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2001 Third Web Report
Belief in God has long been held to be a superstition by the scientific community as the existence of such a higher power cannot be demonstrated through objective observation. While science is unable to prove whether or not God is real, the field of neurotheology has instead posed a new question that we can find answers to: is there activity in the brain specific to religious experience? Can science in fact shed light on Thoreau's question?
Through the use of brain imaging technology, Dr. Andrew Newberg has conducted research in an attempt to find answers to these questions. The participants in his study were Buddhists well-versed in meditation. Newberg used a SPECT (single photon emission computed tomography) camera to make an image of the brain of an individual at the moment he reaches the climax of meditation. Such a picture would enable us to look at the brain as it "experiences God."
The "peak" of meditation is clearly a subjective state, with each individual attaining it in different manners and having different time requirements. However, the sensation and meaning behind this moment is consistent among all who reach it. 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).
As the river flowing east and west
Merge in the sea and become one with it,
Forgetting that they were ever separate rivers,
So do all creatures lose their separateness
When they merge at last . . . (Newberg 6-7)
Newberg first took baseline images of the brains of the meditators to use as a standard for comparison (Newberg 5). It was important that these scans of the brain be taken while the subjects were at rest so that brain activity while one is simply relaxed could be differentiated from brain activity while one is having a spiritual experience. The baseline scans showed an "even distribution of activity throughout the brain," characterized by a large amount of activity in the posterior, superior parietal lobe and a moderate amount in the prefrontal cortex (Newberg 4).1
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). Such changes in activity levels demonstrated that something was going on in the brain in terms of spiritual experience. The next step was to look at what these particular parts of the brain do. Studies of damage suffered to a region of the brain have enabled us to draw conclusions about its role by observing loss of function.
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 (Newberg 28). It responds to proprioceptive stimuli, most importantly the movement of limbs. The region of the lobe in the right hemisphere creates the perception of the matrix through which we move.
Several studies allowed us to come to such conclusions about the parietal lobe. The first involved several Italians who suffered damage to the right side of the parietal lobe (Austin 246) (also Grobstein 5/3/01). A neurologist conducted a simple experiment wherein he asked the patients to describe from memory the piazza of their city as they stood at particular vantage points. The descriptions were normal except for the fact that the patients did not report any buildings that would stand to the left of them from any of the vantage points. Based on their responses, the doctor concluded that damage to this area leads to a disturbance of one's spatial perception. Another study involved a woman who suffered damage to both the left and right sides of the posterior superior parietal lobe. She was unable to use proprioceptive signals in order to position her body in space and to judge the location of objects in space (Stark 482).
The prefrontal cortex, the other area of the brain seen to undergo radical changes in activity, has been dubbed the "attention association area" and can be broken down into several parts (Newberg 93). The medial area gives an individual a sense of personal drive and allows him to plan future actions. Damage to this area results in a loss of motivation to the extent that individuals do not have the initiative to act on their thoughts; in effect, they are unable to accomplish anything that requires an effort on their part (Austin 255). Such observations have led scientists to call this area the seat of the personal will (Newberg 29). The dorsolateral area allows an individual to concentrate on a given task or object by sorting out extraneous sensory inputs (Newberg 30). Damage suffered to this area causes an individual to become easily distractible (Austin 256).
An experiment involving subjects counting either out loud or to themselves reveals the context in which the prefrontal cortex functions (Newberg 30). When one counts out loud, the motor areas of the brain are shown to be activated in a brain scan (signaling the activity of the tongue, lips, and mouth). When one counts to oneself - - an activity that requires great concentration - - the prefrontal cortex is stimulated; this indicates the frontal lobe's particular importance when motor activity is not involved.
We can now analyze the description of the peak experience in terms of these known functions of the posterior, superior parietal lobe and the prefrontal cortex.
The sensation of "the absorption of the self into something larger" can be attributed to the decrease in activity of the posterior, superior parietal lobe (Newberg 7). A lack of stimulation of the left lobe would result in an individual's loss of the sense of self. Because his physical boundaries would no longer be defined, he would feel connected with his surroundings. A lack of stimulation of the right lobe would bolster the individual's feeling of unity with the world as the brain would no longer be creating the perception of a physical space. We have found a correlation between the subjective descriptions of meditators and brain function.
The increase in activity of the prefrontal cortex can be attributed to the process by which meditators reach their peak. The "active approach" of meditation requires that the subject focus all attention on a thought or object (Newberg 120). Such a task would increase the activity in both the dorsolateral and medial areas of the prefrontal cortex. The dorsolateral area allows the subject to concentrate on a thought or object. In addition, it may exclude any superfluous sensory input from reaching the I-function and thus enable his concentration to intensify. The medial area lends the subject a sense of motivation to achieve his goal, i.e., the peak. Such concentration would ultimately result in the peak, whose characteristics we have now correlated with the posterior, superior parietal lobe.
