Physicians have been perplexed by the inability to determine if a person that is in a “vegetative state” has any true consciousness. A new method of comparative analysis of electroencephalograms developed by Dr. Srivas Chennu and Dr. Tristan Bekinschtein from the University of Cambridge and colleagues from the United States and Canada has created a tool that can determine if a person in a vegetative state retains some level of conscious awareness.
The researchers compared the brain waves of people in a vegetative state to each other and to the brain waves of normal people. The alpha wave of people in a vegetative state showed the least activity. The measure of alpha wave activity and the activity produced in alpha wave activated regions of the brain was found to be the most important measure of a person’s level of consciousness if the person is in a vegetative state. The delta and theta brain waves of people in a vegetative state were identical regardless of the condition that caused the person to become unresponsive.
The researchers also found that a few people that are considered to be in a vegetative state respond mentally to images measured by functional neuroimaging. Functional neuroimaging can measure the electrical equivalent of brain images in a person’s brain. The response has never been seen before in people that were once considered to be “brain dead”. The response is limited to only a few percent of people that are in a vegetative state.
The discovery is proposed as a method of determining which people have a potential to recover from injury or disease that has produced a vegetative state. The equipment that is needed to do the testing is readily available in most hospitals. This discovery could eliminate the political and “moral” uproar that accompanied the Terri Schaivo case that lasted almost 15 years. Living wills may have to be rewritten to include this new test procedure.
