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THE EFFECTS OF LOW LEVEL MICROWAVE IRRADIATION UPON REFLEXIVE, OPERANT, AND DISCRIMINATION BEHAVIORS OF THE RAT

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Nancy Williams King · 1969

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1969 study found 2450 MHz microwave radiation affected rat behavior even within 'safe' exposure limits.

Plain English Summary

Summary written for general audiences

This 1969 study exposed rats to 2450 MHz microwave radiation (the same frequency used in microwave ovens) while they performed behavioral tasks involving tongue-licking responses. The researchers found that the microwave exposure affected the rats' ability to perform learned behaviors, even at levels considered 'safe' by 1960s standards.

Why This Matters

This pioneering study from 1969 deserves attention because it demonstrated behavioral effects from microwave radiation at the exact frequency (2450 MHz) that powers your microwave oven today. The researchers specifically tested levels around the 10 mW/cm² safety limit that was considered protective at the time. What makes this particularly relevant is that modern Wi-Fi routers, while operating at lower power levels, use this same 2.45 GHz frequency band. The study's focus on behavioral changes rather than just tissue heating was ahead of its time. While we can't directly extrapolate from rat behavior to human cognition, this early research suggested that microwave radiation could affect nervous system function through mechanisms beyond simple thermal heating. The fact that measurable behavioral changes occurred within the supposed 'safety' limits raises questions about whether thermal-based exposure standards adequately protect against all biological effects.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
Nancy Williams King (1969). THE EFFECTS OF LOW LEVEL MICROWAVE IRRADIATION UPON REFLEXIVE, OPERANT, AND DISCRIMINATION BEHAVIORS OF THE RAT.
Show BibTeX
@article{the_effects_of_low_level_microwave_irradiation_upon_reflexive_operant_and_discri_g7109,
  author = {Nancy Williams King},
  title = {THE EFFECTS OF LOW LEVEL MICROWAVE IRRADIATION UPON REFLEXIVE, OPERANT, AND DISCRIMINATION BEHAVIORS OF THE RAT},
  year = {1969},
  
  
}

Quick Questions About This Study

The study used 2450 MHz microwave radiation, which is the same frequency used in microwave ovens today. This frequency is also part of the 2.4 GHz band used by Wi-Fi routers and Bluetooth devices.
Researchers trained rats to perform tongue-licking responses on a photo-operandum (light-activated device) to receive liquid rewards. They then exposed the rats to microwave radiation while monitoring changes in their learned behavioral patterns.
Yes, the study used a modified Tappan electronic range (microwave oven) in a closed-space situation. The researchers had to develop special equipment that could function properly inside the microwave field during behavioral testing.
The study was innovative because it measured real-time behavioral changes during microwave exposure, rather than just looking for tissue damage afterward. The researchers had to create custom equipment that could operate inside microwave fields.
The study used both 60 Hz and 12 Hz modulation of the 2450 MHz carrier frequency. While specific results aren't detailed in the abstract, this modulation approach suggests researchers were investigating whether pulsing patterns influenced biological effects.