Science

Scientists discover On/Off switch in human brain

Scientists claim to have found an ‘on-off’ switch in our brain that can bring people in and out of consciousness.

Dr Mohamad Koubeissi and his team from George Washington University studied an epileptic patient and found that electrical impulses of a specific region sent her to ‘sleep’ on repeated occasions.

Stopping the stimulation of the brain brought her out of the vegetative state – and she had no recollection of what had just happened.

Consciousness is the state of being aware of one’s surroundings; a lack of it can commonly be associated with sleeping.

How consciousness works, though, is a bit of a mystery – indeed, the exact reasoning behind why and how we sleep is still up for debate.

The discovery of this on-off switch, as reported by New Scientist, could therefore be very useful in certain areas of medicine.

In the clinical trial, the researchers employed low-frequency deep brain stimulation to try to help reduce epileptic seizures in patients.

Dr Koubeissi, who led the trial, found that low-frequency stimulation reduced epileptic seizures in patients by 92 per cent without impairing memory.

‘This is an innovative clinical trial that aims to identify novel modalities to reduce seizures in individuals with medically-intractable temporal lobe epilepsy, who are at risk of sustaining memory decline with the surgical removal of the temporal lobe,’ he said.

‘Over the next few years, we hope that the results will be similar to previous research, leading to better treatment options for these patients.’

When they switched to high-frequency electrical impulses, however, they discovered the fascinating on/off effect.

Claustrum
The effect was produced by stimulating the patient’s claustrum (a thin sheet of neutrons at the lower part of the central brain, shown by the red arrow). Once stimulation of the claustrum stopped the patient regained consciousness, and was unaware of what had happened.
One exciting possibility for the discovery could be that, for people who are trapped in low states of consciousness, such as people in a coma, the region could be stimulated to help regain a conscious state. The next step will be to emulate the effects in other patients.

 

Stimulating the 54-year-old patient’s claustrum – a thin sheet of neutrons at the lower part of the central brain – the researchers found that she lost consciousness.

This meant she didn’t respond to commands and also just stared blankly into space, while her breathing also slowed.

Once stimulation of the claustrum stopped she regained consciousness, and she was completely unaware of what had just happened.

Over two days, every time the claustrum was simulated the same thing happened – with additional study confirming this wasn’t just a side effect of a seizure.

To New Scientist, Dr Koubeissi likened the effect to the ignition on a car, explaining that turning a key brought all the other components of the car to life.

One exciting possibility for the discovery could be that, for people who are trapped in low states of consciousness, such as people in a coma, the region could be stimulated to help regain a conscious state.

The next step will be to emulate the effects in other patients to further see just what role the claustrum plays in consciousness.

DailyMail

Share this story