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Rhesus monkey behavior during exposure to high-peak-power 5.62-GHz microwave pulses.

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D'Andrea JA, Thomas A, Hatcher DJ · 1994

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High-power microwave exposure at 4-6 W/kg immediately impaired cognitive performance in monkeys, suggesting real-time neurological effects above current safety thresholds.

Plain English Summary

Summary written for general audiences

Researchers exposed rhesus monkeys to high-power 5.62 GHz microwave pulses while the animals performed cognitive tasks for food rewards. At exposure levels of 4 and 6 watts per kilogram (W/kg), the monkeys showed significant impairments in their ability to respond correctly, with slower reaction times and fewer earned food rewards. This demonstrates that microwave radiation at these levels can disrupt cognitive performance and behavioral responses in real-time.

Why This Matters

This study provides compelling evidence that microwave radiation can impair cognitive function at specific absorption rates that exceed current safety guidelines but remain within ranges used by some military and industrial applications. The 4-6 W/kg exposure levels that caused behavioral disruption are significantly higher than typical consumer device exposures, which generally produce SAR values under 2 W/kg. However, the immediate nature of these cognitive effects is particularly noteworthy because it demonstrates that EMF exposure can cause measurable neurological impacts during exposure, not just after prolonged periods. The research adds to a growing body of evidence suggesting that current safety standards may not adequately protect against subtle but meaningful effects on brain function and behavior.

Exposure Details

SAR
2, 4, or 6 W/kg
Power Density
56000, 128000, 277000, 518000, 1270000, 2520000 µW/m²
Source/Device
5.62 GHz
Exposure Duration
20 minutes

Exposure Context

This study used 56000, 128000, 277000, 518000, 1270000, 2520000 µW/m² for radio frequency:

This study used 2, 4, or 6 W/kg for SAR (device absorption):

Building Biology guidelines are practitioner-based limits from real-world assessments. BioInitiative Report recommendations are based on peer-reviewed science. Check Your Exposure to compare your own measurements.

Where This Falls on the Concern Scale

Study Exposure Level in ContextStudy Exposure Level in ContextThis study: 56000, 128000, 277000, 518000, 1270000, 2520000 µW/m²Extreme Concern - 1,000 uW/m2FCC Limit - 10M uW/m2Effects observed in the Extreme Concern rangeFCC limit is 179x higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 5.62 GHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 5.62 GHzPower lines50/60 HzCell phones~1 GHz5G mm28 GHzLogarithmic scale

Study Details

The present study investigated Rhesus monkey behavior during exposure to high-peak-power 5.62-GHz microwave pulses.

Four male rhesus monkeys (Macaca mulatta) were trained on an operant task for food pellet reward to ...

Compared to sham exposures, significant alterations of lever responding, reaction time, and earned f...

Cite This Study
D'Andrea JA, Thomas A, Hatcher DJ (1994). Rhesus monkey behavior during exposure to high-peak-power 5.62-GHz microwave pulses. Bioelectromagnetics 15(2):163-176, 1994.
Show BibTeX
@article{ja_1994_rhesus_monkey_behavior_during_920,
  author = {D'Andrea JA and Thomas A and Hatcher DJ},
  title = {Rhesus monkey behavior during exposure to high-peak-power 5.62-GHz microwave pulses.},
  year = {1994},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/8024607/},
}
PubMed: 8024607

Cited By (28 papers)

Quick Questions About This Study

Research shows microwave radiation can impair brain function. A 1994 study found rhesus monkeys exposed to 5.62 GHz microwaves showed slower reaction times and reduced cognitive performance during exposure at higher power levels.
Yes, microwave exposure can cause cognitive impairment. Researchers found monkeys exposed to high-power microwave pulses had significantly slower responses and performed worse on cognitive tasks requiring focus and coordination.
High-frequency microwave radiation can disrupt cognitive performance in real-time. Studies show exposure to 5.62 GHz microwaves at 4-6 watts per kilogram impaired animals' ability to complete memory-based tasks for rewards.
Radar-frequency exposure can impair brain function and behavior. Research demonstrates that microwave pulses similar to radar systems cause measurable decreases in reaction time and task performance in laboratory studies.
Microwave exposure significantly slows reaction times during active exposure. Laboratory studies found animals exposed to 5.62 GHz microwaves showed delayed responses and reduced ability to earn food rewards through cognitive tasks.