Microwave auditory effect
Encyclopedia
The microwave auditory effect, also known as the microwave hearing effect or the Frey effect, consists of audible clicks induced by pulsed/modulated microwave
frequencies. The clicks are generated directly inside the human head without the need of any receiving electronic device. The effect was first reported by persons working in the vicinity of radar
transponders during World War II
. These induced sounds are not audible to other people nearby. The microwave auditory effect was later discovered to be inducible with shorter-wavelength portions of the electromagnetic spectrum
. During the Cold War
era, the American
neuroscientist
Allan H. Frey
studied this phenomenon and was the first to publish information on the nature of the microwave auditory effect.
Dr. Don R. Justesen published "Microwaves and Behavior" in The American Psychologist (Volume 30, March 1975, Number 3).
Research by NASA
in the 1970s showed that this effect occurs as a result of thermal expansion of parts of the human ear around the cochlea
, even at low power density. Later, signal modulation was found to produce sounds or words that appeared to originate intracranially. It was studied for its possible use in communications. Both the US and USSR studied its use in non-lethal weaponry.
Pulsed microwave radiation can be heard by some workers; the irradiated personnel perceive auditory sensations of clicking or buzzing. The cause is thought to be thermoelastic expansion of portions of auditory apparatus. The auditory system response occurs at least from 200 MHz to at least 3 GHz. In the tests, repetition rate of 50 Hz was used, with pulse width between 10–70 microseconds. The perceived loudness was found to be linked to the peak power density instead of average power density. At 1.245 GHz, the peak power density for perception was below 80 mW/cm2. The generally accepted mechanism is rapid (but minuscule, in the range of 10−5 °C) heating of brain by each pulse, and the resulting pressure wave traveling through skull to cochlea
.
The existence of non-lethal weaponry that exploits the microwave auditory effect appears to have been classified "Secret NOFORN" in the USA from (at the latest) 1998, until the declassification on 6 December 2006 of "Bioeffects of Selected Non-Lethal Weaponry" in response to a FOIA
request. Application of the microwave hearing technology could facilitate a private message transmission. Quoting from the above source, "Microwave hearing may be useful to provide a disruptive condition to a person not aware of the technology. Not only might it be disruptive to the sense of hearing, it could be psychologically devastating if one suddenly heard "voices within one's head
".
The technology gained further public attention when a company announced in early 2008 that they were close to fielding a device called MEDUSA
(Mob Excess Deterrent Using Silent Audio) based on the principle.
Electroreception
has also been studied in the animal world. Ritz et al., in Biophysical Journal, hypothesize that transduction of the Earth's geomagnetic field is responsible for the magnetoreception systems of birds. Specifically, they propose that this transduction may take place in a class of photoreceptors known as cryptochrome
s.
, in 1961. In his experiments, the subjects were discovered to be able to hear appropriately pulsed microwave radiation, from a distance of 100 meters from the transmitter. This was accompanied by side effects
such as dizziness
, headaches, and a pins and needles sensation.
Sharp and Grove developed receiverless wireless
voice transmission technologies for the Advanced Research Projects Agency at Walter Reed Army Institute of Research, in 1973. In the above mentioned journal entry to The American Psychologist, Dr. Don Justesen reports that Sharp and Grove were readily able to hear, identify, and distinguish among the single-syllable words for digits between 1 and 10 . Justesen writes, "The sounds heard were not unlike those emitted by persons with artificial larynxes. Communication of more complex words and of sentences was not attempted because the averaged densities of energy required to transmit longer messages would approach the [still] current 10mW/cm² limit of safe exposure." (D.R. Justesen. "Microwaves and Behavior", Am Psychologist, 392(Mar): 391–401, 1975.)
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
frequencies. The clicks are generated directly inside the human head without the need of any receiving electronic device. The effect was first reported by persons working in the vicinity of radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
transponders during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. These induced sounds are not audible to other people nearby. The microwave auditory effect was later discovered to be inducible with shorter-wavelength portions of the electromagnetic spectrum
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
. During the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
era, the American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
neuroscientist
Neuroscientist
A neuroscientist is an individual who studies the scientific field of neuroscience or any of its related sub-fields...
Allan H. Frey
Allan H. Frey
Allan H. Frey is an American neuroscientist known for his research and writing during the Cold War on the nature of the microwave auditory effect, also called the "Frey effect". He worked at General Electric's Advanced Electronics Center at Cornell University...
studied this phenomenon and was the first to publish information on the nature of the microwave auditory effect.
Dr. Don R. Justesen published "Microwaves and Behavior" in The American Psychologist (Volume 30, March 1975, Number 3).
Research by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
in the 1970s showed that this effect occurs as a result of thermal expansion of parts of the human ear around the cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
, even at low power density. Later, signal modulation was found to produce sounds or words that appeared to originate intracranially. It was studied for its possible use in communications. Both the US and USSR studied its use in non-lethal weaponry.
