The Neuroscience of Religious Experience is a book by Dr. Patrick McNamara, a professor of neurology at Boston University School of Medicine. This post has some notes from the book.
• A number of investigators suggest that the human sense of Self depends crucially on the anterior temporal and prefrontal cortex.
• Neuroimaging studies (PET and fMRI) of persons performing self-related tasks have demonstrated that self-related processing tasks are associated with activation in the orbital and adjacent medial prefrontal cortex, the anterior cingulate, the dorsomedial prefrontal cortex, the insula, and the posterior cingulate cortex.
• Lesions in right prefrontal and anterior temporal regions virtually always result in syndromes of disinhibition.
• In alien hand syndrome, a patient with damage to the SMA or to the nearby anterior portion of the corpus callosum may experience one of his hands as alien or someone else’s hand.
• Patients with bilateral frontal lobe damage display a pattern of behavior that reflects the now unopposed activity of the parietal lobes. These patients are excessively influenced by the external environment. They are stimulus bound, concrete, socially inappropriate, and display a remarkable inability to grasp context.
• Schizophrenia is associated with limbic, anterior temporal, and prefrontal dysfunction.
• In multiple personality disorder, the takeover or the suppression of the first-order identity occurs relatively rapidly, typically in less than 5 minutes. Most, but not all, patients exhibit either a burst of rapid eye blinking and eye rolling at the beginning of the takeover. There may be dramatic shifts in EEG patterns and in brain activity patterns. Sometimes these alterations in brain activity patterns are even associated with a change in handedness.
• A study involving an exhaustive inventory of religious and spiritual experiences given to 57 temporal lobe epilepsy patients found that 51 percent indicated that they had experienced a significant past spiritual event such as an intense religious conversion.
• A study found that hyperreligious TLE patients more frequently had bilateral seizure foci than unilateral foci and more frequently reported episodes of postictal psychoses. Compared to the healthy churchgoer group, hyperreligious TLE patients more often reported actual experiences of some great spiritual figure or supernatural being – either an evil presence or a benign spiritual presence.
• A study of patients with partial-onset epilepsy found that religiosity in patients with frontal lobe seizures and in patients with TLE was significantly correlated with reduced right hippocampal volumes but not amygdalar volumes.
• Reports of religious experiences are more frequent among the schizophrenic population than the general population – especially in those patients with positive symptoms.
• As in the case of TLE, the anatomical sites of dysfunction in schizophrenia include limbic networks, the amygdala, the hippocampus, the left temporal lobe, and the dorsolateral prefrontal cortex. In addition to these TLE-related sites of pathology, schizophrenia is also associated with DA and aminergic overactivity in the limbic system and in the NAC.
• The frequency of religious obsessions in OCD populations in the United States has been estimated to lie between 10 percent and approximately 30 percent. The frequency of religious obsessions in the OCD population in countries of the Middle East runs much higher, with at least half of the patient population reporting religious obsessions.
• The clinicopathological functional and structural imaging studies of OCD suggest a consistent finding: There is abnormally increased activity in orbitofrontal cortex and in subcortical basal ganglia and limbic circuits. When patients are treated with serotonin reuptake inhibitors, the functional activity in the OFC and caudate nucleus resolves toward normal.
• An examination of the effects of symptom induction on fMRI neural activation in medication-free patients with OCD found that there was significant activation in several regions of the frontal cortex as well as the anterior, medial, and lateral temporal cortices.
• The neuropsychiatric basis of cases of scrupulosity very likely resembles that of the more typical OCD syndrome. Overactivation in the OFC and limbic system is probably key. When overactivation in the limbic system is strong enough, it may suppress drive centers in the hypothalamus, and then you would get depressive symptomology as well as hyposexuality and the like.
• In its early stages before individuals become demented, frontotemporal dementia is associated with early behavioral abnormalities, including apathy, disinhibition, and obsessive and compulsive behaviors.
