The God Helmet is an experimental apparatus originally called the Koren helmet after its inventor Stanley Koren. It was developed by Koren and neuroscientist Michael Persinger to study creativity, religious experience and the effects of subtle stimulation of the temporal lobes. Reports by participants of a "sensed presence" while wearing the God helmet brought public attention and resulted in several TV documentaries. The device has been used in Persinger's research in the field of neurotheology, the study of the neural correlations of religion and spirituality. The apparatus, placed on the head of an experimental subject, generates very weak magnetic fields, that Persinger refers to as "complex." Like other neural stimulation with low-intensity magnetic fields, these fields are approximately as strong as those generated by a land line telephone handset or an ordinary hair dryer, but far weaker than that of an ordinary refrigerator magnet and approximately a million times weaker than transcranial magnetic stimulation.
Persinger reports that many subjects have reported "mystical experiences and altered states" while wearing the God Helmet. The foundations of his theory have been criticised in the scientific press. Anecdotal reports by journalists, academics and documentarists have been mixed and several effects reported by Persinger have not yet been independently replicated. One attempt at replication published in the scientific literature reported a failure to reproduce Persinger's effects and the authors proposed that the suggestibility of participants, improper blinding of participants or idiosyncratic methodology could explain Persinger's results. Persinger argues that the replication was technically flawed, but the researchers have stood by their replication. More recently, other researchers  have published a replication of one God Helmet experiment.
The God Helmet was not specifically designed to elicit visions of God, but to test several of Persinger's hypotheses about brain function. The first of these is the Vectorial Hemisphericity Hypothesis, which proposes that the human sense of self has two components, one on each side of the brain, that ordinarily work together but in which the left hemisphere is usually dominant. Persinger argues that the two hemispheres make different contributions to a single sense of self, but under certain conditions can appear as two separate 'selves'. Persinger and Koren designed the God Helmet in an attempt to create conditions in which contributions to the sense of self from both cerebral hemispheres is disrupted.
The second experimental hypothesis was that when communication between the left and right senses of self is disturbed, as they report it is while wearing the God Helmet, the usually-subordinate 'self' in the right hemisphere intrudes into the awareness of the left-hemispheric dominant self, causing what Persinger refers to as "interhemispheric intrusions".
The third hypothesis was that "visitor experiences" could be explained by such "interhemispheric intrusions" caused by a disruption in "vectorial hemisphericity". Persinger theorises that many paranormal experiences, feelings of having lived past lives, felt presences of non-physical beings, ghosts, muses, and other "spiritual beings", are examples of interhemispheric intrusions (an idea originally proposed in 1976 in Julian Jaynes' bicameralism hypothesis).
The God Helmet experiments were also intended, though not specifically designed (see above), to validate the idea that religious and mystic experiences are artifacts of temporal lobe function.
Persinger uses a modified snowmobile helmet that incorporates solenoids placed over the temporal lobes. This device produces magnetic fields that Persinger describes as "weak but complex" (1 microTesla). The pattern of fluctuation in these magnetic fields is derived from physiological sources, for example patterns that appear in EEG traces taken from limbic structures. The purpose of exposing magnetic fields patterned after neurophysiological sources, such as the burst-firing profile of the amygdala, is to enhance the probability of activating the structure from which the signal was derived. Only one of the coils on each side of the helmet is active at any one time, and the active coil changes constantly, "rotating" counterclockwise over each temporal lobe.[relevant? ] Persinger's God Helmet sessions consist of two stimulations, applied one after the other. The first of these uses a signal "tailored from a Chirp Signal sequence, applied over right temporal lobe.[relevant? ] In the second phase of the procedure, both temporal lobes are stimulated, with a pattern derived from the amygdala.
The sessions are conducted with the subject seated in an acoustic chamber. The acoustic chamber is also a Faraday cage, shielding out all EMF emissions and radiation except the Earth's magnetic field. Persinger reports that this shielding allows him to use the apparatus to investigate the effects of geomagnetism on the human brain.
