Neurotheology: How Science can Enlighten us About Spirituality

In the previous chapter, we considered how myths have an impact on the human brain and the important relationship between the brain and religious beliefs. However, myths refer primarily to the stories we tell to better understand the world. Myths hit us on a cognitive and an emotional level. But is it possible that they have an even greater impact throughout the entire body and brain? In religion, myths are elaborated within the context of rituals. Rituals are perhaps the most powerful behaviors that humans, in fact almost all animals, can participate in. Moreover, while religion has certainly made great use of ritual, rituals are also found in virtually every facet of human life.

As we discussed in chapter 6, the relationship between ritual and the brain plays a fundamental role in understanding neurotheology. Rituals probably began in the context of mating. Mating rituals are found throughout the animal kingdom and are essential for bringing together two animals of the same species to produce offspring. The goal of the mating ritual was to signal readiness for mating, identify an appropriate mate, and allow two animals to physically come together. In animals, as in humans, mating rituals have many different elements that incorporate visual displays, sounds, smells, and rhythmic movements. This is why a common place for humans to find a mate is at a dance. There are music, lights, smells, and lots of rhythm. These stimuli drive the brain to achieve the goals of the ritual. Since the primary goal of the mating ritual is to lose yourself and become one with another, it makes sense that religious and spiritual rituals would co-opt this process. After all, the goal of the religious ritual is to become one with another—usually the group, God, or the universe. Thus, religious rituals incorporate many, if not all, of the same elements.

The anthropologist Alan Fiske has identified the following as important components of religious rituals¹:

When considered in the context of ancient mating rituals, these elements make sense. If the ritual is done correctly, mating occurs. If the ritual is done incorrectly, mating fails. The specific elements not only drive the autonomic and limbic areas to peak states but also help with the clear identification of the mating animals. These rituals likely began as part of the mating process and then became incorporated into more and more complex human behaviors, culminating in religious and spiritual rituals.

Why are rituals so powerful? Rituals seem to affect us on many different levels. Most importantly, rituals bring our entire being into the mythic story. We don’t just think about it; we experience it fully. And through this experience, we understand and connect with the world and our beliefs.

Pascal Boyer provides some background on why rituals are so important and have such a powerful effect.2 He describes rituals as having three important components: a sense of urgency, social effects, and use of the supernatural. The sense of urgency refers to the mind-grabbing power of the ritual. It signifies that something important is embedded in the ritual and is likely related to the visceral effects on the autonomic nervous system and the limbic system. The social effects have to do with the ability of the ritual to bring people together. This might be in the form of a wedding or perhaps a larger group ritual such as communion or a bar mitzvah that binds people as part of the process.³ This effect ties in well with the effect of ritual on the parietal lobe’s social areas. The supernatural participation is likely related to the sense of the presence of something greater than oneself, particularly something with a mind or agency. This is probably related to changes in the parietal and frontal lobes.

A sense of surrender, possibly also related to changes in the frontal lobes, seems to be an aspect of many rituals. According to Patrick McNamara, rituals tend to reduce people’s sense of agency and volition.⁴ During a ritual, they are more likely to give themselves over to the group or to God. He also refers to this as a “decentering process.” Fiske refers to ritual as a “cultural coordination device,” which brings people together within a common cultural system.⁵ This concept might also support the notion of costly signaling, a potential theory for the evolutionary basis of religion. Rituals can carry a high cost to perform, especially when there are elements that require personal pain. However, the cost of performing the rituals helps ensure that all participants are buying into the group and its belief systems.

Ritual are also a kind of tool or technology, especially since most of the elements are prescribed by someone else.6 And it is important to use the technology appropriately to accomplish the goal of the ritual. Human rituals should probably be considered a “morally neutral technology,” which, depending on the myth in which they are embedded, can either promote or minimize particular aspects of a society, including aggressive behavior. The basic way this happens is through the powerful unifying experience that arises. Rituals likely drive the autonomic nervous system, and then the brain, to experience a deep sense of oneness or connectedness with something else: another animal, God, or the universe. Thus, if a ritual defines the unitary experience that the myth generates as applying only to a limited group, then what one ends up with is the unification of just that group. Feelings of aggression within that group are usually reduced since everyone feels a sense of coming together around a central idea. However, this may serve only to emphasize the special cohesiveness of the group vis a vis other groups.⁷ The result may be an increase in aggression against other groups, particularly those that follow other myths and rituals. The myth and its embodying ritual may apply to all members of a religion, a nation state, an ideology, all of humanity, or all of reality. Even if a small group engages a myth and ritual that espouse that all humans are one, or are part of a universal consciousness, then the members of the group would feel connected to all other humans. As the scope of the unitary experience broadens, the degree of outward aggressive behavior decreases.

