intentions. They have probably been fundamental to our evolution, allowing us to imitate our parents and quickly transfer skills and culture to the next generation.

Why is this experiment important?

These findings might one day help people who have lost movement due to a stroke. Once the brain has learned a skill, it’s possible to stimulate this brain area by watching someone else do the activity. Perhaps greater knowledge of the mirror system could help injured athletes and dancers. They could continue to train without moving a muscle – by simply watching someone else do the movements until their bodily injury had recovered. There is also an appealing though completely untested idea that maybe disorders such as autism are in some way related to disruption of these mirror neuron systems.