Let us look at the human brain itself - it is made of localized areas called lobes, and these lobes “do” things when electrical activity takes place within them. Communication between the lobes is virtually simultaneous, and most of us would like to think that our brains are a seamless whole.
However, each lobe has its own specialization. One lobe processes your thinking and reasoning, another handles input from the five senses, another deals with speech and yet another is your short term memory. These lobes are the conscious part of your mind - it is where you see, hear, think and react to the world outside. Although these lobes are part of the integrated whole, just for discussion purposes and not as a definition, it is useful to group these lobes together as a single unit, and call it “the little brain”.
The rest of the brain deals with everything else from controlling your heart rate to providing emotional responses to holding long term memory. Again, purely for discussion, it is useful to call this subconcious area of your brain “the big brain”, for it really is very much larger than the concious brain.
The technology of fMRI allows doctors to study what is wrong with any one lobe, and researchers to examine what each lobe does. Some of the research simply confirms prior theories, and some gives new insight and explanation.
For example, we now know that the little brain processes about 2,500 bits of data per second, constantly during waking hours, and never varies much from that figure. Big brain processes about 4 billion bits per second, some lobes in constant agitation and others at rest until their functionality is required.
One early discovery explained the experience of deja vu. When a subject loses the short term memory of a sight or sound just after seeing or hearing something, the sound or sight is present in long term memory. That is, the sight or sound entered both short term and long term memory simultaneously, short term dropped it for some reason, and found that long term memory recognized the sight or sound - even though it was being sensed for the very first time. Deja vu really is nothing more than a brain blip.
We now know that the ability to believe in religious ideas is held in three separate lobes, which do other jobs as well. This ability piggy backs on those lobes. That is, there is no special religious belief lobe. (It would have been a very odd god who had the human mind built in such a way that it was impossible to believe in god, and the mechanism neither adds nor subtracts from theology).
The second piece is the temporal lobe. When this lobe is activated, it gives us the ability to empathise with others. It is normally activated by seeing somebody or something, and we sense whatever it is that the person or thing is experiencing. Sometimes it gets activated when no-one is present, and we then sense the presence of that no-one. One cause of such activity is temporal epilepsy - and such epiletics have so many religious experiences that they are considered to be blessed by some cultures. Another cause of such activity is an experimenter providing the lobe with micro-electronic stimulation, and the subjects consistently report religious experience, consistent with the prior teaching of what a religious experience consists of. Christians report sensing the presence of Christ, jews the presence of God, Muslims the presence of Allah, buddhist a state of nivarnah and so on.
The third piece is the Limbic system - several lobes deep in the lowest reaches of the subconcious that provide, among other things, the ability to get ready to have sex, to fight, to flee in fear and so on. One thing we have learned about this particular area is that it is where all Near Death Experience originates - with its hallucinations, ghosts, and light beckoning from the other side of death’s door. Some brave people have had NDEs invoked upon them in labatory settings.
However, outside of such experiments, the strength of NDEs produced by the limbic system are so overpowering, that atheists have been known to become theists after such an event.
We need to look at these three pieces in some more detail - but we have gone far enough for an OP.
Before looking at religious belief itself, I’d like to take your time to look at how the belief system works in general.
The events you conscious mind witness pass into your subconscious instantaneously. The subconscious processing of those events causes emotions, memories etc to be evoked and the results often are passed back to the conscious mind equally instantaneously.
But sometimes the mechanism does not always work properly.
For example, you meet a person and big brain gives you an instant signal that you know this person. May be with some images of shared experience, and so on. Definitely with a signal if this person is friend, foe or an unknown quantity. But the person’s name may escape you. How can that be? Big Brain definitely knows a lot about this person, and must have that name stored somewhere - it is just the ability to get to that memory sometimes stalls. Hypothesis: until modern times, recognizing friend or foe was far more important than remembering names, so our brains are still more geared to the friend/foe recognition than to trivial side issues.
There is a similar effect when you mislay something. Short term memory has no idea where your keys are - someone tells you left them in a particular place - and Big Brain’s instant confirmation makes you slap your head as you say “Doh!” Hypothesis: Big brain sometimes is working to an agenda that does not necessarily match that of little brain. Being at a subconscious level, we have no idea what that agenda is at any one time.
