Patrick McNamara in Aeon:
The medical literature abounds with descriptions of creative bursts following infusion of dopamine-enhancing drugs such as l-dopa (levodopa), used to treat Parkinson’s Disease (PD). Bipolar illness, which sends sufferers into prolonged bouts of dopamine-fuelled mania followed by devastating spells of depressive illness, can sometimes produce work of amazing virtuosity during the manic phase. Often these individuals refuse to take anti-dopamine drugs that can prevent the manic episodes precisely because they value the creative activity of which they are capable during these altered states.
Hallucinogenic drugs such as Psilocybin and LSD, which indirectly stimulate dopamine activity in the brain’s frontal lobes, can produce religious experience even in the avowedly non-religious. These hallucinogens produce vivid imagery, sometimes along with near psychotic breaks or intense spiritual experience, all tied to stimulation of dopamine receptors on neurons in the limbic system, the seat of emotion located in the midbrain, and in the prefrontal cortex, the upper brain that is the centre of complex thought.
Given all these fascinating correlations, sometime after the attack on the twin towers in New York City, I began to hypothesise that dopamine might provide a simple explanation for the paradoxical god effect. When dopamine in the limbic and prefrontal regions of the brain was high, but not too high, it would produce the ability to entertain unusual ideas and associations, leading to heightened creativity, inspired leadership and profound religious experience. When dopamine was too high, however, it would produce mental illness in genetically vulnerable individuals. In those who had been religious before, fanaticism could be the result.
While pursuing these ideas, I had a lucky break during routine office hours at the VA (Veterans Administration) Boston Healthcare System, where I regularly treat US veterans. I was doing a routine neuropsychological examination of a tall, distinguished elderly man with Parkinson’s Disease. This man was a decorated Second World War veteran and obviously intelligent. He had made his living as a consulting engineer but had slowly withdrawn from the working world as his symptoms progressed. His withdrawal was selective: he did not quit everything, his wife explained. ‘Just social parts of his work, some physical stuff and unfortunately his private religious devotions.’
When I asked what she meant by ‘devotions’ she replied that he used to pray and read his Bible all the time, but since the onset of the disease he had done so less and less. When I asked the patient himself about his religious interests, he replied that they seemed to have vanished.
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