By Yusuf Lenfest
Think of the last few times you’ve had a very lifelike dream. Running, reading, or having conversations with others, are all activities that might happen during a particularly vivid dream. But would this be considered consciousness? Surely being in a state of sleep is not the same as being in a waking state; but if you are able to communicate, to attend a lecture, perhaps even to give a lecture whilst you sleep, what does this mean in terms of your brain’s activity? Very deep in the sleep cycle, a person may not respond immediately to touch or sound or any other sensory stimulus. That is, they may not wake up, though it cannot be ruled out that an external stimulus might influence the sub-conscious mind and hence their dream. We’ve all had the experience of hearing an alarm “in our dream” which is really our real alarm, yet our mind re-interprets it and incorporates it into our dream until we regain consciousness, i.e., wake up. What if you couldn’t wake up from your unconscious state? And if so, what would this mean for how your brain processes your thoughts? In effect, what would it mean for your lived reality if you could only live in your mind?
Beyond being a fun thought experiment, these may be some very relevant questions now that doctors have treated a vegetative-state patient with an experimental therapy leading him to regain partial consciousness.
It was reported yesterday in National Geographic, Popular Science, the Guardian, and elsewhere that a 35-year-old man who had been in a persistent vegetative state (PVS) for 15 years has shown signs of consciousness after receiving a pioneering therapy involving nerve stimulation. The French researchers reported their findings to the journal Current Biology. Led by Angela Sirigu, a cognitive neuroscientist and director of the Institut des Sciences Cognitives Marc Jeannerod in Lyon, France, a team of clinicians tried an experimental form of therapy called vagus nerve stimulation (VNS) which involves implanting a device into the chest designed to stimulate the vagus nerve. It works by giving off miniscule electrical shocks to the vagus nerve, a critical brain signal that interfaces with parasympathetic control of the heart, lungs, and digestive tract.
So again, what does it mean to be conscious?