The states produced during ceremonial and religious rituals seem to overlap with some of the unitary states generated by various meditative practices, which we will consider later. However, it is probably not too strong a statement to say that human rituals, including religious ones, provide the “common person” access to the mystical or transcendent.

So how do rituals actually work? Their structure seems to be relatively similar across all types and kinds of rituals. The structure and process of rituals over time ultimately lead to unique changes in the brains of the participants. The brain–ritual connection has important neurotheological implications.

Rituals are filled with prescribed or patterned movements.14 This means that specific actions or movements must be performed as part of the ritual. We see this in many animal species that perform various movements with their bodies as a way of identifying themselves as a member of the same species, to signal their readiness for mating, and to help select the best mate. In more primitive animals, these rituals can be fairly rigid with very specific movements required throughout the process. In higher animals, such as mammals and primates, rituals can be far more flexible as the brain itself is more complex. Even in higher animals, however, there are certain elements that typically are required, but the specific order and the exactness of those movements are not necessarily the same each time the ritual is performed.

Perhaps the most essential element of all rituals is the rhythmic aspect. All rituals have rhythmic and repetitive elements that can occur both within a given individual, as well as in concert with other individuals.¹⁵ Sometimes the rhythmic elements are with one other member of a group or species such as in mating rituals. Sometimes the rhythmic elements involve many individuals. The rhythmic effect of wolves howling can get an entire pack into a howling frenzy. They seem to feed off each other’s vocalizations as they ramp up the volume and the intensity. The same is true of humans; for example, rituals that involve dance can synchronize the participants’ behaviors and responses, eventually leading to a strong sense of interpersonal connection.¹⁶

Since the rhythms in rituals are perceived through the senses, rhythms tend to drive brain functions from the “bottom up.” Thus, the rhythm of ritual may be related to music or movements of the body, which drive certain lower areas of the nervous system, ultimately affecting the higher areas of the brain. The first area of the nervous system affected by ritual is the autonomic nervous system. As described in earlier chapters, the autonomic nervous system is composed of two arms: the sympathetic and the parasympathetic. The sympathetic nervous system functions as our arousal system, whereas the parasympathetic nervous system functions as our calming system. Rituals with either rapid or slow rhythms are able to affect one arm of the autonomic nervous system or the other. Very slow rhythms, such as in Gregorian chants, or slow, swaying body movements can increase activity in the parasympathetic nervous system, the calming system. In driving the parasympathetic nervous system, the effects of a ritual are felt throughout the body. The heart rate and respiration slow, energy use decreases, and the body enters a state of calm. Alternatively, very rapid rituals, which can include rapid drumming or frenzied Sufi dancing, drive the sympathetic nervous system. As the sympathetic nervous system turns on, we feel that effect throughout the body with an increase in heart and respiration rates and an overall sense of arousal.

The two arms of the autonomic nervous system typically work in an antagonistic way. When the sympathetic nervous system is activated, the parasympathetic nervous system tends to be suppressed, and when the parasympathetic nervous system is activated, the sympathetic nervous system tends to be suppressed.17 In rituals, activation of the parasympathetic nervous system would theoretically produce a greater sense of calm or even bliss throughout the body of the participant. A very rapid ritual would likely drive the sympathetic nervous system to create a heightened state of arousal and alertness while suppressing a sense of calm.

On an everyday level, we use rapid rituals during certain types of events such as sporting events. When you’re ready to go out and play an intense football game, you want your sympathetic nervous system to be cranked up as high as possible. Rituals with rapid drumming from the marching band, heavy metal rock music, and fans chanting loudly all stimulate the players’ sympathetic nervous system to get ready to play. On the other hand, if you’re trying to get ready for bed, soft, soothing music, dim lighting, and pleasant scents help to augment activity in the parasympathetic nervous system to allow the body to relax and fall asleep.

