Sensed presence, neurotheology and a contested experiment
Michael Persinger, Todd Murphy and the “God Helmet”
Could weak, patterned magnetic fields make somebody feel that another presence had entered the room? An unusual laboratory apparatus became a cultural symbol for the attempt to locate spiritual experience in the brain.
Andrew T. Austin with the Shakti god helmet (with mis-placed coils).
The first correction
One famous name, three different contributions
The original apparatus was known as the Koren helmet. Stanley A. Koren developed the equipment with Michael A. Persinger at Laurentian University. Persinger supplied the wider theoretical programme and led many of the experiments. “God Helmet” was a later media nickname, not the instrument’s original scientific name.
Todd Murphy did not co-invent the Koren helmet, but he later adapted and popularised related methods through commercial Shakti systems. His lectures on YouTube are well worth viewing. According to Murphy’s own curriculum vitae, he developed two-coil, four-coil and eight-coil versions between 2003 and 2005, describing the eight-coil Shakti as an approximation of the Koren helmet.
A precise history separates Persinger’s hypotheses, Koren’s engineering and Murphy’s later adaptation. Treating all three as one invention makes the story simpler, but less accurate.
The apparatus
How the Koren helmet experiment was arranged
1. Position
Solenoids mounted on a modified helmet were placed around temporal and temporoparietal regions of the head.
2. Pattern
The coils produced weak, time-varying magnetic fields. Persinger argued that the temporal pattern mattered more than raw strength.
3. Context
Participants usually sat alone in a quiet, darkened acoustic chamber, reducing ordinary sensory cues and social contact.
4. Report
Researchers collected ratings and verbal accounts of bodily sensations, emotion, imagery and any sensed presence.
A 2002 controlled experiment described fields of about 100 nanotesla to 1 microtesla and compared right-sided, left-sided, bilateral and sham conditions. These are extremely weak fields. The apparatus did not deliver the intense, rapidly changing pulses used in clinical transcranial magnetic stimulation.
The “God Helmet” is not clinical TMS
Field strength
Koren helmet and Shakti
Typically reported in the nanotesla to low-microtesla range.
Clinical or research TMS
Brief magnetic pulses commonly reach the tesla range at the coil.
Waveform
Koren helmet and Shakti
Weak, complex temporal patterns delivered for many minutes.
Clinical or research TMS
High-intensity single or repeated pulses designed to induce a cortical electric field.
Target engagement
Koren helmet and Shakti
The proposed neural effect remains disputed and is not established by motor threshold or equivalent physiological calibration.
Clinical or research TMS
Sufficient stimulation over motor cortex can evoke a measurable muscle response. Clinical protocols use regulated equipment and defined dosing procedures.
Purpose
Koren helmet and Shakti
Experimental study of subjective experience, with later commercial claims around meditation and altered states.
Clinical or research TMS
Neuroscience research and regulated clinical treatment for selected conditions.
Evidence
Koren helmet and Shakti
Small, contested literature with important null replications.
Clinical or research TMS
Large field with condition-specific trials, professional guidance and regulatory oversight.
Calling both methods “magnetic brain stimulation” can conceal enormous differences in field strength, waveform, calibration, intended mechanism and clinical status.
Buy this book.
The central experience
What is a sensed presence?
A sensed presence is the vivid impression that another person or being is nearby when no clear sensory evidence identifies one. It need not involve a visual apparition. The presence may feel located behind the shoulder, beside the body or elsewhere in a room. It may be comforting, neutral, watchful or threatening.
Such experiences have been reported during bereavement, sleep paralysis, extreme isolation, mountaineering, neurological illness, intense stress and spiritual practice. The experience is psychologically real to the person. That does not by itself establish whether its cause is magnetic stimulation, expectation, unusual sensory conditions, a neurological event or a combination of factors.
Experience and explanation are different questions. A person can accurately report having felt a presence while remaining mistaken, uncertain or undecided about what produced it.
Persinger’s explanatory model
From temporal-lobe instability to an “other self”
Persinger proposed that unusual electrical activity or “lability” in temporal and limbic systems could help generate mystical, religious and paranormal experiences. His 1983 temporal-lobe hypothesis treated these experiences as points on a continuum rather than evidence that every experiencer had epilepsy.
