Religion is a human universal and in looking for the origins of religion, some researchers are looking at brain disorders. One of the ways that neuroscientists discover the workings of the brain is by learning what happens when it doesn’t work well. Closely associated with the origins of some religious traditions, particularly the revealed religions, are schizophrenia and epilepsy.
Hallucinations play an important role in many religions. These can range from the trance states obtained in shamanic ceremonies, to speaking in tongues in Christian churches, to the visions of religious prophets which resulted in established religious traditions. In his book The Demon-Haunted World: Science as a Candle in the Dark, Carl Sagan writes:
“Whatever their neurological and molecular antecedents, hallucinations feel real. They are sought out in many cultures, and considered a sign of spiritual enlightenment.”
Carl Sagan also reports:
“There are countless instances in the world’s religions where patriarchs, prophets, or saviors repair themselves to desert or mountain and, assisted by hunger and sensory deprivation, encounter gods or demons.”
Hallucinations are common and are found throughout the world. Hallucinations are not necessarily a sign of mental illness, although brain disorders can intensify the experience. In his book In Gods We Trust, Scott Atran writes:
“Previous neurobiological studies of religion have focused on tracking participants’ neurophysiological responses during episodes of religious experience and recording individual patterns of trance, vision, revelation, and the like. This has favored comparison of religious experience with temporal lobe brain patterns during epileptic seizures and acute schizophrenic episodes.” (italic in original)
Schizophrenia is a condition in which a person will see patterns all the time, giving all of the patterns equal weight for relevance. In other words, they are unable to weed out unlikely patterns. People with schizophrenia have distorted perceptions of reality—they are unable to distinguish what is real from what is imaginary.
In his book Nature via Nurture: Genes, Experience, and What Makes Us Human, Matt Ridley reports:
“Schizophrenics experience their thoughts as loud. In the old days, this was called hearing voices, but today it usually takes the form of believing, for instance, that the CIA has implanted a device inside one’s head. Schizophrenics also imagine that others can read their minds, and they are apt to personalize every event, so that they think a television news broadcaster is sending them a secret message. Paranoid schizophrenics develop baroque conspiracy theories and as a result are likely to refuse treatment.”
In addition to seeing patterns, schizophrenics are also likely to assign some kind of agency to both the patterns they perceive and their actions in response to these patterns. In her book The Human Brain, Rita Carter reports:
“Some attribute their own actions to the intentions of others, claiming they are being ‘controlled’ by outside forces; others, that they ‘cause’ events unconnected with their own actions, such as moving the sun.”
In his book Thought: A Very Short Introduction, Tim Bayne puts it this way:
“Among the ‘first rank’ symptoms of schizophrenia is the delusion that one’s actions are under the control of other agents (the delusion of alien control) and the delusion that thoughts are being inserted into one’s mind by other agents (the delusion of thought insertion.)”
In some instances, schizophrenics report hearing the voice of a god and this can result in a religious revelation if other people believe the account.
With regard to the impact of hallucinations on religion, Scott Atran writes:
“In every society, the auditory and visual hallucinations that our medical establishment associates with certain forms of temporal lobe epilepsy and schizophrenia often take a religious color. They become the ‘voices’ and ‘visions’ of personal revelation for the subjects themselves and, depending on the society, they may become the charge of local religion as well.”
Scott Atran also writes:
“Accounts of visual and auditory hallucinations among some of history’s leading religious converts and mystics intimate possible temporal lobe epilepsy.”
Auditory hallucinations—i.e. hearing voices—is a common characteristic of schizophrenia. Functional MRI scans during auditory hallucinations show activity in the right hemisphere of the brain rather than in the left hemisphere which is normally associated with language. This is probably why the voices are often attributed to external sources.
With regard to brain imaging studies, Scott Atran writes:
“Brain imaging shows heightened electrical stimulation and increased blood flow to this area of the brain during bouts of epileptic seizure, schizophrenic hallucination, speaking in tongues, trance, and deep meditation and prayer. But whereas schizophrenic-like episodes of epilepsy and schizophrenic hallucinations appear to be associated with decreased activity in the frontal cortices, meditation and prayer seemed to be associated with increased activity.”
As a brain disorder, schizophrenia is found in all cultures, all ethnic groups, and appears to occur among them at about the same rate. This implies that schizophrenia, and the religions which have been inspired by it, has a physical, probably genetic, basis. Matt Ridley writes:
“It implies perhaps that the mutations that predispose some human beings to schizophrenia are ancient, having occurred before the ancestors of all non-Africans left Africa and fanned out across the world. Since being schizophrenic is hardly conducive to survival, let alone to successful parenthood, in a Stone Age world, this universality is puzzling: why have the genetic mutations not died out?”
At the present time, no single gene has been found which causes schizophrenia, but many genes seem to influence susceptibility to it.
Human Origins
Human Origins: Religion and the brain
Human Origins: Cooperation
Human Origins: Making Spoken Language Possible
Human Origins: Language is innate
Human Origins: Sexual Dimorphism
Human Origins: Fossil Evidence
Human Origins: Homo habilis
Human Origins: Homo rudolfensis