There is evidence that while the two arms of the autonomic nervous system mutually inhibit each other under normal circumstances, there are times when an intense driving of one side leads to a breakthrough or idiosyncratic turning on of the other side.¹⁸ This complex relationship between the arousal and quiescent functions of the autonomic nervous system led two scholars, Ernst Gellhorn and W. F. Kieley, to suggest an autonomic nervous system model of religious experiences, particularly mystical ones.¹⁹ They argued that shifts in the autonomic nervous system were responsible for the compelling sense of quiescence or excitement during rituals.

Eugene d’Aquili and I expanded on this model in our approach to these experiences. For example, in a ritual that drives the sympathetic nervous system to a high level of intensity, as the arousal state becomes significantly elevated, the person might experience a breakthrough of the parasympathetic nervous system. The result is that in the midst of highly frenzied activity, the person has a brief experience of profound calm. This may explain how whirling dervishes can increase their physical activity (and sympathetic activity) until they finally collapse with a breakthrough of the parasympathetic side and an experience of profound bliss. Conversely, one might expect that during a prolonged meditation practice that drives the parasympathetic nervous system to create a powerful sense of bliss and calm, at some point a person might experience a breakthrough of the sympathetic nervous system and a profound sense of arousal or ecstasy.

Several research studies have found interesting autonomic nervous system activity during religious and spiritual practices by measuring heart rate variability. Most have shown that meditation practices that elicit relaxation also reduce heart rate. However, a small number of studies have now demonstrated that some of the more active practices, such as loving-kindness meditation, may actually increase the heart rate. But another way of looking at the effects of ritual on the body focuses not on what the heart rate is at a particular time, but how it varies over time. Under normal circumstances, the sympathetic and parasympathetic nervous systems maintain a fine-tuned balance of your heart rate. It does not vary much from moment to moment. During certain practices, particularly meditation, however, heart rate may vary significantly.20 The variation in a person’s heart rate during meditation is greater than when sitting or lying still or performing other activities. The implication of this research is that there may be a kind of simultaneous push-and-pull occurring between the sympathetic and parasympathetic nervous systems. The greater variability in heart rate is a supporting piece of data regarding the relationship of the autonomic nervous system to rituals like meditation practices. This can be extrapolated to other types of religious and spiritual practices that also result in an increase in heart rate variability on top of an overall relative increase or decrease in the heart rate itself. Thus, we might expect that during slow, rhythmic chanting, the heart rate would decrease but the heart rate variability would increase. Conversely, during frenzied religious activity, both the heart rate and heart rate variability would likely increase.

From this perspective, as alluded to earlier, we might expect four different autonomic states to be associated with religious and spiritual rituals or practices:

We might also consider a fifth possibility in which both the sympathetic and parasympathetic arms of the autonomic nervous system are highly activated, resulting in a state of intense, simultaneous bliss and ecstasy, perhaps related to mystical experiences, which we will consider in chapter 14. These five possible patterns represent nodal points along a continuum of experience. It is also important to note that these do not necessarily reflect a hierarchy of experiences, but rather distinctions in autonomic nervous system balance or tuning during different rituals. Thus, we cannot claim that one state is “better” than another, only that they differ from each other.

We have mentioned that rituals typically represent a bottom-up activation of the nervous system. If rituals begin by altering activity in the autonomic nervous system, we should be able to understand how such changes ultimately become linked to higher-level brain functions. The primary controlling structure of the autonomic nervous system in the brain is the hypothalamus. The hypothalamus helps regulate our basic body functions, such as heart rate, blood pressure, respiration, and digestion, through its influence on the autonomic nervous system. Thus, the pattern of responses that occurs in the autonomic nervous system likely has an effect on hypothalamic function. It should be noted that top-down processes, perhaps like meditation, likewise affect the autonomic nervous system via the influence of the higher cortical areas on the hypothalamus. However, for rituals, the autonomic nervous system drives the hypothalamus, which subsequently affects higher brain structures.

Eventually, rituals activate not only the hypothalamus, thalamus, and limbic system, but through connections with the cortex, cause changes in the higher centers of the brain. Thus, a ritual can be associated with various thoughts, memories, and other ideas that become elaborated as part of a larger mythic structure. McNamara refers to this process as “historical consciousness”; through this process, a person becomes more deeply connected to his or her group, culture, or religion.21 Rituals can drive many different areas of the brain to stimulate experiences associated with various abstract or mythic elements.

