8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.
Shield Your Body
Symptoms & Sensitivity

Human perception of illumination with pulsed ultrahigh-frequency electromagnetic energy

Bioeffects Seen

Frey AH, Messenger R · 1973

Share:

Humans can perceive pulsed microwave radiation as phantom sounds, proving direct electromagnetic interaction with biological systems.

Plain English Summary

Summary written for general audiences

This 1973 study found that humans can perceive "sounds" like buzzes and hisses when exposed to pulsed microwave radiation, even though no actual sound waves are present. The perception depended on peak power rather than average power, and both humans and cats experienced this phenomenon during radar field tests.

Why This Matters

This groundbreaking research documented the "microwave auditory effect" - a phenomenon where electromagnetic energy directly stimulates auditory perception without sound waves. What makes this particularly relevant today is that modern wireless devices use similar pulsed signals, though typically at much lower power levels. The study's finding that peak power matters more than average power challenges how we think about EMF safety limits, which often focus on average exposures. While your smartphone operates at far lower power than the radar systems tested, the basic mechanism - pulsed electromagnetic energy affecting human perception - remains the same. This research opened the door to understanding how EMF can directly interact with biological systems in ways we're still discovering.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
Frey AH, Messenger R (1973). Human perception of illumination with pulsed ultrahigh-frequency electromagnetic energy.
Show BibTeX
@article{human_perception_of_illumination_with_pulsed_ultrahigh_frequency_electromagnetic_g6691,
  author = {Frey AH and Messenger R},
  title = {Human perception of illumination with pulsed ultrahigh-frequency electromagnetic energy},
  year = {1973},
  
  
}

Quick Questions About This Study

Yes, this study confirmed humans perceive buzzing and hissing sounds when exposed to pulsed ultrahigh-frequency electromagnetic energy, even though no actual acoustic sound waves are present. The effect occurs through direct electromagnetic stimulation.
Peak power is the primary factor determining perception strength, with pulse width playing a secondary role. Surprisingly, average power levels did not significantly affect whether people could perceive the phantom sounds.
Yes, field tests with radar systems showed that cats also receive and respond to the same low-power electromagnetic energy that causes auditory perception in humans, suggesting this is a broader biological phenomenon.
No, the perceived sounds are not caused by acoustic energy but by direct electromagnetic stimulation. The ultrahigh-frequency electromagnetic energy itself creates the auditory perception without generating traditional sound waves in air.
Radar field tests demonstrated that both humans and cats could detect low-power electromagnetic energy at 1-3 power levels, with human subjects consistently reporting buzzing and hissing sounds during exposure to the pulsed signals.