Pulsed microwave radiation can be heard by some workers; the irradiated personnel perceive auditory sensations of clicking or buzzing. The cause is thought to be thermoelastic expansion of portions of auditory apparatus. The auditory system response occurs at least from 200 MHz to at least 3 GHz. In the tests, repetition rate of 50 Hz was used, with pulse width between 10–70 microseconds. The perceived loudness was found to be linked to the peak power density instead of average power density. At 1.245 GHz, the peak power density for perception was below 80 mW/cm2. The generally accepted mechanism is rapid (but minuscule, in the range of 10−5 °C) heating of brain by each pulse, and the resulting pressure wave traveling through skull to cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
.
The existence of non-lethal weaponry that exploits the microwave auditory effect appears to have been classified "Secret NOFORN" in the USA from (at the latest) 1998, until the declassification on 6 December 2006 of "Bioeffects of Selected Non-Lethal Weaponry" in response to a FOIA
Freedom of Information Act (United States)
The Freedom of Information Act is a federal freedom of information law that allows for the full or partial disclosure of previously unreleased information and documents controlled by the United States government. The Act defines agency records subject to disclosure, outlines mandatory disclosure...
request. Application of the microwave hearing technology could facilitate a private message transmission. Quoting from the above source, "Microwave hearing may be useful to provide a disruptive condition to a person not aware of the technology. Not only might it be disruptive to the sense of hearing, it could be psychologically devastating if one suddenly heard "voices within one's head
Auditory hallucination
An auditory hallucination, or paracusia, is a form of hallucination that involves perceiving sounds without auditory stimulus. A common form involves hearing one or more talking voices...
".
The technology gained further public attention when a company announced in early 2008 that they were close to fielding a device called MEDUSA
MEDUSA (weapon)
MEDUSA is a directional, non-lethal weapon designed for crowd control and exploiting the microwave auditory effect. It uses microwave pulses to generate uncomfortably high noise levels in human skulls, bypassing the ears and ear drums.MEDUSA is developed by the Sierra Nevada Corporation.-...
(Mob Excess Deterrent Using Silent Audio) based on the principle.
Electroreception
Electroreception
Electroreception is the biological ability to perceive natural electrical stimuli. It has been observed only in aquatic or amphibious animals, since water is a much better conductor than air. Electroreception is used in electrolocation and for electrocommunication.- Overview :Electroreception is...
has also been studied in the animal world. Ritz et al., in Biophysical Journal, hypothesize that transduction of the Earth's geomagnetic field is responsible for the magnetoreception systems of birds. Specifically, they propose that this transduction may take place in a class of photoreceptors known as cryptochrome
Cryptochrome
Cryptochromes are a class of blue light-sensitive flavoproteins found in plants and animals. Cryptochromes are involved in the circadian rhythms of plants and animals, and in the sensing of magnetic fields in a number of species...
s.
Primary Cold War-era research in the US
The first American to publish on the microwave hearing effect was Allan H. FreyAllan H. Frey
Allan H. Frey is an American neuroscientist known for his research and writing during the Cold War on the nature of the microwave auditory effect, also called the "Frey effect". He worked at General Electric's Advanced Electronics Center at Cornell University...
, in 1961. In his experiments, the subjects were discovered to be able to hear appropriately pulsed microwave radiation, from a distance of 100 meters from the transmitter. This was accompanied by side effects
Adverse effect (medicine)
In medicine, an adverse effect is a harmful and undesired effect resulting from a medication or other intervention such as surgery.An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. If it results from an unsuitable or incorrect dosage or...
such as dizziness
Dizziness
Dizziness refers to an impairment in spatial perception and stability. The term is somewhat imprecise. It can be used to mean vertigo, presyncope, disequilibrium, or a non-specific feeling such as giddiness or foolishness....
, headaches, and a pins and needles sensation.
Sharp and Grove developed receiverless wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...
voice transmission technologies for the Advanced Research Projects Agency at Walter Reed Army Institute of Research, in 1973. In the above mentioned journal entry to The American Psychologist, Dr. Don Justesen reports that Sharp and Grove were readily able to hear, identify, and distinguish among the single-syllable words for digits between 1 and 10 . Justesen writes, "The sounds heard were not unlike those emitted by persons with artificial larynxes. Communication of more complex words and of sentences was not attempted because the averaged densities of energy required to transmit longer messages would approach the [still] current 10mW/cm² limit of safe exposure." (D.R. Justesen. "Microwaves and Behavior", Am Psychologist, 392(Mar): 391–401, 1975.)
Peaceful applications
A 1998 patent describes a device that can scare off birds from wind turbines, aircraft, and other sensitive installations by way of microwave energy pulses. Using frequencies from 1 GHz to about 40 GHz, the warning system generates pulses of milliseconds duration, which are claimed to be sensed by the birds' auditory systems. It is believed this may cause them to veer away from the protected object.Patented applications
- Flanagan GP. “Nervous System Excitation Device” USPTO granted 7/16/68.
