How Vegetative Is “Vegetative” Life?

Science Fields

For long the convention in neurosciences was that after staying in a coma for several weeks, people would either die or pass into a state of suspended animation popularly dubbed “vegetative  state”  with no sign of consciousness.  Lately, however,  experiments  have shown that such a state  of completely shut down  consciousness is not true for many of the patients hanging on to life in such a “vegetative” state. The results of some experiments which caused ripples in the world of neurosciences have shown that about 40% of patients believed to be in vegetative state, partly or totally preserve their consciousness , but owing to heavy damage to brain regions that control movements , they are unable to communicate. In neurosciences language, this condition is dubbed being “locked in”.

But after the presence of this locked in consciousness was established, the debate had turned on the best  technique to unlock the barriers and communicate with patients.  In an experiment he conducted with a 23-year-old woman  in vegetative state in 2006, neuroscientist Adrian Owen of  Western Ontario University in Canada, told the woman to imagine she was playing tennis as he inspected  her brain activity, using functional Magnetic Resonance Imaging  (fMRI) technology. The images showed that the woman established communication by  carrying out the instruction.

The fMRI technique basically monitors  the  flow of blood in the brain. Since mental processes  involve a lot of oxygen consumption in activated brain areas,  the patterns tell which brain regions receive the highest amounts of  oxygen-carrying blood. But  as the fMRI technique failed to detect signs of consciousness  in some other experiments, questions were raised about the reliability of the technique. 

In another experiment Owen and his team conducted in 2011, 16 patients with heavy brain damage diagnosed to be in vegetative state were asked to open and shut their right hands and move toes on their right feet. The team established the presence of locked in consciousness in three of the patients, this time with portable electroencephalography  (EEG) devices  at  their bedsides. 

In the above picture you can see the EEG image of a  patient in vegetative state told to imagine playing tennis (middle) is similar to that of a healthy person (right), while another remains unresponsive (left). 

Meanwhile, in a study published in The Annals of Neurology on October 24, neurologist Nicholas Schiff of the Weill Cornell School of Medicine and his team studied the EEG patterns of 44 patients with heavy brain damage and concluded that four of them, although not showing any response to physical stimuli, had EEG patterns similar to those of healthy controls.

In yet another  study co-authored  by Owen, EEG records of 32 patients with brain damage were subjected to a complex mathematical analysis to see which brain parts were working together. The results showed that EEG patterns of three of the patients were similar to those of  healthy people. Then the fMRI technique involving the tennis play  showed  that  all three were conscious and could communicate with the researchers.

In a meeting bringing together over a hundred neuroscientists, neurologists, philosophers and ethicists at the premises of New York University, participants debated methods that could be used in future to protect  brain-danaged people from faulty  diagnosis. The middle road on which Owen ve Schiff could agree emerged as the establishment of the consciousness of patients with cheap and tested EEG technology instead of the expensive and at times unreliable fMRI, which could be used subsequently on those who pass the EEG test  to monitor their brain activities and to thry to establish contact.


  • 1. “An Easy Consciousness Test?”, Science, 31 Octobre 2014
  • 2. “Bedside detection of awareness in the vegetative state: a cohort study”, http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2811%2961224-5/abstract