The nature vs nurture contribution is unknown and probably very hard to assess. Studies with twins indicate some role for nature (genes and inherited innate hard wiring). What culture and life experience can do is alter hard wiring to some unknown extent. The brain partially rewires itself all the time in response to life experiences.
The following shows some of the struggles that science is having in dealing with spirituality and how to describe it and do research on it.
To figure out whether the main empirical question “Is our brain hardwired to believe in and produce God [the producing point of view], or is our brain hardwired to perceive and experience God? [the perceiving point of view]” is answered, this paper presents systematic critical review of the positions, arguments and controversies .... allowing consciousness/mind/spirit and brain/body/matter to be seen as different sides of the same phenomenon, neither reducible to each other. .... A methodological shift from “explanation” to “description” of religious experience is suggested.Thus, based on the reasoning set out above, we can construct the following definition of religious experience: religious experience is the very moment of experiencing of ultimate divine reality or ultimate divine truth, a transcendence of events or universe, timelessness, spacelessness, and divine being and/or union with it in any combination with an accompanied memorable feeling of reality, emotions and thoughts with a religious content. We use the word “religious” instead of “mystic” or “spiritual”, because “religious” in our opinion is a narrower concept and also adds a cultural dimension.
It seems that religious experience was and is a world-wide phenomenon. According to Burkert (1996) in prehistoric times no groups of people lived which had no religious experience (judging by the existence of religion). At the same time, groups existed which have no demonstrated such attributes of human culture as agriculture, clothing, money, laws and writing.Arguments for a “producing” point of viewA “producing” point of view (sometimes it is referred as neuroscientific and/or cognitive) is a reductionistic one and can be summarised as follows: our brain is structured so as to provide us with experiences that make us believe there is a God, but this belief may merely be the result of internal brain activity and our interpretation of it.Argument 1: It has been reported that the intense activation of the frontal and temporal cortices and limbic system, as well as (de)activation of the parietal cortex give rise to religious experience (for the full list of brain areas and structures and for the references, see Table 4). .... The formulation of argument 1 is weak because the findings on which it is based are correlative in nature, and as such, they tell us nothing about the cause-consequence relationships. .... It follows from this brief critical review of the arguments for a “producing” point of view that observed neuroscientific arguments tell us nothing about the true nature of religious experience or God.Arguments for a “perceiving” point of viewThe “perceiving” position (sometimes it is referred as theological) can be summarised as follows: our brains have the capacity to perceive God, and since our brain is designed to attune us to reality, this points to the likelihood that there is a God.Argument 1: If the human brain enables humans to have religious experience, to perceive and believe in God, then it should be a reason for this experience (Joseph 2001). .... Religious experience may co-evolve with any other human phenomenon (for example, deactivation-mediated abstract reasoning, Previc 2006) which increases the survival of the organism. On the other hand, religious experience and practice themselves may have a protective effect on human communities and thus may also increase their survival. However, this reasoning tries to explain how religious experience has been preserved in human evolution but not the reason for the origin of religious experience.
As it follows from critical review of the arguments for both the “producing” and “perceiving” points of view the main empirical question “Is our brain hardwired to believe in and produce God, or is our brain hardwired to perceive God?” remains unanswered.
A 2016 assessment of the state of the art indicates that spirituality is both hard wired and an adaptation. The Brain Blogger wrote:
The question of whether religion has been “hardwired” into our brains or an evolutionary adaptation has been debated for decades, however, more recently we have uncovered scientific underpinning for both possibilities.Barrett equates religion to language acquisition where “we come into this world cognitively prepared for language; our culture and upbringing merely dictate which languages we will be exposed to.” Brain Blogger’s own Dr. Jennifer Gibson discussed how “the brain seems predisposed to a belief in all things spiritual” back in 2008.As the original question remains unanswered, we are early… the neuroscientific study of religious and spiritual phenomena remains in its infancy. There is mounting evidence of a biological correlate to these phenomena, however, this does not necessarily negate an actual spiritual component.
Neurotheology originated from brain-scan studies that revealed specific correlations between certain religious thoughts and localized activated brain areas known as “God Spots.” This relatively young scholarly discipline lacks clear consensus on its definition, ideology, purpose, or prospects for future research. .... God Spot research is poised to move beyond observation to robust hypothesis generation and testing.The field of neurotheology emerged from metabolic brain-scan discoveries, made in a few pioneering laboratories, showing that specific areas of the brain become more metabolically active when people have religious experiences (d’Aquili and Newberg 1999; Newberg et al. 2002; McNamara 2009; Newberg 2010, 2018). Scholars have responded to these findings in various ways, ranging from intrigue, to indifference, and to dismissive labeling of these areas as “God Spots” in the brain.
The field is unsettled. Physical structures in the brain, neural pathways or hard wiring, are believed to be necessary for religious or spiritual experience, but those concepts that are hard to define and pin down. One can be doubtful that a spiritual component outside the brain is involved. But that belief is probably subject to the criticism that it is too reductionist and/or contradicted by sufficient evidence. Maybe so, but I continue to doubt it.