Around 85% of the global population identifies as religious. Decades of work in the social sciences have found that religious or spiritual beliefs and practices can improve people’s health and well-being; increase social cohesion, empathy and altruistic behaviour; and protect people against cognitive decline or substance abuse1. But also, throughout history, religion and spirituality have amplified conflict, polarization and oppression2–4.

Despite the manifest importance of faith as an influencer of human behaviour, neuroscientists have tended to steer clear of studying how people’s beliefs affect their brains and vice versa. This includes investigation of the effects of beliefs in supernatural agents or miracles, practices around worship or prayer and participation in rituals.

Such avoidance probably stems in part from centuries of powerful religious institutions resisting scrutiny and interrogation. But researchers and funders are also fearful that any investigation of religiosity or spirituality could be seen either as promoting a particular religion, or as flat-out unscientific.

In 2021, researchers at the Public Health, Religion, and Spirituality Network searched the records of more than 2.5 million project proposals submitted to the US National Institutes of Health since 1985. They noted that spirituality-related terms appeared in only 0.05% of abstracts and 0.006% of titles, whereas religion-related words appeared in 0.09% of abstracts and 0.009% of titles (see go.nature.com/3jtez5q).

To better understand the human brain — as well as religiosity and spirituality and their effects on human life — this needs to change. We call on scholars from diverse disciplines to help establish a rigorous field: the neuroscience of religion. Our goal is not to debunk or promote religion or spirituality, but to understand the neural mechanisms underlying their effects.

What’s known

Over the past century, but especially during the past two decades, researchers in anthropology, psychology, religious studies and other fields have investigated and defined the diverse beliefs, behaviours and social systems associated with religious and spiritual practices around the globe. In the late 1960s, for instance, the US anthropologist George Murdock documented rituals directed at supernatural agents, or beliefs in magical powers or supernatural agents in 168 cultures5. Such works provide knowledge and tools for neuroscientists.

Take, for example, the challenge of defining a particular belief or practice as being religious or spiritual. Psychologists have been using the Mystical Experiences Questionnaire (MEQ) for around 55 years. Updated in 20126, it was originally developed in 1969 by the US psychiatrist Walter Pahnke, who used a classification of mystical experiences derived from thousands of religious narratives mainly collected between 1900 and 1950. Using the MEQ, researchers note whether self-reports of an experience mention a positive mood or ‘blissful state’; inner peace or connectedness with others or with nature; a transformed sense of self; and so on. Each factor is scored according to certain criteria. Experiences with a high score are deemed religious or spiritual.

Participants bathe in ice-cold water during a Shinto ritual at Teppozu Inari Shrine on in Tokyo, Japan.

Participants in an ice-cold-water Shinto ritual hope to purify their bodies and souls.Credit: Tomohiro Ohsumi/Getty

The MEQ and other psychological metrics can be used with brain-imaging techniques that allow neuroscientists to map the neural activity associated with all sorts of cognitive, social and emotional processes. Such methods include functional magnetic resonance imaging (fMRI) and neuromodulation approaches that transiently alter the brain’s electrical activity — for instance, through electro-magnetic stimulation.

Only a few investigators using these and related techniques have made religion or spirituality the main focus of their research. But replicable findings are starting to emerge.

During the 1990s, mainstream media picked up on reports of a ‘God spot’ in one region of the temporal lobe. The reports were based on observations that religiosity was sometimes drastically heightened in some people with symptoms of temporal-lobe epilepsy. Since then, however, brain-imaging studies have shown — unsurprisingly — that religious and spiritual experiences and practices (such as prayer) are associated with the upregulation and downregulation of neural activity in multiple regions in the brain (see Fig. 1 of ref. 7). These regions overlap extensively with brain networks that are modulated during mindfulness meditation8. They also overlap with those that are associated with multiple capabilities in social cognition. This includes the ability to infer people’s mental states and understand how those states might influence their behaviour (theory of mind); the ability to distinguish between self and other, including an imagined improved or enlightened self; and the ability to monitor who belongs in a group and who does not9.

The effects of brain lesions — such as those resulting from a stroke — provide more evidence that neural networks involved in self-awareness and social cognition are linked with religious or spiritual beliefs and practices. In one study, 24 people reported that they experienced increased feelings of connectedness with other people and with nature (self-transcendence) after the removal of brain tumours in a region called the temporoparietal cortex10. In the same study, 24 people who had tumours removed from a different brain region — the frontotemporal cortex — didn’t report such experiences.

Other analyses using fMRI indicate that people who regularly engage in spiritual or religious practices have measurable differences in their brains.

In a 2023 study, researchers analysed neuroimaging and behavioural data from around 40,000 participants in the UK Biobank cohort11. They found that connectivity in and between brain regions involved in self-reflection and in emotion regulation was greater in people who regularly engage in religious practices than in those who regularly engage in sports or in those who regularly engage in social activities. These variations in connectivity patterns between the three groups — such as in a group of brain regions called the default mode network (DMN) — are strictly correlative. Whether religious experience contributes to certain connectivity patterns, or whether people who have certain connectivity patterns are predisposed to affiliate with religious groups, is an interesting topic for future research.

