The microwave auditory effect, also known as the microwave hearing effect or the Frey effect, consists of audible clicks (or, with speech modulation, spoken words) 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. 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.
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 the auditory apparatus. Competing theories explain the results of interferometric holography tests differently.
In 2003–04, the WaveBand Corp. had a contract from the U.S. Navy for the design of a MAE system they called MEDUSA (Mob Excess Deterrent Using Silent Audio) intended to remotely, temporarily incapacitate personnel. The project was cancelled in 2005.
Primary Cold War-era research in the U.S.
The first American to publish on the microwave hearing effect was Allan H. Frey, 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.
A decade later, an overview of radiation impacts on human perceptions cited investigations at the Walter Reed Army Institute of Research that demonstrated ‘receiverless’ wireless voice transmission via microwaves. However the radiation levels approached the (then current) 10mW/cm² limit of safe exposure.
Conspiracy theories
Numerous individuals suffering from auditory hallucinations, delusional disorders or other mental illness have claimed that government agents use forms of mind control technologies based on microwave signals to transmit sounds and thoughts into their heads as a form of electronic harassment, referring to the technology as “voice to skull” or “V2K”.
There are extensive online support networks and numerous websites maintained by people fearing mind control. California psychiatrist Alan Drucker has identified evidence of delusional disorders on many of these websites and other psychologists are divided over whether such sites reinforce mental troubles or act as a form of group social support.
Psychologists have identified many examples of people reporting ‘mind control experiences’ (MCEs) on self-published web pages that are “highly likely to be influenced by delusional beliefs”. Common themes include “Bad Guys” using “psychotronics” and “microwaves”, frequent mention of the CIA’s MKULTRA project and frequent citing of a scientific paper entitled “Human auditory system response to modulated electromagnetic energy”.