It is also possible that changes in the limbic system and the ability to regulate neural information eventually result in altered activity in the parietal lobe, which is involved in our sense of oneness or unity and a loss of the sense of self. This would further foster a sense of community among the participants of a ritual. This sense of unity could also be applied to the mythic story, or even to God or the universe. In religious rituals, people frequently refer to a sense of being connected with God in a total body-and-mind way. In addition, mythic elements and stories can drive our emotional centers and ultimately our autonomic nervous system. Again, this reciprocal interplay between the higher centers of the cortex, limbic system, thalamus, hypothalamus, and autonomic nervous system is crucial to the power of rituals and myths and ultimately to religious experience.

Another aspect of ritual is the identification of specific ideas or images. As previously mentioned, Antonio Damasio has proposed the somatic marker hypothesis, which states that certain areas of the human brain, such as the amygdala, light up when a person sees something of great importance.22 The amygdala activity identifies the importance of the object and then inscribes our experience of it deeply into the memory areas of the brain. Rituals are often associated with certain marked movements or the presence of sacred objects at specific times. For example, in the midst of deep religious singing, the image of a cross might denote a specific idea about the impact of Jesus Christ’s life on that individual. Another aspect could be certain movements such as a specific bow or prostration that occurs in the midst of a ritual, which, through amygdala activation, are identified as important. The marked events that occur during a ritual help further establish the link between the ideas contained in religious myths as experienced through the ritual process.

A variety of sensory phenomena are also frequently part of rituals. We have already considered how our senses might contribute to the overall experience of ritual. For example, researchers have shown that repetitive auditory or visual stimuli can drive neural rhythms in the brain and eventually produce an intensely pleasurable, ineffable experience in humans.²³ Further, these repetitive stimuli can bring about intense simultaneous activity in the sympathetic and parasympathetic nervous systems.²⁴

While Pascal Boyer describes specific patterns of unique movements, sensory stimuli, and other specified elements, he goes further to suggest that many of the behaviors in ritual resemble obsessive–compulsive behaviors rather than normal behaviors.25 The relationship between ritual and obsessive–compulsive disorder may help us understand some of the neurophysiological processes involved in both. It may be that obsessive–compulsive disorder is the expression of rituals to an abnormal and intrusive level. As discussed in chapter 8, it is well known that many disorders result from the aberrant functioning of normal brain processes. Emotions of excitement or sadness are important for adapting to the world, but if they become extreme, we may experience mania or depression. It is interesting that a common finding among people with obsessive–compulsive disorder is heightened activity in a structure called the caudate nucleus. This area is a highly dopaminergic area and seems to be involved in both emotions (via the limbic system) and behaviors (via the frontal lobes). The increased activity of the caudate associated with obsessive–compulsive disorder appears to be related to the repeated, compulsive behaviors. Thus, dopamine and the caudate nucleus are probably part of the overall brain system involved with ritual. Rituals are important for making important connections to the world, but they can go awry. In addition, rituals can be co-opted for evil purposes. Rituals have contributed to great hatred and anger. For example, the Nazis used rituals in a highly effective manner, having midnight book burnings and specific rituals for birth, marriage, and death, all with the goal of indoctrinating people into the Nazi belief system.

Rituals also can be related to the instillation or removal of cognitive processes. For example, initiation rites help incorporate a person into the group. But sometimes, practices are antithetical to knowledge, preventing questioning that might disrupt group cohesion. This allows people a sense of greater understanding regarding social interactions or interactions between themselves and the rest of the world. In fact, as Boyer suggests, rituals give people a greater understanding of social relationships, which are frequently difficult to figure out. He further argues that rituals, and their prescribed components, are “snares for thought” because they “activate special systems in the mental basement.”²⁶

Using neurotheology, we can now consider the specific structures of the brain and autonomic nervous system involved in ritual. The autonomic nervous system, the limbic system, and the parietal lobes are all involved. The various elements of a ritual activate these brain areas and ultimately connect the ritual to a given mythic story or concept.