• In bipolar disorder, religious delusions are much more likely in the manic than in the depressive phase of the illness and mania is associated with limbic, orbitofrontal, and right-sided temporal overactivation.
• PET and SPECT methods used for studying the brain states of experienced meditators during meditation and nuns in prayer found in both cases decreased activation levels in the parietal lobes and increased activation levels in frontal lobes. There was also increased activation seen in the cingulate gyrus bilaterally and the thalami.
• A PET scan of religious subjects showed peak blood flow activation in the right dorsolateral prefrontal cortex compared to the nonreligious subjects.
• A SPECT measurement of five Christian women who had practiced glossolalia for at least 5 years observed decreased activity in the left caudate and in the prefrontal lobes and a trend toward increased activity in the right amygdala.
• A study of Danish Christians reciting the Lord’s Prayer observed strong activation in the right caudate nucleus.
• When low dopamine is combined with high dopamine levels in the circuit, the feeling of being inundated with meaningful images and impressions is associated with positive affect, and you are much more likely to get religious experiences.
• The circuit that mediates religiousness involves primarily limbic, temporal, and frontal cortices on the right.
• An association was found between hypnotic susceptibility and the COMT polymorphism.
• A study reported a significant association between the forebrain binding potential of 5-HT1A receptors and “self-transcendence” as measured by the temperament and character inventory.
• Disorders of excessive DA and reduced serotoninergic functioning, such as schizophrenia and obsessive-compulsive disorder, are often associated with increases in religiosity. Antipsychotic agents that block DA actions at the level of the limbic system and agents that increase central serotonin activity result in reductions in religious ideation/behaviors and a resolution of religious delusions in these patients. Hallucinatory agents that purportedly enhance religious or mystical experiences do so by reducing central serotoninergic activity and enhancing central dopamine transmission.
• Impairment in DA and serotoninergic functioning in temporal and prefrontal cortical sites in humans is functionally implicated in virtually every major neuropsychiatric disorder, including depression, schizophrenia, OCD, bipolar disorder, Parkinson disease, Huntington disease, the disinhibitory impulsivity syndromes, the addictions, memory retrieval dysfunction, and the dementias.
• One of the most disabling impairments associated with traumatic brain injury (which impacts primarily the PFC) is the loss of the ability to delay gratification of prepotent or previously rewarded responses.
• In adults, prefrontal lesions are often associated with ECF deficits and disinhibition of drives and aggression.
• Sociopathy is associated with orbitofrontal dysfunction. Dorsolateral function, however, is preserved and would explain the lack of intellectual deficit in these individuals.
• A review of the literature on neuroimaging in violent offenders indicates that frontal lobe dysfunction is associated with violent offending.
• A study showed that the best predictor of violent behavior in a sample of 45 neuropsychiatric patients was a prefrontal lesion.
• Virtually all patients with evidence of prefrontal dysfunction perform poorly on tests of planning and goal-oriented behaviors.
• Regional cerebral blood flow studies have demonstrated a reduction in blood flow to frontal systems in depressed patients.
• Improvisatory prayer is associated with widespread activation in brain regions that are known to be implicated in theory of mind processing.
• A study found that religiosity (particularly intrinsic religiosity) was associated with increases in subjective happiness, health, mental health, and altruism.
• A review of studies found evidence linking religious practices and greater self-control.
• A study found that characters in REM dreams, including the dreamer, were very often aggressive, whereas characters in the NREM sleep state were found to be friendly toward the dreamer.
• An analysis of more than 500 identical and nonidentical twins found that during the transition from adolescence to adulthood, genetic factors increase in importance in determining the level of religiosity whereas shared environmental factors decrease.
• A study found that religious fundamentalism has a 0.72 heritability coefficient.
• Drugs that enhance dopamine transmission and decrease serotonin transmission can induce religious experiences in persons who are well disposed to religiousness or spirituality. Drugs that block dopamine transmission can reduce religiously tinted delusions in various psychiatric populations.