Comparison with TMS
Neither the God Helmet, nor technologies derived from it, are examples of transcranial magnetic stimulation (TMS), which uses magnetic fields on the order of one million times stronger than those used in Persinger's lab. Despite this, Persinger reports similar effect sizes with his apparatus. The magnetic fields employed in TMS and in Persinger's experiments are also very different. TMS uses single, paired, and repetitive pulses of high intensity to penetrate the cranium. In contrast, Persinger's apparatus uses weak complex magnetic signals patterned after physiological processes, such as one derived from limbic burst firing.
Most reports from Persinger's lab consist of people sensing "presences"; people often interpreted these to be that of angels, a deceased being known to the subject, or a group of beings of some kind. There have also been reports in which the participant has experienced what they perceive as God. Persinger reports that "at least" 80 percent of his participants experience a presence beside them in the room, whilst about one percent report an experience of "God",[self-published source?] and others report less evocative experiences of "another consciousness or sentient being".
The scientist and science writer Richard Dawkins, appearing in the BBC science documentary series Horizon, did not have a 'sensed presence' experience, but instead felt at times 'slightly dizzy', 'quite strange' and had sensations in his limbs and changes in his breathing. He summarised his experience as follows: "It pretty much felt as though I was in total darkness, with a helmet on my head and pleasantly relaxed". Persinger explained Dawkins' limited results in terms of his low score on a psychological scale measuring temporal lobe sensitivity.
In contrast, the experimental psychologist, and former parapsychology researcher, Susan Blackmore said: "When I went to Persinger's lab and underwent his procedures I had the most extraordinary experiences I've ever had… I'll be surprised if it turns out to be a placebo effect."
Jack Hitt, a journalist from Wired magazine, visited Persinger's lab in 1999 and expressed confusion over Persinger's post-stimulation debriefing ("One question: Did the red bulb on the wall grow larger or smaller? There was a red bulb on the wall? I hadn't noticed.") and reported: "Many other questions suggest that there were other experiences I should have had, but to be honest, I didn't. In fact, as transcendental experiences go, on a scale of 1 to 10, Persinger's helmet falls somewhere around, oh, 4. Even though I did have a fairly convincing out-of-body experience, I'm disappointed relative to the great expectations and anxieties I had going in."
Replication and debate
In 2014, Tinoco and Ortiz succeeded in replicating the effects of one of Persinger's early studies. They reported that their experiment had ruled out suggestibility as an explanation for Persinger's effects, and that analysis of their subjects’ verbal reports revealed significant differences between the speech of subjects and controls, as well as less robust effects for suggestion and expectation.
In December 2004 Nature reported that a group of Swedish researchers led by Pehr Granqvist, a psychologist at Uppsala University in Sweden, had attempted to replicate Persinger's experiments under double-blind conditions, and were not able to reproduce the effect. The study was published in Neuroscience Letters in 2005. Granqvist et al concluded that the presence or absence of the magnetic field had no relationship with any religious or spiritual experience reported by the participants, but was predicted entirely by their suggestibility and personality traits. Persinger, however, took issue with the Swedish attempt to replicate his work. "They didn't replicate it, not even close," he says. He argued that the Swedish group did not expose the subjects to magnetic fields for long enough to produce an effect. Granqvist et al. respond that Persinger agreed with their proposed methodology beforehand and they stand by their replication.
Related devices and studies
Persinger and colleagues also developed a device nicknamed "The Octopus" which uses solenoids around the whole brain, in a circle just above subject's ears. Commercial versions of the God helmet, Octopus and associated devices are sold by Persinger’s research associate Todd Murphy, and he reports that his devices are able to modulate emotional states in addition to enhancing meditation and generating altered states. One experiment found no changes in emotional responses to photographs whether the device was on or off, although the researchers concluded that "additional investigations ... are warranted." Persinger and colleagues report significant changes in subjects' EEG during stimulation with a Shakti system. In one report by Persinger's lab, these changes were correlated with an out-of-body experience.
One published attempt to test Persinger's theories regarding the psychological effects of environmental magnetic fields, used whole-body exposure to magnetic fields and ultrasound in freely-moving participants to create a "haunted room" within which it was hoped subjects would sense a "presence". The study found that reports of unusual experiences were unrelated with the presence or absence of "complex" environmental electromagnetic fields similar to Persinger's. They concluded that the effects were likely due to suggestibility, though they did not directly measure it.
