I watched the BBC video (the 15:50-26:20 clip). The question I am blogging about is "Can we know whether someone still has conscious awareness?"
In the clip, a man was being tested to see whether we could see conscious awareness while he was under anesthesia. The level of consciousness was being measured by giving him a command and seeing if he responds with a conscious decision. This allows us to see if he is consciously aware. In this particular study, the command was to imagine you are playing a game of tennis. They gave this command to him while he was completely conscious and watched his brain activity. Then they tested him again after he had received anesthesia and was heading towards a "uninhibited state of delirium," as he worded it. The study showed that, although his brain activity was slower and a bit more relaxed, he was showing the same amount of brain activity than when he was completely conscious. The brain scanner showed that his activity was the same as when he was conscious, however, his reactions and activity was slower, more relaxed, and slurred. This study was basically measuring conscious awareness and acting as a "consciousometer." This study was also done before with a woman who was actually in a vegetative state. They measured her conscious awareness at different times while she was sick. Each time, her brain activity came out as the same, just more relaxed or slower. One important thing to know about brain activity and consciousness is brain parts need to be active in order to stay conscious. By giving the command of "imagine yourself playing a game of tennis," it keeps your brain active and allows you to stay conscious and concentrated.