Frey Auditory Effect
The Frey Effect — also known as microwave auditory phenomenon — is the ability to perceive sound without acoustic wave propagation, triggered by pulsed microwave exposure.
Mechanism of Action
Microwave pulses produce rapid thermoelastic expansion in brain tissue. This expansion generates acoustic pressure waves, which are detected by the cochlea and interpreted by the brain as “sound.”
Key characteristics:
- No external sound is emitted
- Perception is typically described as clicks, buzzes, or speech-like bursts
- Time-locked to the pulse train
- Confirmed in both human and animal studies
Historical Use
- Documented in research by Allan H. Frey in the 1960s
- Explored by military and intelligence agencies for silent communication
- Cited in declassified U.S. Army and DARPA reports
Relevance to Disruption Fields
The Frey Effect may be leveraged for:
- Covert symbolic injection (via pulses interpreted as internal thought)
- Sleep disruption (clicking/buzzing while falling asleep)
- Entrainment of subvocal behavior
- Undetectable field-level harassment
This method requires line-of-sight, pulsed modulation, and typically narrow beamwidth.