- Ruttan, L. A., Persinger, M. A. & Koren, S. (1990). "Enhancement of Temporal Lobe-Related Experiences During Brief Exposures to MilliGauss Intensity Extremely Low Frequency Magnetic Fields". Journal of Bioelectricity. 9 (1): 33–54. doi:10.3109/15368379009027758.
- Science Channel clip of God Helmet
- Craig Aaen-Stockdale (2012). "Neuroscience for the Soul". The Psychologist. 25 (7): 520–523.
the magnetic fields generated by the God helmet are far too weak to penetrate the cranium and influence neurons within. Transcranial magnetic stimulation (TMS) uses field strengths of around 1.5 tesla in order to induce currents strong enough to depolarise neurons through the skull and cause them to fire. Persinger’s apparatus, on the other hand has a strength ... 5000 times weaker than a typical fridge magnet. Granqvist argues that there is simply no way that this apparatus is having any meaningful effect on the brain, and I’m inclined to agree.
- Persinger, MA; et al. (2010). "The Electromagnetic Induction of Mystical and Altered States Within the Laboratory". Journal of Consciousness Exploration & Research. 1 (7): 808–830. ISSN 2153-8212.
- Craig Aaen-Stockdale (2012). "Neuroscience for the Soul". The Psychologist. 25 (7): 520–523.
Persinger’s theory is based on the literature on religiosity in temporal lobe epileptics ... a literature that I argue above is both flawed and outdated.
- Wired magazine article
- Online video excerpt, see 2:00 to 3:26
- Roxanne Khamsi (December 9, 2004). "Electrical brainstorms busted as source of ghosts". BioEd Online.
- Incomplete filmography for Dr. M.A. Persinger
- Granqvist, P; Fredrikson, M; Unge, P; Hagenfeldt, A; Valind, S; Larhammar, D; Larsson, M (2005). "Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak complex magnetic fields". Neuroscience Letters. 379 (1): 1–6. doi:10.1016/j.neulet.2004.10.057. PMID 15849873. Lay summary – BioEd Online (December 9, 2004).
- Persinger, M; Koren, S (2005). "A response to Granqvist et al. "Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak magnetic fields"". Neuroscience Letters. 380 (3): 346–347. doi:10.1016/j.neulet.2005.03.060. PMID 15862915.
- Larsson, M., Larhammarb, D., Fredrikson, M., and Granqvist, P. (2005). "Reply to M.A. Persinger and S. A. Koren's response to Granqvist et al. "Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak magnetic fields"". Neuroscience Letters. 380 (3): 348–350. doi:10.1016/j.neulet.2005.03.059.
- Tinoca,, Carlos A;; Ortiz,, João PL; (2014). "Magnetic Stimulation of the Temporal Cortex: A Partial "God Helmet" Replication Study". Journal of Consciousness Exploration & Research. 5 (3): 234–257. Lay summary.
- Richards, P M; Persinger, M A; Koren, S A (1993). "Modification of activation and evaluation properties of narratives by weak complex magnetic field patterns that simulate limbic burst firing.". The International Journal of Neuroscience. 71 (1-4): 71–85. Lay summary – " subjects exposed to a computer-generated wave form, designed to simulate neuronal burst firing, generated narratives dominated by more pleasantness and less activation than a reference group.".
- Persinger, M A (1993). "Vectorial cerebral hemisphericity as differential sources for the sensed presence, mystical experiences and religious conversions". Perceptual and motor skills. 76 (3 Pt 1): 915–30. doi:10.2466/pms.19126.96.36.1995. PMID 8321608.
- Persinger, Michael A; Healey, Faye (2002). "Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields". The Journal of Nervous and Mental Disease. 190 (8): 533–41. doi:10.1097/00005053-200208000-00006. PMID 12193838.
- Persinger, Michael A; Bureau, YR; Peredery, OP; Richards, PM (1994). "The sensed presence within experimental settings: implications for the male and female concept of self". The Journal of psychology. 78 (3 Pt 1): 999–1009. PMID 8084725. Lay summary – Popular article about the "sensed presence".
