http://serendip.brynmawr.edu/bb/neuro/neuro01/web3/Farrenkopf.html
At the peak, the subjects indicate that they lose their sense of individual existence and feel inextricably bound with the universe. "There [are] no discrete objects or beings, no sense of space or the passage of time, no line between the self and the rest of the universe" (Newberg 119).
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The subjects then meditated. When they reached the peak, they pulled on a string attached at one end to their finger and at the other to Dr. Newberg.2 This was the cue for Newberg to inject the radioactive tracer into the IV connected to the subject. Because the tracer almost instantly "locks" onto parts of the brain to indicate their activity levels, the SPECT gives a picture of the brain essentially at that peak moment (Newberg 3). The results revealed a marked decrease in the activity of the posterior, superior parietal lobe and a marked increase in the activity of the prefrontal cortex, predominantly on the right side of the brain (Newberg 6).
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It has been concluded that the posterior, superior parietal lobe is involved in both the creation of a three-dimensional sense of self and an individual's ability to navigate through physical space (Journal 216). The region of the lobe in the left hemisphere of the brain allows for a person to conceive of the physical boundaries of his body