A later account, sometimes called the vectorial hemisphericity hypothesis, suggested that the normal sense of self depends on coordinated activity between the cerebral hemispheres. Under unusual conditions, a normally integrated right-hemisphere contribution to selfhood was said to intrude into left-hemisphere awareness and be experienced as another presence. Personal history and culture would then help determine whether that presence was interpreted as a deceased relative, spirit, angel, deity or unnamed being.
This model was imaginative and testable in principle, but its strong left-self/right-other division is much simpler than contemporary network accounts of self-processing. Modern work distributes bodily selfhood, agency and social presence across temporoparietal, insular, sensorimotor, frontal and subcortical systems.
Showing that a spiritual experience has neural correlates does not decide whether its religious interpretation is true or false. A brain process is involved in every human experience.
Historical timeline
From temporal-lobe theory to the Shakti era
1971
Persinger joins Laurentian University in Sudbury, Ontario.
Why it matters: The university becomes the base for his long research programme on electromagnetic fields, unusual experience and brain function.
1983
Persinger publishes “Religious and Mystical Experiences as Artifacts of Temporal Lobe Function”.
Why it matters: The paper presents a general temporal-lobe hypothesis for religious and mystical experience.
1987
Neuropsychological Bases of God Beliefs is published.
Why it matters: Persinger develops his attempt to connect brain processes, personal history and beliefs about God.
Late 1980s to 1990s
Stanley Koren and Michael Persinger develop helmet and coil arrangements for applying weak complex magnetic fields.
Why it matters: The Koren helmet becomes the most recognisable apparatus within a wider programme using solenoids and “Koren boxes”. The surviving literature does not support a single, securely documented invention day.
1997
Persinger’s group publishes experimental reports on weak complex fields, EEG activity and the sensed presence.
Why it matters: Claims begin to move from a broad theory towards named laboratory procedures and measurable outcomes.
1999
Wired publishes “This Is Your Brain on God”.
Why it matters: The “God Helmet” label and first-person accounts bring the work to an international popular audience.
2000
Persinger, Tiller and Koren report an attempted experimental simulation of a haunt experience.
Why it matters: The paper links weak complex fields, EEG observations and the provocative idea of a synthetic “ghost”. It is a case report, not decisive evidence of a general effect.
2002
A 48-participant study reports experimental facilitation of the sensed presence.
Why it matters: The paper becomes one of the clearest controlled statements of Persinger’s causal claim.
2003
BBC Horizon broadcasts God on the Brain. Murphy reports developing a two-coil Shakti system.
Why it matters: Media exposure intensifies. Murphy’s later technology begins a separate adaptation and commercialisation phase.
2004
Murphy reports a four-coil Shakti. Tsang, Koren and Persinger publish an electrophysiological study using Shakti equipment.
Why it matters: The paper records laboratory use of equipment credited to Murphy, but Murphy is not an author and the study does not establish a spiritual or clinical benefit.
2005
Murphy reports an eight-coil Shakti approximation. Granqvist and colleagues publish a double-blind null replication.
Why it matters: The replication finds that suggestibility and personality measures, not active fields, predict reports. Persinger and Koren dispute whether it faithfully reproduced their method.
2006
Persinger’s group publishes a reanalysis of 19 experiments.
Why it matters: The authors argue that specific field patterns predict sensed presence better than suggestibility. Because the analysis comes from the originating laboratory, it does not replace independent replication.
2006 to 2009
Other researchers induce presence-like experiences through direct electrical stimulation, while the independent Haunt project finds unusual reports unrelated to active weak fields or infrasound.
Why it matters: The broader neuroscience of presence develops, but does not confirm the Koren helmet mechanism.
2012
A randomised placebo-controlled study of the eight-coil Shakti is published.
Why it matters: Thirty-seven participants show no significant active-versus-sham difference in subjective emotional responses.
2014
Neurologists report robot-controlled induction of an apparition.
Why it matters: Experimentally produced sensorimotor conflict offers a different mechanism for felt presence involving disrupted bodily self-processing.
2018
Michael Persinger dies at the age of 73.
Why it matters: His work leaves a mixed legacy: prolific, theoretically bold, culturally influential and persistently controversial.
