By Rodrigo Pérez Ortega*
The brain is one of the body’s most important organs and the hardest for science to decipher. Anthropological research calculates that it took three million years to evolve (from Australopithecus to modern humans).
One of the most complex fields of medical research is that of drugs for treating brain diseases. Both motor and psychiatric diseases are the hardest to treat, as medication often fails or doesn’t work.
In Parkinson’s disease, the neurons that produce dopamine in the basal ganglia of the brain (which are essential for muscle movement) gradually stop working properly. Patients’ hands tremble uncontrollably, and basic movements become complicated. The drug levodopa or L-DOPA can increase dopamine levels. However, it isn’t very effective for many patients.
Neurons speak the language of electricity. In order for them to communicate with each other, these cells send tiny discharges through their axons, thus causing the release of neurotransmitters (the brain’s chemical messengers), which pass the message to the other neurons.
You could read: 10 visible and invisible symptoms of Parkinson’s
Deep brain stimulation is the last resort for many patients with Parkinson’s. In this treatment, two slender electrodes are placed in the brain (in the region of the basal ganglia) and produce electrical impulses. Just like a pacemaker, some thin wires passing under the skin connect a device installed in the chest to the electrodes. This allows the frequency and intensity of these discharges to be controlled.
Going about your daily life with two electrodes in your brain could seem like something out of a science fiction novel or a cyborg movie, but patients’ improvement with these devices is impressive. It’s painless, as the brain is unable to feel pain. In a matter of seconds, patients who had hand tremors and problems with walking suddenly don’t anymore when the device is activated.
Deep brain stimulation was developed accidentally in 1987 by Doctor Alim-Louis Benabid, a French neurosurgeon and physicist, when he noticed that the tremors of a patient with Parkinson’s disease stopped during surgery after applying an electrical discharge at a frequency of 100 Hz.
It’s a curious fact that 30 years after its invention, nobody knows exactly how this minimally invasive procedure works, but some researchers have suggested that it recalibrates the electrical activity of circuits that are functioning abnormally.
This technique, which is a blessing for some, has also been approved by health authorities for treating certain types of epilepsy and obsessive-compulsive disorder. Recently, it has proved very effective in experimental trials at treating other ailments such as depression, addictions, chronic pain, multiple sclerosis, and strokes. However, as with any surgery, the procedure involves risk. There’s always the possibility that it won’t be so effective, and patients will have to continue taking drugs.
*Rodrigo Pérez Ortega is a science communicator and neuroscientist.