Consciousness and Anesthesia

Consciousness and Anesthesia

            Although scientists still do not fully understand how anesthesia works, anesthesia is still an extremely useful tool to study consciousness. In Maggie Koerth-Baker’s The New York Times article What Anesthesia Can Teach Us About Consciousness, consciousness and the effects of anesthesia are discussed. Daniel Bor, in his book The Ravenous Brain: How the New Science of Consciousness Explains Our Insatiable Search for Meaning, explores consciousness in great detail.

            Koerth-Baker discusses how anesthesia, for about 0.13 percent of patients, keeps patients conscious and able to remember pain and even things their doctors said during medical procedures. A big issue stems from the fact that consciousness cannot be directly measured; doctors cannot be entirely sure if patients are fully unconscious from the anesthesia. The current method of testing consciousness involves recording certain types of brain waves and responses to pain. A way to improve this method, as discussed by Koerth-Baker, is to measure the changes in brain function of a patient as the anesthesia begins to take effect. Neuroscientists call this phenomena neural correlates of consciousness.

            Koerth-Baker explains that no one part of the brain is the center of our consciousness. Bor expands on this idea and explores consciousness psychologically and by examining the neural features of consciousness.

On the psychological side, our awareness seems to be highly connected to consciousness. Bor explains that the output of awareness results from one’s working memory. The working memory holds only about four pieces of information at a time. Bor concludes that the working memory is a main area of human consciousness.

Bor spends a great deal of time exploring the prefrontal parietal network. This area of the brain is highly associated with working memory and attention. Also, the prefrontal parietal network is activated by any task that humans perform. Consciousness seems very much related with the prefrontal parietal network. According to Bor, consciousness seems to start with awareness and ends in the prefrontal parietal network, where a person will have an experience.

Koerth-Baker discusses that a measure of consciousness should be a measure of how the brain takes in and interprets information. According to the article, some argue that the connection between brain regions is consciousness. Koerth-Baker goes on to explain that in a conscious brain, there is high activity between sensory areas and the high level information processing areas. George Mashour, an anesthesiology professor at the University of Michigan Medical School, performed a study that showed that under three different classes of anesthesia, the activity between sensory areas and information processing areas in the brain is undetectable. From this study, Koerth-Baker suggests that a measure of this activity in the brain could help the unlucky 0.13 percent of patients who undergo surgeries while still being conscious.

Link to article: http://www.nytimes.com/2013/12/15/magazine/what-anesthesia-can-teach-us-about-consciousness.html?pagewanted=all&module=Search&mabReward=relbias%3Aw&_r=0

References:

Bor, D. (2012). The ravenous brain: How the new science of consciousness explains our insatiable search for meaning. New York: Basic Books.

Koerth-Baker, M. (2013, December 10). What Anesthesia Can Teach Us About Consciousness. The New York Times.