International scientists looked at the brain signatures of consciousness in healthy adults and compared them to people in a low conscious or vegetative state.
They show that the networks which support awareness in healthy brains are impaired in the those of vegetative patients.
And some comatose patients still have well preserved brain networks, meaning they may still be aware but can’t tell us.
In a study published in the journal PLOS Computational Biology, University of Cambridge researchers Srivas Chennu and Tristan Bekinschtein use electroencephalography to analyse the brains in 32 patients diagnosed as vegetative and minimally conscious.
Some unresponsive vegetative patients (who show signs of hidden awareness by following commands like imagining playing tennis) have well-preserved brain networks that look similar to those of healthy adults.
This research could help identify patients who might be covertly aware despite being unable to tell anyone.
“Being able to detect the recovery of brain networks in patients, alongside or even before they show behavioural signs of improvement, is very promising,” the researchers say.
“However, further work is essential to translate these scientific advances into viable tools that can be reliably used.”