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Mobile Phones exposure induces changes of Contingent Negative Variation in humans.

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de Tommaso M, Rossi P, Falsaperla R, Francesco VD, Santoro R, Federici A. · 2009

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Cell phones alter brain electrical activity through both radio waves and low-frequency magnetic fields from internal circuits.

Plain English Summary

Summary written for general audiences

Researchers tested how 900 MHz cell phone signals affect brain electrical activity by measuring a specific brainwave pattern called contingent negative variation (CNV) in 10 volunteers. They found that both active phones and sham phones (with internal circuits running but no RF emission) reduced brain arousal and expectation responses compared to phones that were completely off. The study suggests that both the GSM radio signal and the low-frequency magnetic fields from the phone's battery and circuits can alter normal brain function.

Why This Matters

This study reveals something important that most EMF research overlooks: it's not just the radio frequency radiation from your phone that affects your brain. The researchers found that even when the RF signal was blocked, phones still altered brainwave patterns simply from their internal electrical circuits and battery-generated magnetic fields. This finding challenges the narrow focus on SAR values and RF exposure alone. What this means for you is that your phone may be influencing your brain's electrical activity through multiple pathways - the wireless signal everyone talks about, plus the low-frequency fields that exist whenever the device is powered on. While this was a small study of just 10 people, it adds to growing evidence that our devices interact with our biology in ways we're only beginning to understand.

Exposure Information

A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 900 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 900 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Specific exposure levels were not quantified in this study. The study examined exposure from: 900 MHz

Study Details

The aim of the present study was the evaluation of initial contingent negative variation (iCNV) changes, induced by 900 MHz GSM exposure, in a double blind design in healthy volunteers, subjected to a threefold experimental condition, EXPOSED (A), a real GSM phone emitting electromagnetic power, SHAM (B), a real phone where the electromagnetic power was dissipated on an internal load and OFF (C), a phone completely switched-off.

Ten healthy right-handed volunteers were evaluated. The CNV was recorded during a 10 min time interv...

The iCNV amplitude decreased and habituation increased during both A and B conditions, compared with...

Cite This Study
de Tommaso M, Rossi P, Falsaperla R, Francesco VD, Santoro R, Federici A. (2009). Mobile Phones exposure induces changes of Contingent Negative Variation in humans. Neurosci Lett.464(2):79-83, 2009.
Show BibTeX
@article{m_2009_mobile_phones_exposure_induces_2023,
  author = {de Tommaso M and Rossi P and Falsaperla R and Francesco VD and Santoro R and Federici A.},
  title = {Mobile Phones exposure induces changes of Contingent Negative Variation in humans.},
  year = {2009},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/19699778/},
}
PubMed: 19699778

Cited By (26 papers)

Quick Questions About This Study

Yes, a 2009 study found that 900 MHz cell phone signals significantly reduced contingent negative variation (CNV) brain wave patterns in 10 volunteers. Both active phones and phones with internal circuits running decreased brain arousal and expectation responses compared to completely powered-off phones.
Yes, research shows that cell phones can alter brain electrical activity even without RF transmission. A study found that phones with active internal circuits but no radio signals still reduced brain arousal patterns, suggesting low-frequency magnetic fields from batteries and circuits affect brain function.
Yes, 900 MHz GSM signals reduced brain arousal and expectation responses in a controlled study. Researchers measured contingent negative variation brain waves and found decreased amplitude and increased habituation during phone exposure, indicating reduced brain alertness to warning stimuli.
Research suggests yes. A 2009 study found that both GSM radio signals and extremely low frequency magnetic fields from phone batteries and internal circuits altered normal brain electrical activity, specifically reducing contingent negative variation responses across the scalp.
Surprisingly, no significant difference was found based on phone placement. While phones were positioned on the left side of participants' heads, the reduction in contingent negative variation brain wave amplitude occurred diffusely across the entire scalp, not just the exposed side.