- Persinger, M A (1989). "Geophysical variables and behavior: LV. Predicting the details of visitor experiences and the personality of experients: the temporal lobe factor". Perceptual and motor skills. 68 (1): 55–65. doi:10.2466/pms.19188.8.131.52. PMID 2648314.
- Persinger, M A (1993). "Paranormal and religious beliefs may be mediated differentially by subcortical and cortical phenomenological processes of the temporal (limbic) lobes". Perceptual and motor skills. 76 (1): 247–51. doi:10.2466/pms.19184.108.40.206. PMID 8451133.
- Persinger MA, MA (1996). "Feelings of past lives as expected perturbations within the neurocognitive processes that generate the sense of self: contributions from limbic lability and vectorial hemisphericity". Perceptual and Motor Skills. 83 (3, pt 2): 1107–21. doi:10.2466/pms.1996.83.3f.1107. PMID 9017718.
- Persinger, M A (1992). "Enhanced incidence of "the sensed presence" in people who have learned to meditate: support for the right hemispheric intrusion hypothesis". Perceptual and motor skills. 75 (3 Pt 2): 1308–10. doi:10.2466/PMS.75.8.1308-1310. PMID 1484802.
- Persinger, M A; Tiller, S G; Koren, S A (2000). "Experimental simulation of a haunt experience and elicitation of paroxysmal electroencephalographic activity by transcerebral complex magnetic fields: induction of a synthetic "ghost"?". Perceptual and motor skills. 90 (2): 659–74. doi:10.2466/PMS.90.2.659-674. PMID 10833767.
- Persinger MA, MA; Makarec K., K (1992). "The feeling of a presence and verbal meaningfulness in context of temporal lobe function: factor analytic verification of the muses?". Brain and Cognition. 20 (2): 217–26. doi:10.1016/0278-2626(92)90016-F. PMID 1449754.
- Persinger, M A (1991). "Religious and mystical experiences as artifacts of temporal lobe function: a general hypothesis". Perceptual and motor skills. 57 (3 Pt 2): 1255–62. doi:10.2466/pms.1983.57.3f.1255. PMID 6664802.
- Booth, J. N.; Koren, S. A.; Persinger, M. A. (2008). "Increased Theta Activity in Quantitative Electroencephalographic (QEEG) Measurements During Exposure to Complex Weak Magnetic Fields". Electromagnetic Biology and Medicine. 27 (4): 426–36. doi:10.1080/15368370802493719. PMID 19037792.
- Tsang, E. W.; Koren, S. A.; Persinger, M. A. (2004). "Power increases within the gamma range over the frontal and occipital regions during acute exposures to cerebrally counterclockwise rotating magnetic fields with specific derivatives of change". International Journal of Neuroscience. 114 (9): 1183–93. doi:10.1080/00207450490475643. PMID 15370182.
- Healey, F; Persinger, MA; Koren, SA. (1996). "Enhanced hypnotic suggestibility following application of burst-firing magnetic fields over the right temporoparietal lobes: a replication". International Journal of Neuroscience. 3–4 (3): 201–7. doi:10.3109/00207459609070838. PMID 9003980.
- Persinger, M A (2001). "The neuropsychiatry of paranormal experiences". The Journal of Neuropsychiatry and Clinical Neurosciences. 13 (4): 515–24. doi:10.1176/appi.neuropsych.13.4.515. PMID 11748322.
- Richards PM, Persinger MA, Koren SA (1993). "Modification of Activation and Evaluation Properties of Narratives by Weak Complex Magnetic Field Patterns that Simulate Limbic Burst Firing". International Journal of Neuroscience. 71 (1-4): 71–85. doi:10.3109/00207459309000594.
- Persinger, M A (1999). "Increased emergence of alpha activity over the left but not the right temporal lobe within a dark acoustic chamber: differential response of the left but not the right hemisphere to transcerebral magnetic fields". International Journal of Psychophysiology. 34 (2): 163–9. doi:10.1016/S0167-8760(99)00069-0. PMID 10576400.
- Booth, J N; Koren, S A; Persinger, M A (2005). "Increased feelings of the sensed presence and increased geomagnetic activity at the time of the experience during exposures to transcerebral weak complex magnetic fields". The International Journal of Neuroscience. 115 (7): 1053–79. doi:10.1080/00207450590901521. PMID 16051550.
