Some patients can stay in a coma for weeks, months, or even years, but what leads to a few of them actually recovering from a coma?

Prolonged Loss of Consciousness

A coma is defined as an extended period of unconscious awakening caused by some injury, inflammation, or infection in the brain. The brain networks do not communicate the way they do in usual times.

A person who is in a coma is alive, but cannot move at will. In most cases, the patient is not able to think, talk, or respond to the environment. Essential biological functions, such as blood circulation and breathing, are also likely to be hindered in most cases.

The longest documented case of a coma was Munira Abdulla, who fell into a coma in 1991 from a car accident and woke up 27 years later.

READ ALSO: Ultrasound Jump Starts Two Coma Patients' Brains

How Does a Person Recover From a Coma?

According to psychology professor Martin Monti from the University of California, Los Angeles, experts do not really know how a person recovers from a coma. That is why they still do not have many interventions to help people recover.

Before one wakes up, the brain should heal from injury through the regrowth of the damaged neurons. It may also expand on other brain networks to take over the job of the injured brain region.

However, this physical recovery of the brain network is not enough since the coma also slows brain activity. In other words, everything comes a little bit more silent, according to Monti.

The brain may need some kind of jumpstart in order for it to get back up to speed and lead someone to wake up. There are ways in which doctors can potentially trigger such a jumpstart in the brain.

One way to do this is through the use of amantadine, a drug that basically boosts the quantity of dopamine in the brain. It is used sometimes to effect Parkinson's disease since this drug is also believed to augment the quantity of released dopamine by the neurons while at the same time preventing recycling too rapidly.

Another approach is deep brain stimulation, where electrodes are surgically placed deep in the brain, delivering a mild amount of electricity to excite the neighboring neurons. The stimulation targeted the thalamus, generally a region of the brain that helps control attention and arousal, according to the 2018 review.

There is another technique called focused ultrasound, where the doctor attempts something similar to ultrasonic vibration and without surgery. Deep brain stimulation through magnetic stimulation is conceivable.

For any of these therapies meant to speed someone's return to consciousness, the structure of the brain itself must be intact.

Still, many coma patients never wake up. The proportion reported as never gaining consciousness varies between 20% and 40% of those who suffer from this disorder. One study of persons in comas in the US and the UK found that 54% of coma patients died, while 15% survived but with poor outcomes, and only 31% survived with good outcomes.

The process of how and why people come out of comas, either by themselves or jumpstarted by medication or therapies, remains in large part a mystery. As scientists work closer to solving this, they can become better at waking people up from comas faster.

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Check out more news and information on Coma in Science Times.