2019
A sham-helmet study is published online in 2017 and in print in 2019: exceptional experiences occur without active stimulation.
Why it matters: Belief, synaesthesia and sensory sensitivity help predict reports, adding weight to expectancy and individual-difference explanations.
Timeline note: Murphy’s 2003 to 2005 development dates come from his own published curriculum vitae and should be read as self-reported history. The original apparatus belongs to the Koren and Persinger research programme.
Persinger, Koren and Murphy
Michael A. Persinger
An American-born psychologist and neuroscientist who spent most of his career at Laurentian University. His work crossed behavioural neuroscience, geomagnetism, temporal-lobe phenomena, paranormal experience and consciousness. He framed the sensed presence as a possible laboratory bridge between brain function and experiences often described in religious language.
Stanley A. Koren
A long-term Laurentian collaborator whose engineering and technical contribution is preserved in the name “Koren helmet” and in references to Koren boxes. Popular accounts often reduce the device to Persinger alone, obscuring Koren’s role in developing the hardware used by the research programme.
Todd R. Murphy
An independent researcher, writer and technology developer who translated elements of the Laurentian work into Shakti systems driven through consumer computer equipment. Murphy became an important interpreter and promoter of Persinger’s ideas, but this role must be distinguished from co-invention of the original apparatus and from independent scientific confirmation.
Todd Murphy’s adaptation
From laboratory apparatus to Shakti systems
Murphy’s Shakti project used compact coils and patterned signals delivered through computer audio hardware. Different arrangements used two, four or eight coils. The later eight-coil version was presented as an approximation of the spatially distributed Koren apparatus rather than an exact replica.
This made the underlying idea portable and available outside Persinger’s laboratory. It also changed the evidential setting. A commercial or self-directed experience cannot reproduce the blinding, calibration, field measurement, interview procedures and experimental control required for a scientific test.
A 2004 paper by Tsang, Koren and Persinger examined electrophysiological measurements after exposure using a Shakti configuration and Koren boxes. The authors acknowledged Murphy for equipment and cooperation. This paper is evidence that Shakti hardware entered laboratory work, not evidence that the device reliably causes mystical experience or treats a health condition.
Commercial availability is not independent validation. Testimonials and vivid first-person reports can generate research questions, but they cannot establish efficacy without suitable controls.
An excellent rewriting of the research papers for the lay-reader. Buy this book!
What the studies found
A mixed and methodologically difficult evidence base
Persinger et al., 2002
Design and result: Forty-eight participants received right, left, bilateral or sham field conditions. The authors reported experimental facilitation of a sensed presence.
Interpretation: A controlled positive result from the originating laboratory. It supports further testing, but does not establish independent reproducibility.
Tsang et al., 2004
Design and result: Examined electrophysiological and quantitative EEG measures following weak-field exposures using Shakti and Koren configurations.
Interpretation: Reports physiological measurements under particular conditions. It does not demonstrate a reliable mystical experience, health benefit or everyday effectiveness.
Granqvist et al., 2005
Design and result: Eighty-nine participants took part in a double-blind test. Active fields did not significantly increase sensed presence or mystical experience. Suggestibility and personality-related measures predicted outcomes.
Interpretation: A major independent null result. Persinger and Koren argued that technical differences made it an inadequate replication; Granqvist’s group stood by the method.
St-Pierre and Persinger, 2006
Design and result: A reanalysis of 19 experiments concluded that field pattern, rather than suggestibility, predicted sensed presence.
Interpretation: Aggregates a substantial programme, but remains an analysis from the originating group and is vulnerable to differences among studies and analytic choices.
French et al., 2009
Design and result: Seventy-nine participants spent 50 minutes in a purpose-built room with infrasound, complex electromagnetic fields, both or neither. Reports were unrelated to the active manipulations.
Interpretation: Challenges a general claim that weak complex fields reliably cause haunt-type sensations. The whole-room exposure was not identical to the Koren helmet.
Gendle and McGrath, 2012
Design and result: Thirty-seven participants received active or sham exposure from an eight-coil Shakti while rating emotional images. No significant active-versus-sham difference was found.