We mentioned in the previous chapter that myths typically present a problem as a pair of opposites that need to be resolved. The problem presented in a myth is generally not just a cognitive one, but a deeply felt existential problem of the society or person. Resolution usually requires a powerful sense of unity or reconciliation of the opposites. Since rituals typically produce powerful unitary experiences, enacting the myth in ritual form allows for a highly effective personal way of resolving the mythic problem. When the ritual enactment works, the sense of resolution of the mythic problem is vividly experienced by the participants, and the resolution of the otherwise irreconcilable opposites becomes an experienced fact.

Examples of mythic solutions to the God–human opposition include a solar hero, a Christ figure, or a divine kingship. Similarly, good and evil might be unified into a single entity such as “Absolute Good,” which encompasses both good and evil. From the neuropsychological perspective, these resolutions may be caused by a shift in cognitive processes from a binary or reductionist approach to a more holistic way of thinking. It might also be argued that this shift is also seen in brain activity going from the dominant (typically the left) hemisphere to the nondominant (typically the right) hemisphere and involving the parietal lobes, which contribute to a sense of unity and holism.27 Such experiences involving a sudden insight have been shown to result in strong emotional responses.²⁸ This includes the “Eureka” phenomena attributed to Archimedes solving the problem of how to measure the volume of an irregular object by immersing it in water. The story states that Archimedes had a sudden insight when he sat in a bath full of water and watched the water overflow as he sank. By physically becoming the solution, he had a sudden apprehension of the solution. Not only did he have an intellectual insight, but he then went running naked through the town yelling, “Eureka!” (“I’ve got it!”). The important thing about this story is that Archimedes combined a cognitive problem with a physical activity, much as the physical activity of a ritual helps resolve an existential problem.

One recent study of this phenomenon using brain imaging involved presenting a series of problems that required sudden insights to solve.²⁹ In one such task, the test subject is presented with three problem words (pine, crab, sauce) and is tasked with finding a single solution word that can be linked to each of the three problem words (apple: pineapple, crab apple, applesauce). Importantly, the investigators based their analysis not just on solving the problem, but also on whether the test subjects “felt” they had solved the problem with insight. The results demonstrated that the right hemisphere became more active during the insightful solution to the problem.

Religious rituals aim to experientially unite opposites in an effort to achieve some form of understanding or control over what appears to be a completely unknowable and unpredictable universe. The ultimate union of opposites is that of a vulnerable humanity with a powerful, possibly omnipotent, force. Thus, for religious myths and rituals, it would seem that humanity and some “supernatural” power are the ultimate poles of mythic structure. It is this polarity that is the fundamental problem ritual must resolve existentially.

The cognitive–verbal–motor connection is significant when considering the development of ritual behavior in the context of myth. The motor manifestation of cognitive–verbal expression is ordinarily inhibited by the brain. However, it tends to break through in normal individuals when we “talk with our hands.” This may be the case because of the evolutionary advantage we as humans have of using our increased intelligence and cognition to modify outward behaviors. Much of our ability to communicate is not in our words as much as it is in our hands, body postures, and facial expressions.30 The combination of motor activity and verbal expression makes communication much clearer and more powerful.

In a similar way, humans are naturally disposed to act out our myths. However, myths are not acted out using ordinary motor behavior, but via rhythmic motor activity. Humans reach far into the evolutionary past to combine ancient motor behavior with the higher verbal and conceptual brain functions; that is, with myth. Why should we do so? The answer lies in the nature of ritual behavior.

In general, effective ritual can, and usually does, produce the powerful subjective experience of the integration of opposites. During certain meditation and ritual states, logical paradoxes, or the awareness of polar opposites, are presented and ultimately resolved as unified wholes. This experience is coupled with an intensely emotional, blissful, and ecstatic experience. During intense meditative experiences, the experience of the union of opposites is expanded to the total union of self with other. In the unio mystica (mystical union) of the Christian tradition, the experience of the union of opposites, or conjunctio oppositorum, is expanded to the union of the self with God.

Ceremonial ritual, at its most effective, is an incredibly powerful technology whether for good or ill. Further, because of its essentially social nature, it tends to have immeasurably greater social significance than private meditation or contemplation. But meditation and contemplation are rituals that have a unique ability to produce more intense and more extended unitary states compared to the relatively brief flashes generated by ritual. These private practices are solitary experiences that can have immense significance to the individual. Indeed, the significance of meditative states may be of a genuinely transcendent nature, but they are not social experiences, although they may have social consequences.

