But a study in the New England Journal of Medicine shows delivering electrical impulses to that same area of the brain may be just as effective, with fewer serious side effects.

Researchers in Amsterdam tested 67 volunteers and found electric stimulation dampens the tremors the same way as destroying a small area of the brain does. But the newer technique, thalamic stimulation, is less destructive than the traditional surgery, known as a thalamotomy.

"For the time being, thalamic stimulation is preferable to thalamotomy as a means of improving function with few adverse effects," researchers said.

However, neither treatment is effective in all patients.

The focus of the research is the thalamus - two joined walnut-sized bundles of nerves located near the core of the brain. They serve as a relay station for electrical impulses.

In a thalamotomy, doctors severely damage one bundle of nerves by inserting a probe and heating the tip to 80 degrees Celsius for one minute. The procedure helps relieve incapacitating tremors in 73 to 93 per cent of patients, but causes permanent complications in up to 41 per cent of cases.

With the electrode procedure, surgeons insert a wire with four electrodes into the thalamus. The electrodes are connected to an implanted device that generates electrical pulses.

In the Amsterdam study, Dr Richard Schuurman and his colleagues at the Academic Medical Centre compared the results of 34 volunteers who underwent the traditional surgery with 34 treated with four implanted electrodes.

With both treatments, the results were dramatic. In the people with the thalamotomy, 26 said they had a complete suppression of their tremors after six months. The same was true for 28 volunteers treated with the electrodes.