A poll last year found 85% of Americans believe that God created the universe. In Nigeria, 98% claimed always to have believed in God, while nine out of 10 Indonesians said they would die for their religious beliefs. Polls have their faults, but if the figures are even remotely right, they illustrate the prevalence of faith in the modern world.
Faith has long been a puzzle for science, and it’s no surprise why. By definition, faith demands belief without a need for supporting evidence, a concept that could not be more opposed to the principles of scientific inquiry. In the eyes of the scientist, an absence of evidence reduces belief to a hunch. It places the assumptions at the heart of many religions on very rocky ground.
So why do so many people believe? And why has belief proved so resilient as scientific progress unravels the mysteries of plagues, floods, earthquakes and our understanding of the universe? By injecting nuns with radioactive chemicals, by scanning the brains of people with epilepsy and studying naughty children, scientists are now working out why. When the evidence is pieced together, it seems that evolution prepared what society later moulded: a brain to believe.
One factor in the development of religious belief was the rapid expansion of our brains as we emerged as a species, says Todd Murphy, a behavioural neuroscientist at Laurentian University in Canada. As the frontal and temporal lobes grew larger, our ability to extrapolate into the future and form memories developed. ”When this happened, we acquired some dramatic cognitive skills. For example, we could see a dead body and see ourselves in that position one day,” he says. That awareness of impending death prompted questions: Why are we here? What happens when we die? Answers were needed.
Religion would have played another important role as human societies developed. By providing contexts for a moral code, religious beliefs encouraged bonding within groups, which in turn bolstered the group’s chances of survival, says Pascal Boyer, an anthropologist turned psychologist at Washington University in St Louis, Missouri.
”What I find … plausible is that rather than religion itself offering any advantage in evolutionary terms, it’s a byproduct of other cognitive capacities we evolved, which did have advantages,” says Boyer.
Psychological tests Boyer has run on children go some way to proving our natural tendency to believe. ”If you look at three- to five-year-olds, when they do something naughty, they have an intuition that everyone knows they’ve been naughty, regardless of whether they have seen or heard what they’ve done. It’s a false belief, but it’s good preparation for belief in an entity that is moral and knows everything.”
According to Boyer, the persistence of belief into adulthood is at least in part down to a presumption. ”When you’re in a belief system, it’s not that you stop asking questions, it’s that they become irrelevant. In belief systems, you tend to enter this strange state where you start thinking there must be something to it because everybody around you is committed to it.”
While some continue to tease out the reasons for the emergence of religion and its persistent appeal, others are delving into the neuroscience of belief in the hope of finding a biological basis for religious experience.
At the University of California in San Diego, neuroscientist VS Ramachandran noticed that a number of patients with a condition called temporal lobe epilepsy reported having deeply moving religious experiences. ”They’d tell me they felt a presence or suddenly felt they got the meaning of the whole cosmos,” says Ramachandran. The feelings always came during seizures, even if the seizures were so mild, they could only be detected by sensitive electroencephalograms.
Ramachandran decided to test a couple of patients using the galvanic skin response. Two electrodes are used to measure tiny changes in the skin’s electrical conductivity. In most people, conductivity goes up when they are shown violent or sexual pictures, or similarly loaded words, but Ramachandran found that patients with temporal lobe epilepsy responded very differently. Violent and sexual words produced not a flicker, but religious icons and the word ”God” evoked a big response.
With only two patients involved in the study, Ramachandran says it is impossible to draw any conclusions, but if the results stand up to future testing, it might indicate that seizures in the temporal lobe strengthen certain neural pathways connected to the amygdala, which, among other tasks, helps us focus on what is significant while allowing us to ignore the trivial. ”If those pathways all strengthen indiscriminately, everything and anything acquires a deep significance, and when that happens, it starts resembling a religious experience,” he says.
At the University of Pennsylvania, radiologist Andrew Newberg has cast a wider net. By injecting radioactive tracers into the veins of nuns, Buddhists and others, he has constructed brain maps that show how practices affect neural processing.
”What comes out is there’s a complex network in the brain and depending on what you do, it is activated in different ways,” says Newberg. ”If someone does Tibetan Buddhist meditation, they’ll activate certain parts of their brain, but if you have a nun praying they’ll activate slightly different parts.”
Newberg uncovered the neural processing behind the religious experience of ”oneness” with the universe. Blood flow drops off in the parietal lobe, a brain structure that helps us orient ourselves by giving us a sense of ourselves. ”What seems to be happening is that as you block sensory information getting into the parietal lobe, it keeps trying to give you a sense of self, but it no longer has the information to do so. If that happens completely, you might get this absolute feeling of oneness.”
Newberg has been criticised for his investigations into the essence of spiritual experience. ”Some people want me to say whether God is there or not, but these experiments can’t answer that. If I scan a nun and she has the experience of being in the presence of God, I can tell you what’s going on in her brain, but I can’t tell you whether or not God is there.”
Intriguingly, many scientists, while stressing that they have set out to explore religion rather than disprove its basis, say that no matter what they uncover about the nature of spiritual experiences, mass religious belief will continue.
”For two centuries, there’s been competition between churches and in the free market of religion, the products get better and better as people want different things,” says Boyer. ”Will science be the death of religion? As neuroscience, it’s interesting to see how brains can create very strange states of consciousness, but in terms of threatening religion, I think it’ll have absolutely no effect.” — Â