- Churchill, D R; Persinger, M A; Thomas, A W (1994). "Geophysical variables and behavior: LXXVII. Increased geomagnetic activity and decreased pleasantness of spontaneous narratives for percipients but not agents". Perceptual and motor skills. 79 (1 Pt 2): 387–92. doi:10.2466/pms.19220.127.116.117. PMID 7808872.
- Auvichayapat, P; Auvichayapat, N (2009). "Basic principle of transcranial magnetic stimulation". Journal of the Medical Association of Thailand. 92 (11): 1560–6. PMID 19938752.
- Meli, Salvatore C.; Persinger, Michael A. (2009). "Red Light Facilitates the Sensed Presence Elicited by Application of Weak, Burst-Firing Magnetic Fields Over the Temporal Lobes". International Journal of Neuroscience. 119 (1): 68–75. doi:10.1080/00207450802507689. PMID 19116832.
- Persinger, MA (2001). "The neuropsychiatry of paranormal experiences". The Journal of Neuropsychiatry & Clinical Neurosciences. 13 (4): 515–524. doi:10.1176/appi.neuropsych.13.4.515. PMID 11748322.
- St-Pierre, LS, Persinger, MA (2006). "Experimental Facilitation of the Sensed Presence Is Predicted By The Specific Patterns of the Applied Magnetic Fields, Not By Suggestibility: Re-analysis of 19 Experiments". International Journal of Neuroscience. 116 (9): 1079–1095. doi:10.1080/00207450600808800. PMID 16861170.
- "Email quoted here".
- Booth, J. N.; Persinger, M. A. (2009). "Discrete Shifts Within the Theta Band Between the Frontal and Parietal Regions of the Right Hemisphere and the Experiences of a Sensed Presence". Journal of Neuropsychiatry. 21 (3): 279–83. doi:10.1176/appi.neuropsych.21.3.279.
- Video footage, see 3:04-7 and 3:32-43
- BBC Article
- Jack Hitt (Nov 1999). "This Is Your Brain on God". Wired. 7 (11).
- "Email between Persinger and Granqvist November 2004".
- Persinger, MA (1983). "Religious and mystical experiences as artifacts of temporal lobe function: a general hypothesis". Perceptual and motor skills. 57 (3 Pt 2): 1255–62. doi:10.2466/pms.1983.57.3f.1255. PMID 6664802.
- Persinger, MA (1993). "Paranormal and religious beliefs may be mediated differentially by subcortical and cortical phenomenological processes of the temporal (limbic) lobes". Perceptual and motor skills. 76 (1): 247–51. doi:10.2466/pms.1918.104.22.168. PMID 8451133.
- Craig Aaen-Stockdale (2012). "Neuroscience for the Soul". The Psychologist. 25 (7): 520–523.
Murphy claims his devices are able to modulate emotional states in addition to enhancing meditation and generating altered states. Gendle & McGrath (2012) found no significant difference in emotional responses to photographs whether the device was on or off.
- Gendle, MH; McGrath, MG (2012). "Can the 8-coil shakti alter subjective emotional experience? A randomized, placebo-controlled study.". Perceptual and Motor Skills. 114 (1): 217–235. doi:10.2466/02.24.pms.114.1.217-235.
- Tsang EW, Koren SA, Persinger MA (2004). "Electrophysiological and Quantitative Electroencephalographic Measurements After Treatment By Transcerebral Magnetic Fields Generated By Compact Disc Through A Computer Sound Card: The Shakti Treatment". International Journal of Neuroscience. 114: 1013, 1024. doi:10.1080/00207450490461323.
- Saroka KS, Mulligan BP, Persinger MA, Murphy, TR. (2010). "Experimental elicitation of an Out-of-Body Experience and concomitant cross-hemispheric electroencephalographic coherence". NeuroQuantology. 8: 466–477. doi:10.14704/nq.2010.8.4.302.
- French, CC., Haque, U., Bunton-Stasyshyn, R., Davis, R. (2009). "The "Haunt" project: An attempt to build a "haunted" room by manipulating complex electromagnetic fields and infrasound". Cortex. 45 (5): 619–629. doi:10.1016/j.cortex.2007.10.011. PMID 18635163.