Mind controls: Eight new tools to boost your brain
* 11 April 2011 by Clare Wilson
No need to drill a hole in your head: ultrasound, light and magnetic fields can be used to mess with your mind
I’M WATCHING this revolution exploding around me,” says Mark George, a neuropsychiatrist at the Medical University of South Carolina in Charleston. “I’m like a kid in a candy store.”
George is referring to his role as editor-in-chief of Brain Stimulation, a journal launched three years ago to cover the growing list of technologies that can alter the brain’s electrical activity. The tools involved range from electrodes and optical fibres to magnetic fields and sound waves, but they all give neuroscientists the power to fine-tune the brain’s activity, making them computer hackers of the mind.
Fifteen years ago, only a couple of such technologies existed and they were seen as experimental techniques on the fringes of neuroscience. Today there are at least eight methods, all with their own pros and cons, and some are on the verge of becoming mainstream treatments for Parkinson’s disease, epilepsy and depression. Innumerable more uses are being explored.
Until recently the only treatments available for conditions affecting the brain were drugs or surgery – a “hammer over the head approach”, according to William Tyler, a biomedical engineer at Virginia Tech Carilion Research Institute in Roanoke and a pioneer of the new brain stimulation techniques.
Drugs work by interfering with the chemical signals that pass between neurons. Unfortunately, such chemicals are used widely throughout the brain and body for different functions, leading to unwanted side effects. Drugs for Parkinson’s disease, for example, can turn people into compulsive gamblers, while many antidepressants increase people’s appetite or reduce their sex drive. “People talk about ‘brain serotonin’,” says George. “But it can do divergent things in different parts of the brain.”
Brain surgery, in contrast, can target a tiny area, but it carries risks and is permanent. One treatment for Parkinson’s, for example, is to burn the pea-sized sites deep within the brain whose overactivity causes the symptomatic tremors. If the wrong tissue is destroyed, however, there is no undoing it.
It was this pitfall that led to the development of electrical brain stimulation. In surgery to treat Parkinson’s, the spot causing the tremors is homed in on by pushing an electrode into the brain and delivering a current that has characteristic effects on the patient, who is awake during the procedure. In 1987, French surgeon Alim-Louis Benabid found that passing a higher frequency current through the electrode stopped the neurons firing, eradicating the tremor without destroying tissue.
Since then, other techniques have been developed that site electrodes outside the brain or harness different forms of energy. As well as treating various illnesses, though, could such techniques boost our existing mental abilities? If something can treat depression, why can’t it be used to eradicate everyday sadness? If the memory decline associated with Alzheimer’s disease can be reversed, could the same technique make us all a bit smarter?
It may sound far-fetched, but consider how quickly prescription drugs to treat hyperactivity or fatigue have grown from medicines to enhancers. Surveys suggest up to a quarter of students at some US universities take these drugs to improve their performance, as do around 1 in 5 scientists (Nature, vol 452, p 674).
In the articles below New Scientist explores a number of brain stimulation technologies. It’s not an exhaustive list, but it does highlight some of the most promising emerging technologies to manipulate our minds.
Mind controls: Wires in the brain
Deep brain stimulation gives a direct line to areas where electric current can ease conditions from Parkinson’s to obsessive compulsive disorder
Mind controls: Running electricity through the skull
Transcranial direct current stimulation helps people recover from stroke – and boosts learning of both manual and mathematical skills
Mind controls: Electrodes sitting on the brain’s surface
Epidural cortical stimulation is a halfway house: you do get a hole in your head, but no wires in the brain, and it has helped severely depressed people
Mind controls: A traffic cop on the nerve superhighway
The vagus nerve connects your brain to many major organs. Stimulating it can treat epilepsy and depression – and might even curb overeating
Mind controls: Good vibrations reach deep in the brain
Ultrasound focused within the skull can trigger movement in animals – could it give us a safe way to plug technology into the brain?
Mind controls: Magnetic relief for depression Movie Camera
Transcranial magnetic stimulation lets us turn parts of the brain on or off at will. It can ease depression too, and a handheld device may be on the way
Mind controls: Putting a light switch in the brain
With optogenetics, researchers can implant optical fibres to control genetically modified animals – could gene therapy bring it to humans?
Mind controls: How magnets make the worm turn
Magnetogenetics is a new spin on optogenetics, using magnets instead of fibre optics to turn nerve cells on and off