People become aware of themselves between the ages of 18-24 months, but what changes for this to happen? We don't just wake up one morning and all of the sudden know that we are ourselves. What part of the brain activates our consciousness? According to the video "BBC Horizon-The Secret You" there is no one part of the brain that holds our consciousness. In fact it is actually a complex process that does this.
According to "The Secret You" it all starts in the Reticular Activating System, which is a group of diffused nerve cells in the brain stem. This sends projections to the relay system known as the Thalamus, which then sends these projections throughout the Cortex. Consciousness is constant activation of the Cortex. So when do we consider someone to be out of consciousness? Do we consider someone to be out of consciousness when they are in a vegetative state? A researcher from "The Secret You" video is finding evidence on the contrary. When people that are in vegetative states were asked to imagine themselves playing a tennis match the same part of their brain was activated as the healthy volunteers who were asked the same question. In a sense they were acknowledging that they were being asked a question and reacting to that question. Does this mean they still have consciousness? Is it wrong then to take someone off life support who can still process in their mind thier surroundings? When should people be considered brain dead or out of consciousness? I am interested in what people have to say on this topic.
Where Does Consciousness Reside In Our Brian?
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I believe that do have consciousness still because their same parts of the cerebrum are still activating. If those are still activating like that of a normal person why not call it even? People should be taken off of life support based on their living will I believe, I don't think it has to do whether they still have "consciousness" or not but on what they want in particular or what the power of attorney says. So this will vary from case to case and it, I'm sure, will effect some more than others based on their own morals.
The question of consciousness is so mind boggling. I agree that there is no one part of the brain that contains the consciousness portion. I think that would be too easy of an answer for such a complex question. An extraordinary question needs to be answered with an extraordinary explanation. One possible theory could be that consciousness resides in the soul. This cannot be explained or tested using science but I guess it is more of a belief or faith statement. I also think you raised a questionable point about when someone is considered conscious. This can be viewed in the field of medicine. When someone’s heart beat has stopped they are considered to be nonliving. However, when someone has no brain waves but still has a heartbeat are they unconscious, or even dead? I think this is a debated topic because no one can know for sure. What makes someone considered dead?
Is being self aware being conscious? I think consciousness is a very hard thing to measure scientifically, because what do you actually measure? An operational definition needs to be made for consciousness to measure it. I heard about the tennis match experiment on a podcast, and they found that some people in vegetative states still had brain activity, while others did not. I think the way they measured this brain activity would be a good way for families of patients in vegetative states to decide if they want to keep the person on life support or not.
This post reminded me of the Terri Schiavo case that was flashed across the media in 2005. After going into full cardiac arrest, Terri suffered severe brain damage. Doctors attempted various therapies, but none were successful and she was diagnosed as being in a vegetative state. Terri Schiavo's husband wanted her feeding tube, the life-prolonging measure, to be removed. However, Terri's parents contended that it should not be removed because she was still conscious. Ultimately, the case went to court and it was ruled that her feeding tube be removed. This case shows how difficult it is to determine what consciousness means and if a person is conscious or not.
As Chapter 3 says, brain death is different from being in a persistent vegetative state. I would say that it is OK to pull the plug on people in vegetative state, if they can never do their activities on their own any time ever. I say this because if the person is a donor and has healthy organs then they could save many lives by giving up their own.
I used saw a video about research of consciousness of infants. Researchers get some babies who are under 18 mouths.. They don't aware themselves in front of a mirror. Also, when people point them and call their name, they don't understand whom people imply. However, After those babies get older, researchers do the same things again. Those babies become interested in the persons in mirror and learn why mirror persons do the same things as them, because mirror persons are themselves. Also, babies are mad about people's pointing.. This example prove the person's self-consciousness.