London: Scientists have unveiled a new feel good "patch" which they say could help fight depression while you sleep.
Developed by researchers at the University of California in Los Angeles, the device when stuck on to the forehead uses tiny electrical impulses to stimulate the trigeminal nerve in the head.
This nerve, which sits just beneath the forehead and often described as the "USB port into the brain", leads to areas in the brain which are thought to control mood, the Daily Mail reported.
The device, which contains electrodes, is linked by two wires to a generator the size of a mobile phone, which can be worn around the waist.
In a trial on a small group of patients suffering from major depressive disorder, the researchers found the patients reported a 50 per cent reduction in symptoms after using the patch for eight hours a night for eight weeks.
The patients, who had all suffered from major depressive symptoms for more than four months and not responded to at least one antidepressant, reported feeling better after just two weeks, the researchers said.
The device didn`t disrupt the patients` sleep, but they did report a tingling sensation when it was first turned on.
Dr Christopher DeGiorgio, a neurologist at UCLA who had originally devised the device called the Neurosigma to treat epileptic seizures, said: "One of the patients on the original epilepsy trial said his epilepsy symptoms hadn`t improved but his wife told us he was more alert and more communicative."
"Although he hadn`t been diagnosed with depression, he had previously been melancholy, and mood disorders are very common in people with epilepsy."
After this observation the team used Positron Emission Tomography (PET) scans to measure blood flow in the brain, and found that stimulating the trigeminal nerve can affect mood.
"We found within seconds of stimulating the trigeminal nerve, there were changes in blood flow to areas of the brain which affect seizures, mood and concentration," Dr DeGiorgio said.
The team is unclear how the electrical stimulation boosts
blood flow, but said the nerve impulses could tell the brain these areas are in use, and so need a greater blood supply.
One particular area of the brain that showed an increase in activity is called the anterior cingulate cortex, which is involved in mood, the researchers said.
The new device, they said, could be a useful treatment for patients for whom antidepressant medication has failed.
It may also be an option for those who can`t tolerate the side-effects of antidepressants, which include nausea, weight gain and sexual dysfunction, they added.