- Puharich HK and Lawrence JL. “Hearing systems” USPTO granted 12/21/71.
- Malech RG. “Apparatus and method for remotely monitoring and altering brain waves” USPTO granted 4/20/76.
- Stocklin PL. “Hearing device” USPTO granted 8/22/89.
- Brunkan WB. “Hearing system” USPTO granted 10/31/89.
- Thijs VMJ. Application #WO1992NL0000216 “Hearing Aid Based on Microwaves” World Intellectual Property Organization Filed 1992-11-26, Published 1993-06-10.
- Mardirossian A. “Communication system and method including brain wave analysis and/or use of brain activity” USPTO granted 1/4/00.
- O'Loughlin, James P. and Loree, Diana L. "Method and device for implementing the radio frequency hearing effect" USPTO granted 22-OCT-2002.
See also
- BiophotonBiophotonA biophoton , synonymous with ultraweak photon emission, low-level biological chemiluminescence, ultraweak bioluminescence, dark luminescence and other similar terms, is a photon of light emitted from a biological system and detected by biological probes as part of the general weak electromagnetic...
- Brain-computer interfaceBrain-computer interfaceA brain–computer interface , sometimes called a direct neural interface or a brain–machine interface , is a direct communication pathway between the brain and an external device...
- Cosmic ray visual phenomenaCosmic ray visual phenomenaCosmic ray visual phenomena, also referred to as phosphenes or "light flashes", are spontaneous flashes of light visually perceived by astronauts outside the magnetosphere of the Earth, such as during the Apollo program. Researchers believe that cosmic rays are responsible for these flashes of...
- ElectroreceptionElectroreceptionElectroreception is the biological ability to perceive natural electrical stimuli. It has been observed only in aquatic or amphibious animals, since water is a much better conductor than air. Electroreception is used in electrolocation and for electrocommunication.- Overview :Electroreception is...
External links
- Seaman, Ronald L., “Transmission of microwave-induced intracranial sound to the inner ear is most likely through cranial aqueducts,“ Mckesson Bioservices Corporation, Wrair US Army Medical Research Detachment. (PDFPortable Document FormatPortable Document Format is an open standard for document exchange. This file format, created by Adobe Systems in 1993, is used for representing documents in a manner independent of application software, hardware, and operating systems....
) - Lin, J.C., 1980, “The microwave auditory phenomenon,“ Proceedings of the IEEE, 68:67–73. Navy-NSF-supported research.
- Lin, JC., "Microwave auditory effect- a comparison of some possible transduction mechanisms". J Microwave Power. 1976 Mar;11(1):77–81. 1976.
- Guy, A.W., C.K. Chou, J.C. Lin and D. Christensen, 1975, Microwave induced acoustic effects in mammalian auditory systems and physical materials, Annals of New York Academy of Sciences, 247:194–218
- Fist, Stewart, "Australian exposure standards". Crossroads, The Australian, March 1999.
- Microwave auditory effects and applications, James C. Lin; Publisher: Thomas; ISBN 0-398-03704-3
- Malech, Robert G., " : Apparatus and method for remotely monitoring and altering brain waves". April 20, 1976.
- McMurtrey, John J., "Inner Voice, Target Tracking, and Behavioral Influence Technologies". Nov. 14, 2004.
- US Department of Defense, Air Force Research Laboratory comprehensive review on RFR-auditory effect in humans
- Thijs VMJ. Application #WO1992NL0000216 “Hearing Aid Based on Microwaves” World Intellectual Property Organization Filed 1992-11-26, Published 1993-06-10.
- Kohn B. “Communicating Via the Microwave Auditory Effect” Defense Department Awarded SBIR Contract # F41624-95-C9007, 1993.
- “Auditory Responses to Pulsed Radiofrequency Energy” Bioelectromagnetics Suppl 8: S162-73, 2003.
- Suppes P, Lu Z, and Han B. “Brain wave recognition of words” Proc Natl Acad Sci 94: 14965-69, 1997.
- Suppes P, Han B, and Lu Z. “Brain-wave recognition of sentences” Proc Natl Acad Sci 95: 15861-66, 1998.
- Assadullahi R and Pulvermuller F. “Neural Network Classification of Word Evoked Neuromagnetic Brain Activity” In: Wermter S, Austin J, and Willahaw D (eds.) Lecture Notes in Artificial Intelligence: Emergent Neurocomputational Architectures Based on Neuroscience Heidelberg Springer, p 311-20, 2001.
- Smith C. “On the Need for New Criteria of Diagnosis of Psychosis in the Light of Mind Invasive Technology” J Psycho-Social Studies 2(2) #3, 2003.
- McMurtrey JJ. “Microwave Bioeffect Congruence with Schizophrenia” In press, 2003.