Sunday, October 25, 2009

The sense of "I"

The other night on Irish TV I saw a fascinating show about how the sense of “I” or “me” arises out of the brain. In other words, what happens at the neuronal level that causes us to organize the world as “me” and “not me.” The narrator was a mathematician atheist. He began the discussion with a review of Descartes’ notions of mind-body dualism which attempted, but ultimately failed to answer the question of how a nonmaterial mind could influence a material body, without invoking supernatural explanations. This program was attempting to summarize our current understanding of the mind-body issue by reviewing some current research.

The assumption of most of the research reviewed arises out of the assumption that the sense of “I” arises from the brain. As a result, some of the studies focused on neurological investigations. The first involved cortical stimulation of the brain. MRI scans were done at the same time to describe how electrical impulses flow within the brain. This study showed that, when awake, the area stimulated immediately shows a response, but that other areas of the brain then show electrical activity. This appears to show that in the awake brain, various areas communicate with each other after stimulation and that activity is not limited to just one area. In contrast, when an area is stimulated in the sleeping brain, electrical activity is limited to just the area stimulated. When a person is asleep, and presumably without the sense of “I”, his or her brain functions differently than when awake, when presumably the individual has the sense of “I.”

Another study showed that in one individual, there are neurons that appear to store information of a certain type. The researchers found that a certain bundle of neurons stored material related to Jennifer Anniston. When the individual was shown a picture of Anniston, the neurons fired. When shown a picture of Anniston and Brad Pitt, the neurons did not fire. However, when the subject was shown the letters “Jennifer Anniston”, the neurons again fired. The researcher concluded that neurons were storing the concept “Jennifer Anniston” rather than just her visual image. This seems to indicate that single or bundled neurons act as file folders for concepts. Thus, the neurons could, by extension, contain a concept of “I”.

The final study focused on how visual cues can support the sense of “I.” The experiment involved having a subject wear a visor that contained a video screen, much like those that are used to view movies with a portable video player. The visor blocks out visual input except that which is on the screen. Attached to the visor are two video cameras mounted behind the subject. As a result of this setup, the subject is viewing himself as seen by another person. The subject reported disorientation as a result of the confusion between his predetermined sense of location and the visual cues of being in a different location based on the feeds from the cameras. To compound the confusion, the experimenter placed the video cameras on his head and then walked around. This was even more confusing for the subject, given that he was seated. From the subject’s point of view, his sense of “I” was being disturbed by the incongruous video feed. This study was certainly interesting, but struck me as a bit gimmicky. It did not demonstrate whether the subject would become habituated to the incongruous video cues and thus recover to some degree the sense of “I.”

Like many TV-based summaries of research, this British-made show did not have time to explore all of the limitations of the studies nor the antecedent and subsequent studies that may have shed more light on the phenomenon investigated. The show did show how science can approach the study of how the sense of “I” is created. From the results presented, the mind-body interaction arises out of neuronal activity and sensory input. This seems obvious, but the obvious is not always correct.

One of the problems with this, and other neurological research, is that the studies must use such large and complicated machinery that the process of measuring the phenomenon being studied introduces a certain artificiality that likely influences the results. As technology continues to evolve, more sophisticated and miniaturized equipment may help reduce the influence of the process of measurement on the findings.

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