While the connection to an increase in activity of the prefrontal cortex is easy to comprehend as a meditator would be strongly focusing attention on a thought or object, it is more difficult to understand why the activity of the posterior, superior parietal lobe would decrease. Newberg has proposed a theory that the hippocampus, in connection with the thalamus, acts as a "kind of floodgate, regulating the flow of neural input between various regions of the brain" (Newberg 87). In terms of the "active approach" of meditation described above, the great increase in the functioning of the prefrontal cortex would cause the hippocampus to cut off neuronal information to the posterior, superior parietal lobe - - a process he calls deafferentation (Newberg 121). While this pathway would lead to the results we have observed in the SPECT scan, there is little evidence for such a model. Further studies would have to be performed in order to determine the hippocampus' possible role in the regulation of neural flow. In addition, we would have to examine what areas would continue to receive input and what areas would be cut off were this model to be plausible. Newberg offers no suggestion as to why stimuli would be blocked to the posterior, superior parietal lobe in particular.
In addition to his studies of the spiritual experiences of meditators, Newberg also looked at the brains of Franciscan nuns as they engaged in prayer. The SPECT scans revealed similar data about changes in the activity levels of the posterior, superior parietal lobe and the prefrontal cortex (Newberg 7). The nuns, however, described the peak of prayer in a slightly different manner, citing that they feel a "tangible sense of the closeness of God and a mingling with Him" (ibid). The analogous brain scans of the Buddhist meditators and Franciscan nuns suggest that religious experience - - in terms of neurobiology - - transcends religion. It appears that the differences in described experience are due to the application of subjective religious beliefs to the objective neurobiological phenomena by a person's I-function.
Newberg's work demonstrates that there appears to be specific brain activity associated with religious experience. Perhaps we have been able to identify "whence it is that light comes into the soul." However, we have only just begun to put together the pieces of the puzzle, and a great deal of research lies ahead of us. The SPECT scans are static images of the brain at just one moment frozen in time. In order to better understand the brain activity behind religious experience, we must examine neural patterns as they occur during the entirety of meditation/prayer and not just at its peak. Future technology may allow us to do so. We must also consider that the SPECT scans look only at one part of the brain - - the neocortex. Because the brain is a highly complex, interconnected structure, it is imperative that parts of the brain outside of the neocortex be examined in order to determine their possible roles. Analysis of the activity of such other areas of the brain may either bolster or weaken the argument that spirituality can be correlated with brain function.
While we have concluded that there is specific brain activity correlated with religious experience, such findings do not bring insight as to whether or not God is a reality. Is God simply a fantasy created by the brain? Or does God in fact exist, implying that the specific brain activity we have observed is our way of experiencing Him? It is difficult for neuroscience to find an answer to these questions, largely because the brain creates the reality that we perceive, and we therefore do not know what is in fact "real." Our brains sort through the raw stimuli they receive from the world, organize the information, and present our I-functions with what we call "reality." In an effort to create a working reality, our brains often selectively alter information such as in the lateral inhibition network of the optical lobe (which throws out certain visual cues) or the fact that the brain invents part of our visual field in order to account for the blindspot. In effect, we can never know what is truly "real." If God does in fact exist, it is only through our brains that we can experience Him - - through our auditory centers to hear his voice, through our visual centers to see his image, through our cognitive centers to understand Him (Newberg 37).
As long as our brains are arranged the way they are, as long
as our minds are capable of sensing this deeper reality, spirituality
will continue to shape the human experience, and God, however
we define that majestic, mysterious concept, will not go away (Newberg 172).
Newberg set out to demonstrate that "mystical experience is biologically, observably, and scientifically real" (Newberg 7), and he has succeeded in doing so. Although his research cannot prove whether or not God exists, it does lay to rest the long-held misconception that spiritual experience is the result of either emotional distress, delusion, or a pathological state (Newberg 100).3 He asserts that spirituality is the product of "sound, healthy minds coherently reacting to perceptions that in neurobiological terms are absolutely real" (Newberg 100). His research has also been important in demonstrating that the neurobiology of spiritual experience is virtually identical, regardless of theological subjectivity. This uniformity leads us to believe that spiritual experience may have a biological function. Perhaps the lowered blood pressure and superior mental health associated with religious people indicate that the brain's mechanism to allow for religious experience was selected for to improve the survival of man.
As Newberg eloquently concludes, "neurology can reconcile the rift between science and religion, by showing them to be powerful but incomplete pathways to the same ultimate reality" (Newberg 168-9).
Journal of Consciousness Studies. Volume 7, No. 11/12 (2000)
Newberg, Andrew and Eugene d'Aquili. Why God Won't Go Away: Brain Science and the Biology of Belief. New York: Ballantine Books, 2001.
Starks, Marianna. "Impairment of an Egocentric Map of Locations: Implications for Perception and Action." Cognitive Neuropsychology. Vol. 13, 1996, p.481-523
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1 Newberg defined "activity" as an increase in blood flow. A point that might challenge the validity of the analysis of the SPECT scans is the fact that an increase in blood flow does not always indicate an increase in excitation of neurons. An increase in blood flow could instead indicate an increase in inhibition (Newberg 175). Such a finding would alter the interpretation of the results of the scan.
2 Note: The use of the string was not considered to be a disturbance because the subjects were expert meditators (Newberg 173).
3 For example, the American Psychiatric Association classified "strong religious belief" as a mental disorder until 1994 (Newberg 130).