University of Cambridge

How conscious are you? It seems like an unanswerable question. But new research from the University of Cambridge claims to be able to measure exactly how aware you are of your own existence.

The technique, developed by neuroscientist Srivas Chennu, combines classic EEGs with graph theory, a form of maths. With two simple pieces of equipment -- a cap covered in electrodes and a box that measures patterns of electrical activity, Chennu can measure the brain's "signature", which represents the ways in which neurons, and neural networks, are firing.


Being conscious is about more than simply being awake -- it's also made up of "noticing and experiencing", Chennu says. "When someone is conscious, there are patterns of synchronised neural activity racing across the brain, that can be detected using EEG and quantified using our software."

The technology is portable, and Chennu hopes that it could be used as a "bedside device" for doctors treating patients in vegetative states, or who have brain traumas caused by injuries or strokes. It could be used to help provide patients with better care, or even offer insights to help wake a patient from prolonged states of partial arousal.

Patients who show signs of consciousness, for example, may be kept on a life support machine for longer than a patient who does not. In trials of the device, the team observed two patients -- one who showed high levels of consciousness, depicted in images as a huge, colourful mohican, and one who did not. The first patient eventually woke up -- the second didn't.

Chennu and his team will now undertake a three year long experiment, observing and treating 50 patients with brain damage.

"Medical advances mean that we are identifying subtypes of brain injury and moving away from 'one size fits all' to more-targeted treatment specific for an individual's needs," said Chennu in a statement. "The question that fascinates us is what type of consciousness do patients have?" "Moreover, we think that the measurement of brain networks will provide clinically useful information that could help with therapeutics for a larger majority of patients, irrespective of whether they are able to demonstrate hidden consciousness."