The unique brain signature of consciousness identified

#1
Consciousness is all about connectivity...

https://www.sciencealert.com/scientists-...sciousness

"Our new study, the product of a collaboration across seven countries, has identified brain signatures that can indicate consciousness without relying on self-report or the need to ask patients to engage in a particular task, and can differentiate between conscious and unconscious patients after brain injury.

When the brain gets severely damaged, for example in a serious traffic accident, people can end up in a coma. This is a state in which you lose your ability to be awake and aware of your surrounding and need mechanical support to breathe.


It typically doesn't last more than a few days. After that, patients sometimes wake up but don't show any evidence of having any awareness of themselves or the world around them – this is known as a "vegetative state".

Another possibility is that they show evidence only of a very minimal awareness – referred to as a minimally conscious state. For most patients, this means that their brain still perceives things but they don't experience them.

However, a small percentage of these patients are indeed conscious but simply unable to produce any behavioural responses.

We used a technique known as functional magnetic resonance imaging (fMRI), which allows us to measure the activity of the brain and the way some regions "communicate" with others.

Specifically, when a brain region is more active, it consumes more oxygen and needs higher blood supply to meet its demands.

We can detect these changes even when the participants are at rest and measure how it varies across regions to create patterns of connectivity across the brain....

...We found two main patterns of communication across regions. One simply reflected physical connections of the brain, such as communication only between pairs of regions that have a direct physical link between them.

This was seen in patients with virtually no conscious experience.

One represented very complex brain-wide dynamic interactions across a set of 42 brain regions that belong to six brain networks with important roles in cognition (see image below). This complex pattern was almost only present in people with some level of consciousness.

Importantly, this complex pattern disappeared when patients were under deep anaesthesia, confirming that our methods were indeed sensitive to the patients' level of consciousness and not their general brain damage or external responsiveness.

Research like this has the potential to lead to an understanding of how objective biomarkers can play a crucial role in medical decision making.

In the future it might be possible to develop ways to externally modulate these conscious signatures and restore some degree of awareness or responsiveness in patients who have lost them, for example by using non-invasive brain stimulation techniques such as transcranial electrical stimulation."


[Image: file-20190206-174887-rhh4xh1.jpg]
Reply
#2
Hopefully it'll rescue some of the supposedly brain-dead that got nixed too early in the past. [Or is it a curse for some of those who never come out of it? Only her comatose dream-world knows for sure.]
Reply




Users browsing this thread: 1 Guest(s)