When it comes to what we belief, the sequence is that input to the conscious is processed by the subconscious and the subconscious sends a “true/false/don’t know” sort of signal to the conscious mind.
If I say “Madagascar is a large island in the Indian Ocean” you probably get a “true” signal - even if you have never been to that place in your life. Your subconscious measures the statement, finds it consistent with everything you have been previously been told, and you get the “true” signal.
If I say “Frenchmen live on a large island called France in the middle of the Atlantic” you could get a “false” signal. If the person making the statement is someone you trust, you might get a momentary “don’t know” to see if there is some special meaning, or joke, tied up in a statement clearly at odds with everything you have previously been told about Frenchman and France.
The signal for true/false comes as early in receiving input as possible, and then affects everything that follows thereafter. (This really is very recent research, and may need further work to get it clarified into a predictive phenomena). But it has been shown that if someone makes an early statement that the recipient holds to be false, all the following statements made are scrutinized purely to see where they also fail to be true.
The mechanism is very powerful: a professor of English found that he could dismiss a 27 page essay showing that William Shakespeare might not have been the “real” author of the plays and poems ascribed to him. The professor had published a paper supporting the opposing view - that Shakespeare was the real author. He dismissed his student’s essay out of hand, without further comment, because the wrong year was given in it for King James’ coronation. It mattered not how trivial the error was, it gave his Big Brain all it needed to satisfy its agenda that the submitted essay was wrong.
The sub-conscious acquires its stock of what is true and what is false over a relatively long period of time. Once something is held to be true or false, the belief mechanism is designed to keep that belief intact. When something is moved from being true to being false, or vice versa, the emotion involved with such a switch is very strong. We call it an epiphany.
Once a belief is established, it is very hard to get it changed to something different.
Which is why we will consider next the Jesuit truism “give me the child before he is 7 years old, and I will give you the man”
The lobes in the mind become active from some source of input, and your mind reacts to that stimulation.
For example, there are localized spots in two lobes (the nucleus accumbens and the ventral pallidum) which, when activated, give you a deep sense of pleasure. (Aw, come on, there has to be something in the brain that causes the pleasure sensation). An experiment with Rhesus monkeys (who have similar spots) involved giving them a button, which when pressed, stimulated their pleasure centers. If left to their own devices, those monkeys would have starved themselves to death as they became fixated in a nonstop cycle of pressing their button.
When someone tells you that the purpose of human life is to seek pleasure, it is not impossible for that purpose to be fulfilled by a suitably engineered helmet.
The lobes in the human brain fall into two broad groups: the four lobes that make up your conscious mind, and all the others that make up your subconscious.
A large number of activities in the sub-conscious are reflex conditions that have evolved over time, and exist in us because that reflex in ancient times made our specific ancestors survive in primitive settings.
Being subconscious, we are not aware of the mechanism, but we are aware of the resulting emotion. Public speaking today is often difficult because our successful ancestors fled when surrounded by eyes, and survived. We have a built in reflex to want to flee when surrounded by the eyes of an audience.
Our personality is not inherited - it is a mix of life time experiences reacting with the underlying reflexes. And in acquiring our personality, we acquire our belief system.
There is constant feed back from those we trust as infants (infants who have trust in elders tended to live longer in primitive times, so we also have a built in trust during our infancy). This feedback influences our personality, and as a side effect, our belief system.
Some beliefs rapidly become self-evident through proof: pain is unpleasant and avoiding it is worthwhile.
Some beliefs become self-evident through repetition: if you are bad you will go to hell.
And some through reflexes giving us internal input-response relations. When I stroke a pet cat, it purrs and that gives me a pleasurable sensation. Therefore it is nice to stroke a pet cat.
Now, there was a relevant experiment that used human volunteers. It involved a helmet that stimulates the subject’s temporal lobe.
The temporal lobe’s prime purpose is to give us feelings of empathy with others - it meant that humans could work in packs a long time ago, and as teams nowadays.
