Question: Are “microseizures” (a concept you have used to help explain religious experiences) actually epileptic events? (A Blog by Dr. M.A. Persinger)
Answer: No, although they do have some things in common with epileptic events (seizures) because they originate from the same source; i.e., moments of instability in the temporal lobes, most particularly in it’s deeper (limbic) regions. Most phenomena that share a common cause are distributed along a continuum (or spectrum) of intensity with degrees of “how much” (or how strong). For example, a few times during their lives, for brief periods, most people display the symptoms that define depression, thought disorders (such as schizophrenia) and personality disorders. However, it is only when the symptoms dominate the person’s behaviours more or less continuously, that the condition is considered abnormal. To employ a metaphor, ordinary religious experiences rely on brief “unsettled” conditions in the temporal lobes, but not full temporal lobe epileptic seizures.
“Microseizures” is a term I borrowed from Goldensohn (1975, 1983) who described epileptic activity from the small columns within the cerebral cortices induced by surgical electrodes (that was not evident by typical scalp brain wave activity) to indicate subclinical electrical patterns that shared some features with (but were not the same as) epileptic events. A more recent publication (Stead, et al., 2010) describes Goldensohn’s findings as follows:
“They demonstrated focal evolving microepileptiform discharges after penicillin injection on single electrodes in an array of electrodes spaced 2 mm apart with no reflection of the discharges on adjacent electrodes.”
In other words, electrical discharges creating EEG (electroencephalographic) patterns which are similar to epileptic activity can appear from the brain. These don’t spread to other areas the way true epileptic seizure activity does. Note that in the above quotation, such activity was read from one sensor, but the other, only two millimeters away, did not detect it. This has been the primary exemplar of microseizures in my work. To clarify further, microseizures are non-epileptic events that mimic seizural activity, taking place in exceedingly small (“pinpoint”) volumes of brain space.
My theory of the continuum of temporal lobe lability (offered as an explanation for the wide differences between religious and non-religious personality types and the propensity to report religious experiences) is not based upon the rich literature demonstrating links between religiosity and temporal lobe epileptics (and, more broadly, temporal lobe foci). This link has been repeatedly observed and is still observed in some populations. Instead, my theory is based on laboratory measurements of normal, non-epileptic people. I think it is important to emphasize that the research began and continues to be focused upon creativity and the factors that allow human beings to adapt to complex and ever changing environments and circumstances. Sensitivity, but without actual epilepsy, at the upper end of the continuum of temporal lobe lability is associated with remarkable creativity.
Many epileptics have had religious experiences, but only a very small minority of people reporting such experiences are epileptics. Moreover, only a very small percent of all epileptics report such experiences. We can easily understand how the relative importance of religion in human cultures has given them a disproportionate prominence in the literature surrounding the study of the neurological aspects of religion and spirituality, i.e., the field of neurotheology.
The sensed presence is a primary feature of above-average temporal lobe sensitivity. It has been given different labels that range from the Muses of the Ancient Greeks to the “spirit guides” of contemporary New Age religion and philosophy. My working explanation is that the sensed presence is the left hemispheric awareness of the right hemispheric equivalent of the sense of self. We have demonstrated the direction effect across the two hemispheres and lobes by neuroimaging.
Goldensohn ES. Initiation and propagation of epileptogenic foci. In: JK Penry and DD Daly, editors. Advances in neurology. New York: Raven Press; 1975.
Matt Stead (et al.) “Microseizures and the spatiotemporal scales of human partial epilepsy” Brain. 2010 Sep; 133(9): 2789–2797.
Goldensohn ES., “Symptomatology of nonconvulsive seizures: ictal and postictal.” Epilepsia. 1983;24 Suppl 1:S5-21.
Dr. Michael A. Persinger
Behavioural Neuroscience, Biomolecular Sciences and Human Studies
Departments of Psychology and Biology
Sudbury, Ontario, Canada P3E 2C6
Email: email@example.com and firstname.lastname@example.org
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