Brain-imaging studies conducted over the past decade indicate that psychedelic drugs modulate activity in several specific brain regions. These are the regions that are also modulated during religious and spiritual experiences or practices, and that are associated with capabilities in social cognition12. Most psychedelic drugs are known to affect neural pathways that are modulated by serotonin. The data suggest that altering the activity of circuits that are normally regulated by serotonin signalling, including those in the DMN, can affect people’s sense of self, their feelings of connectedness with others and with nature, and the likelihood that they will report an encounter with a supernatural agent12,13.

In other studies, researchers have reported dose-dependent effects of psychedelic drugs, with higher doses yielding more participants reporting what they describe as religious or spiritual experiences. This supports the idea that serotonergic modulation of brain circuits underlies these particular effects of psychedelics13. Also, a systematic review of papers on the reported effects of psychedelics published during 2015–20 indicates that many people have what they describe as religious or spiritual experiences after taking these drugs, which can have long-lasting effects on their behaviour14.

These studies on psychedelics have involved small numbers of participants so far (around 5–20 per study) owing to the difficulty — and cost — of obtaining regulatory approval for the drugs and providing the level of psychological support and evaluation needed. But the findings are supported by the results of informal surveys of several thousand respondents who have experience with psychedelics15,16. In one survey, most of the participants reported having encounters with supernatural entities, or reported that their experience had transformed their sense of self. In the same survey, around 28% of the participants reported that they were atheist before taking the drug15. Only 10% said that they were atheist afterwards.

Digging deeper

Such fascinating neuroscience-based findings have emerged despite there being very few researchers working on the problem. In our view, a much richer understanding could be obtained — not just through more researchers engaging with the topic and more funders supporting the work, but through investigators using newly available tools.

Artificial intelligence (AI), for example, could be used to identify brain-activity patterns associated with thinking about religious or spiritual concepts, or the performance of a religious task or practice. Large language models (LLMs) and other computational tools that analyse vast swathes of text could be used to systematically examine subjective reports of religious and spiritual experiences — regardless of whether those experiences occurred in natural environments, or through the controlled use of pharmacological agents or other interventions.

A group of people perform a traditional dance from the State of Oaxaca, Mexico, in the San Bernardino Cathedral in Xochimilco, Mexico City, on Christmas Eve.

People in Xochimilco, Mexico, celebrating Niñopa, the most venerated image of the Child Jesus in the region.Credit: Gerardo Vieyra/NurPhoto via Getty

Virtual reality (VR) offers one way to create experiences in a controlled setting that might be similar to those considered to be religious or spiritual in the real world. Earlier this year, for example, psychologists exposed 48 people to perceptual experiences in VR. Participants were simultaneously given visual and audio cues and the guided VR experience took place in a beautiful, realistic environment that included awe-inspiring surreal elements. They could also interact with other participants through avatars.

Participants in a control condition were given the same auditory script but their eyes were covered to eliminate any visual or social cues. Remarkably, 40% of participants who were exposed to the test condition reported having mystical experiences (measured by MEQ scores) after only 10 minutes of exposure. Only 6% of the same participants reported having mystical experiences in the control condition17.

We are not maintaining that VR or psychedelic-induced mystical experiences are equivalent to religious experiences. Nor do we think that experiments involving such interventions could ever adjudicate religious statements, such as that a supernatural agent exists. But if VR techniques and pharmacological manipulations can evoke experiences in the laboratory that have much in common with religious or spiritual experiences in the real world, brain-imaging or brain-stimulation techniques could be used to map the neural activity associated with such experiences. Likewise, systematically altering the environment could identify the conditions under which certain individuals report experiencing an encounter with a supernatural agent.

A changing world

Some neuroscientists are beginning to collaborate with religious scholars worldwide, for instance in the Cognitive Neuroscience of Religious Cognition project, a three-year effort that two of us (J.G. and P.M.) are involved in. But to realize the promise of this emerging field, hundreds of cognitive neuroscientists and biomedical researchers need to engage with these questions, and more.

Many people use meditation or other practices (which might or might not be spiritual) to help them deal with pain and addiction8. A better understanding of the brain processes associated with religiosity and spirituality might provide extra tools for treating pain and addiction — for religious and non-religious people alike. Likewise, by investing in the neuroscience of religion, researchers might be able to get a better handle on what (if any) alterations happen in people’s brains in the rare instances when religious belief turns to radicalized action or sectarian hatred, or when healthy religious community bonds veer into cult-like pathology.

A neuroscientific interrogation of religiosity and spirituality is crucial to understanding the human brain — and human life. And now is the time to expand it. In many countries, polls are indicating major shifts in the number of people defining themselves as religious, spiritual, both or neither. Increasing numbers of people in high-income countries are leaving traditional religious affiliations and identifying themselves as spiritual, but not religious. In low-income countries, religious traditions are remaining strong or even expanding. Meanwhile, more people around the globe classed as Generation Z (those born between 1997 and 2012) seem to be embracing highly traditional religious affiliations, such as traditional Catholicism or Judaism.

Neuroscientists are well placed to identify the ways in which — for good or for ill — these shifts are affecting people’s brains and how those changes might, in turn, shape people’s responses to emerging social, cultural and ecological challenges.