When there is no one present, stimulation of the lobe causes the person to emphasize with no-one, and through a process known as agenticity, create some sort of “being” to account for the presence felt.
The device became to be known as “the God helmet”. It was placed on the subject’s head, the button was pressed, and the subject reported a sensation that was consistent with the subject’s core religious attitude.
It was found that the stimulation of a theist’s temporal lobe produced the presence of the relevant god, of a Buddhist led to a heightened oneness with the universe, and atheists reported a warm and fuzzy feeling that they couldn’t quite pin down.
To understand religious belief mechanisms properly, we need to tie to this phenomena those of the Limbic system and the three lobes that carry religious conviction. Then we shall be able to decide if religion is a by-product of stray neurological activity, or the way a God “tickles” lobes to confirm his presence to the believer.
I was once in the triage ward of a hospital. I was waiting for surgery to deal with an internal burst blood vessel. In the early hours of the morning, my blood pressure caused an alarm to sound, and suddenly my bed was surrounded by several nurses and a doctor, doing all sorts of presumably coordinated activity. One nurse smiled at me, stuck a syringe in my arm and said “You are going to be ok” A few seconds later, I went to sleep, and when I woke up, all had been put good, and I was discharged a couple of days later.
Now - something very strange happened in the period between the needle jab and falling asleep.
I was suddenly aware that I was in the presence of an invisible (to me) entity that had an intellect vastly superior to my own. What is more, I instinctively “knew” that this being was totally aware of every single detail of my entire life.
When I was discharged, you might be curious as to why did I not run to church? Well, there was in my way of thinking a serious fault in what this superior being had done - or rather not done. Why had it arrived at that particular moment, and then simply watched as an idle bystander? Why no communication? And where was he or it all the rest of my life? This did not seem at all rational. And I found no solace in the catchall “God moves in mysterious ways”.
I later came across a paper published by Dr R. Joseph. His research material showed that activation of the amygdala, hippocampus, and temporal lobe are responsible for religious, spiritual, and mystical trance-like states, dreaming, astral projection, near death and out-of-body experience, and the “hallucination” of ghosts, demons, angels, and gods.
These lobes are not part of the four bits that make up the conscious part of the brain. When stimulus in the subconscious turns on the images visible to the conscious, the conscious part of the brain has no idea where those images are coming from. And the conscious is absolutely certain that the images are not self induced.
More than one F-84 pilot flying at night, through a cone-of-silence, reported on landing safely that during the scariest part of the flight, they had hallucinated that they were sitting on the wing of their jet fighters, watching themselves fly the airplane. This was originally thought to be a consequence of spatial disorientation, but is now seen to be a result of limbic stimulation caused by the extreme anxiety of flying solo at night in life threatening circumstances.
In short, when the limbic system is activated the subject has strong religious experience, when the temporal lobe is activated when no one is present, the subject has a mild religious experience, and when the conscious part of the mind becomes aware of the subconscious part, the subject invariably reports being in the presence of an invisible all knowing being who has total knowledge of the subject’s life.
These three responses has a causal effect in that three other lobes of the brain may then hold a belief in a deity, either for the first time, or to reinforce an existing belief.
A side effect of the three lobes holding the belief, is that whenever input is heard or seen that challenges that belief, the conscious brain looks for any reason whatsoever in order to be able to discount the input.
The same thing happens with non-believers - they are also constantly looking for any reason possible to discount any input that might disprove their non-belief. We all inherit the same systems.
The limbic system, the temporal lobe and mind expansion can be triggered by stress, drug, illness, random internal neural activity, external electro-magnetic activity, input from any of the five senses and, not proven but included for the sake of completeness, a deity activating these components as part of his divine will.
So - you look at a starry night, a newborn child, a perfect rose, a portrait of Christ - whatever - and the sheer majesty of the emotion evoked from what you see or feel causes the temporal lobe to activate. You could become convinced you are in the presence of god, whose presence now explains the mystery of what you are seeing.
The only thing you have to resolve is whether that temporal stimulation is natural or supernatural.
In my case, I became convinced it was natural.