What is consciousness and how does it arise in the brain?

Consciousness is a strange thing. Researchers have been trying for too long to find out how consciousness works.

The mind-brain thing has been a topic of mystery for a very long time.

We have travelled to the space and have explored galaxies and searched for extraterrestrial life. We  have identified many organisms in the deep seas. 

We have discovered cures for many diseases that were once fatal. And, we have also come up with so many highly useful technological advancements.

Yet, we still don’t know where consciousness resides in the brain.

Consciousness is so interesting – we lose it while we sleep. It can be changed in strange ways by drugs, and it can be affected due to a serious injury.

 We don’t know which part of the brain is responsible for consciousness and how mindful thoughts and activities emerge from that little organ.

Cognitive functions in the brain are so internal and private. It is not just about being conscious about things or being aware.

There is a whole lot of other dimensions involved – for instance perception.

When you and me see the same thing, I can only experience my own perception of that thing. 

I am completely unaware of how you see or feel about the same thing unless you tell me about it.

So things involving consciousness in a live brain is internal and cannot be accessed by others. Only the concerned person has to tell others about it.

In this context, when a person undergoes a serious head injury, identifying how much aware he/she is about the surroundings is very challenging.

With the help of medical tools and advancements, doctors can only identify things to a certain level.

But gaining a level of deeper understanding in order to take some tough decisions about the person’s survival and medical support is still challenging.

When a person undergoes a serious head injury he/she can be in any of the following three states pertaining to consciousness

• Coma – where the person is unable to stay awake and be aware. In this case, the person will require breathing support.
• Vegetative state – The person will be awake, but they won’t show any behaviours of awareness.
• Minimally conscious state – where the person shows signs of minimal consciousness.

The activities of the brain are due to the communication between the neurons. 

When a particular region of the brain is active (pertaining to a particular activity or a state of awareness), that region requires more oxygen and hence more blood supply.

This change can be traced via fMRI through which we can measure the activity of the brain and identify how the neurons communicate.

However, identifying the source of consciousness is not that easy. And some attempts have been made to identify the same via mapping techniques.

With this technique scientists will inject dye into the neurons and map their activity.

However it is very tedious to map all the connections of even a single neuron.

Christof Koch and his team have identified a new mapping technique that makes it easier for scientists to trace and map neurons.

They have made it easier to identify the Claustrum which is a thin sheet of cells found in the brain that is believed to be the center of consciousness.

Koch has also identified three giant neurons that form the major connections of the Claustrum. 

These three neurons are connected to most of the outer parts of the brain that are responsible for receiving sensory information and driving behaviours.

Hence Koch believes that Claustrum could be the residing place of consciousness since the three giant neurons coordinate inputs and outputs.

However Rafael Yuste, a neurobiologist refuses to accept this claim even though he appreciates the mapping technique of Koch.

In a more recent research a team of researchers led by Michael Fox have identified a specific brain stem region and two cortex regions that work together to form consciousness.

The two features of consciousness, arousal and awareness are reportedly being taken care of the brain stem region and the cortex regions respectively, according to this research.

Very recently there has even been a faceoff between the two popular theories of consciousness and results are being compared.

Various other studies are being carried out in this direction.

Ultimately, by understanding consciousness, we would want to wake someone up from coma. Or understand about people’s awareness during and after anaesthesia.

Or have a measure of consciousness that would tell us how conscious a fetus is in the womb. Or understand how genuinely conscious AI is!