Interpretation: An independent randomised test of a commercial descendant. It tested emotional response, not every claim made for the apparatus.
Simmonds-Moore et al., 2019
Design and result: Participants reported exceptional experiences during sham helmet sessions. Belief, synaesthesia and sensory sensitivity helped predict aspects of the reports.
Interpretation: Shows how unusual experiences can arise without active stimulation in an evocative setting. It does not prove that all earlier reports were insincere or identical in cause.
The strongest defensible conclusion is not that the helmet “works” or that nothing happened. It is that unusual experiences were reported, while the specific causal role of weak patterned fields has not been established through robust independent replication.
Why replication became the central issue
A technically specific claim
Persinger argued that effects depended on exact temporal patterns, coil geometry, sequence, duration and field intensity. That makes faithful replication demanding, but it also creates many opportunities to explain away a null result after the event.
An expectancy-rich setting
A helmet, darkness, isolation and questions about presences can create strong expectations. Blinding must cover participants, experimenters, interviewers and analysts wherever possible. Sham conditions must feel equally credible.
A flexible outcome
“Sensed presence” can range from a faint impression to a named being. Open interviews capture richness but invite coding judgement. Predefined outcomes, preregistered analyses and transparent data reduce interpretive flexibility.
A decisive modern test would pre-register the waveform, hardware, field mapping, session timing, interview script, primary outcome and analysis. It would use credible sham stimulation, verify blinding, include adequate statistical power and be repeated by laboratories independent of the apparatus’s advocates.
Beyond the helmet
What later neuroscience says about the “felt presence”
In 2006, Olaf Blanke and colleagues reported that direct electrical stimulation near the left temporoparietal junction of a patient with epilepsy produced the impression of a shadowy person. In 2014, a robot created mismatches between a participant’s movement and delayed tactile feedback, inducing presence-like experiences in healthy volunteers. Neurological lesion analysis and imaging implicated a distributed network involved in sensorimotor integration and bodily self-representation.
These findings make the general idea that a presence can be generated by brain processes plausible. They do not validate Persinger’s specific proposal that weak patterned magnetic fields reliably produce it. The manipulation, field strength, anatomical inference and measured mechanism are different.
Supported more broadly
Felt presence is a genuine class of human experience. Changes in sensorimotor integration, bodily self-representation and neurological function can contribute to it.
Not established
The available evidence does not show that the Koren helmet or Shakti systems reliably generate spiritual experience, prove a “God spot” or provide a validated treatment.
Translating the headlines
What popular claims leave out
“The helmet makes people feel God.”
Some participants reported a sensed presence or other unusual experience. Reports were not universal, not always religious and have not been reliably reproduced under independent blinded conditions.
“It stimulates the temporal lobes.”
Coils apply weak patterned fields near temporal and temporoparietal areas. Direct, selective neural target engagement has not been demonstrated in the manner used to validate TMS.
“Eighty per cent of people feel a presence.”
This widely repeated figure is associated with Persinger’s descriptions of his programme, not a stable effect confirmed across independent preregistered trials.
“The experiment proves God is generated by the brain.”
No laboratory experiment can settle a metaphysical question simply by identifying a neural process. The causal role of the helmet is itself disputed.
“The failed replication proves the whole idea was false.”
The null studies seriously weaken the specific weak-field claim. They do not erase the broader neurological study of mystical experience or felt presence.
“Shakti is the portable God Helmet.”
Murphy described the eight-coil version as an approximation. Hardware, spatial arrangement, calibration, context and research procedure are not necessarily equivalent.
“It is a low-power form of TMS.”
The field strengths and intended mechanisms differ by many orders of magnitude. Treating the systems as interchangeable is misleading.
Why the metaphor became larger than the apparatus
“God Helmet” is an exceptionally efficient metaphor. It joins a sacred concept to an ordinary object and promises an immediate bridge between invisible belief and visible machinery. The phrase compresses several cautious scientific questions into one sensational proposition: put on the helmet and meet God.
The actual experiments were subtler. Many reports concerned a vague presence, bodily sensation, fear, sadness or altered sense of space. Media storytelling selected the most dramatic interpretation, while the physical helmet made an abstract hypothesis photogenic. The apparatus therefore became both a research tool and a cultural image of neuroscience’s ambition to explain belief.