The intensity of ritual could also be evaluated using current scientific approaches. Our research group has already studied the depth of specific meditation practices that are supposed to result in different levels of experience. We will describe the results in more detail in the next chapter, but one significant finding was that we found clear differences in the brain associated with differences in the subjective depth of the practice.31 Rituals can also induce a variety of experiences, ranging from very mild to very intense. Is it possible to use neuroimaging equipment to determine the difference between a ritual that produces a mild experience and one that induces a much deeper experience.

It is also relevant to explore the differences in rituals across traditions and cultures. On one hand, there are a great deal of similarities between singing rituals in Judaism and Christianity and those in Buddhism and Hinduism. They all involve singing, swaying, and coming together as a group. If we can match up the various elements, it would be interesting to see whether the variations in diverse cultural rituals elicit different responses in the brains of the individuals participating.

Another question I am frequently asked is whether group rituals or individual rituals have a greater impact on the brain. Religions make great use of group rituals, particularly with regard to various sacred services and ceremonies. It is also well known both anecdotally and through several research studies that the effect of a group of individuals on a given participant, especially when performing rituals, can be quite great.32 Some studies have also suggested that the more individuals who participate, the greater the influence on a given individual.³³ However, individual rituals, typically prayer and meditation, can be just as, if not more, powerful than group rituals. Most of the early studies in this area, which will consider in the next chapter, explored the effect of individual rituals on the brain. And there are a variety of changes that appear to occur in the brain during individual rituals. To answer the question of how group rituals compare to individual ones, it would be interesting to study whether a prayer such as the Lord’s Prayer has the same impact when repeated by a single individual versus a group. Listening to the prayer being said by others may synchronize with the prayer said by the individual, resulting in a prominent resonant effect.

Several neuroscientific principles support the impact of group rituals on the brain. For example, drumming rituals appear to help synchronize the brains of different drummers. A recent fMRI study explored the brain activity of eighteen women while drumming in synchrony or out of synchrony with an experimenter.³⁴ The women were also given a sociality test after the drumming activity. The results showed that the caudate nucleus in the basal ganglia was activated during synchronous drumming and is associated with prosocial behaviors. Studies like this, exploring the neurophysiological and social effects of religious and spiritual rituals, may be an important part of future neurotheological investigations.

An important discovery has to do with mirror neurons in the brain. Mirror neurons, which appear primarily in the frontal lobes and in the parietal lobes, which support social functioning, reflect in your brain what another individual is doing.35 If you see somebody raise his or her hand, the mirror neurons in your brain will trigger you to raise your own hand. Whether you actually act out this particular neural process depends on a variety of factors. Typically, we suppress the actual behavior; however, certain actions and behaviors are “contagious,” including yawning and smiling. It is difficult to not smile when somebody is smiling at you. It has been argued that mirror neurons play a prominent role in the effect of group rituals on a given individual.³⁶ Observing other people swaying, singing, or praying elicits a similar kind of response in your own brain, and there is evidence that the brains of various individuals can synchronize or resonate with each other.³⁷ In this way, the rhythms of a given ritual can be transmitted across individuals. Unfortunately, no studies have yet specifically confirmed the sense of inter-individual resonance in a large population; however, it is known that the brains of two people can resonate with each other, especially during effective communication.³⁸

It should also be mentioned that future neuroimaging studies could involve not only the study of basic activation paradigms, but also an exploration of more detailed neurotransmitter changes. Studies could explore the effect of rituals on a variety of neurotransmitter systems including oxytocin, dopamine, and serotonin. It would be fascinating to discover which neurotransmitter system is affected most by rituals. And again, since different rituals appear to have different effects, whether they all will have the same or different effects on specific neurotransmitter systems would also be important to determine. With regard to neurotransmitter systems, there are several ways in which such a study could be designed. Studies could use brain imaging technology to explore whether various neurotransmitter systems are activated during a particular ritual. Alternatively, studies could use a kind of “subtraction” technique in which people are asked to perform a ritual before and after being given a medication that blocks a particular neurotransmitter system to determine whether there is a difference in the experience of the ritual depending on the activation or deactivation of a specific neurotransmitter system.