New Signs of Awareness in Vegetative Patients

We’re one step closer to understanding what goes on in the brains of people in vegetative states.

A vegetative state, or a chronic disorder of consciousness, is the absence of responsiveness and awareness in a patient due to the impairment of the cerebral hemispheres. However, autonomic responses are still happening, such as eye movement and yawning, and the sleep-wake cycle is maintained. But patients do not have an awareness of their surrounding environments, nor can they interact with other people.

A team of scientists at the Department of Clinical Neurosciences at the University of Cambridge used high-density electroencephalography (EEG) to gain an insight into the network of information transfer in the brain between normal controls and people in vegetative states. It was shown that some vegetative patients demonstrated awareness by following commands in neuroimaging tests. The functional neuroimaging showed that they had alpha networks that were well-preserved and similar to those in the healthy controls. This is significant as the alpha network modules have been linked to alertness and attention in the brain.

The importance of this discovery lies in the fact that it will help us understand brain function in such patients. Despite not being able to directly interact with their environments, the patients show brain network mechanisms that support a certain degree of cognitive function and consciousness. Since prognosis tends to be poor for vegetative patients and the treatment available is mainly supportive, this finding can help us improve clinical assessments and identify patients that are aware despite appearing uncommunicative.

http://www.ploscompbiol.org/article/fetchObject.action?uri=info%3Adoi%2F10.1371%2Fjournal.pcbi.1003887&representation=PDF