The name implies a machine that manufactures God. The research asked a narrower question about whether a particular physical pattern could influence the feeling that somebody else was present.
Safety and ethical caution
Weak fields do not make home experimentation evidence-based
- The Koren helmet and commercial descendants are not established treatments for depression, anxiety, trauma, epilepsy, pain or any other health condition.
- Do not treat online instructions, software files, product claims or testimonials as substitutes for medical-device standards, calibrated equipment or research governance.
- This page intentionally does not provide construction, coil-placement or waveform instructions. Unknown hardware can create electrical, thermal, magnetic and psychological risks that a historical description cannot evaluate.
- People with seizures, implanted electronic or metal devices, neurological or psychiatric conditions, pregnancy, or medication-related vulnerability should not experiment with unregulated stimulation equipment and should seek appropriate clinical advice.
- Darkness, isolation, expectation and altered-state practices can themselves be distressing. A frightening sensed presence may intensify anxiety, paranoia, dissociation or sleep disturbance.
- Researchers should use informed consent, credible sham control, adverse-event monitoring, debriefing and a plan for participants who become distressed.
Medical note: This page is for historical and educational use. It is not a recommendation to purchase, build or use a device and does not replace advice from a qualified healthcare professional.
Selected research and historical sources
Read the evidence directly
- Persinger, M. A. (1983). Religious and mystical experiences as artifacts of temporal lobe function: a general hypothesis.
- Persinger, M. A. (1987). Neuropsychological Bases of God Beliefs.
- Richards, P. M., Persinger, M. A., and Koren, S. A. (1997). Differential entrainment of electroencephalographic activity by weak complex electromagnetic fields.
- Persinger, M. A. (1997). Experimental induction of the “sensed presence” in normal subjects and an exceptional subject.
- Hitt, J. (1999). This Is Your Brain on God. A media history source rather than a controlled study.
- Persinger, M. A., Tiller, S. G., and Koren, S. A. (2000). Experimental simulation of a haunt experience and elicitation of paroxysmal electroencephalographic activity.
- Persinger, M. A. (2001). The neuropsychiatry of paranormal experiences.
- Cook, C. M., and Persinger, M. A. (2002). Experimental facilitation of the sensed presence.
- Tsang, E. W., Koren, S. A., and Persinger, M. A. (2004). Electrophysiological and quantitative EEG measurements after treatment by transcerebral magnetic fields: the Shakti treatment.
- Granqvist, P., et al. (2005). Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak complex magnetic fields.
- Persinger, M. A., and Koren, S. A. (2005). A response to Granqvist et al.
- St-Pierre, L. S., and Persinger, M. A. (2006). Experimental facilitation of the sensed presence is predicted by the specific patterns of the applied magnetic fields, not by suggestibility.
- Arzy, S., et al. (2006). Induction of an illusory shadow person.
- French, C. C., et al. (2009). The “Haunt” project: an attempt to build a “haunted” room by manipulating complex electromagnetic fields and infrasound.
- Gendle, M. H., and McGrath, M. G. (2012). Can the 8-coil Shakti alter subjective emotional experience? A randomized, placebo-controlled study.
- Blanke, O., et al. (2014). Neurological and robot-controlled induction of an apparition.
- Simmonds-Moore, C., et al. (2019). Exceptional experiences following exposure to a sham “God Helmet”.
- Murphy, T. R. Curriculum vitae and self-reported Shakti development timeline. Included as a first-person historical source, not independent validation.
…an unfinished question
Persinger’s programme was daring because it treated an elusive experience as something that might be described, manipulated and measured. The Koren helmet gave that ambition a physical form. Murphy’s Shakti systems carried parts of the idea beyond the originating laboratory and helped keep it in public circulation.
The evidence did not mature into a reliably replicated magnetic-field effect. Yet the central phenomenon did not disappear. Felt presence remains a serious subject in neurology, psychosis research, bereavement studies, sleep science and the study of extreme environments. The most durable legacy of the “God Helmet” may therefore be methodological: extraordinary subjective experiences can enter the laboratory, but a memorable apparatus and a vivid story must never be allowed to substitute for independent evidence.
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