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Mobile phone ‘talk-mode’ signal delays EEG-determined sleep onset.

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Hung CS, Anderson C, Horne JA, McEvoy P. · 2007

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Mobile phone talk mode delayed sleep onset in this study, even at exposure levels considered safe by current regulations.

Plain English Summary

Summary written for general audiences

Researchers exposed sleep-deprived people to mobile phone signals for 30 minutes, then monitored their brain waves during sleep. Active phone transmissions during "talk mode" significantly delayed deep sleep onset compared to other phone modes, suggesting cell phone use can disrupt natural sleep patterns.

Why This Matters

This controlled study adds important evidence to our understanding of how mobile phone radiation affects sleep quality. The researchers used realistic exposure levels (SAR of 0.133 W/kg) that fall well within current safety limits, yet still found measurable effects on brain activity during sleep onset. What makes this research particularly significant is that it isolated the specific 'talk mode' transmission pattern as the culprit, suggesting that the pulsed nature of active phone calls creates more biological disruption than passive listening or standby modes. The science demonstrates that even brief exposures can alter brain wave patterns in ways that delay restorative sleep. What this means for you is that keeping your phone in active use near your head before bedtime may be interfering with your sleep quality in ways you might not even notice.

Exposure Details

SAR
0.133 , 0.015 , 0.001 W/kg
Source/Device
GSM900 mobile phone
Exposure Duration
30 min

Where This Falls on the Concern Scale

Study Exposure Level in ContextA logarithmic scale showing exposure levels relative to Building Biology concern thresholds and regulatory limits.Study Exposure Level in ContextThis study: 0.133 , 0.015 , 0.001 W/kgExtreme Concern0.1 W/kgFCC Limit1.6 W/kgEffects observed in the Slight Concern range (Building Biology)FCC limit is 1,600x higher than this exposure level

Study Details

We used a GSM900 mobile phone controlled by a base-station simulator and a test SIM card to simulate these three specific modes, transmitted at 12.5% (23 dBm) of maximum power.

At weekly intervals, 10 healthy young adults, sleep restricted to 6 h, were randomly and single-blin...

There was no condition effect for subjective sleepiness. Post-exposure, sleep latency after talk mod...

Cite This Study
Hung CS, Anderson C, Horne JA, McEvoy P. (2007). Mobile phone ‘talk-mode’ signal delays EEG-determined sleep onset. Neurosci Lett. 421(1):82-86, 2007.
Show BibTeX
@article{cs_2007_mobile_phone_talkmode_signal_260,
  author = {Hung CS and Anderson C and Horne JA and McEvoy P. },
  title = {Mobile phone ‘talk-mode’ signal delays EEG-determined sleep onset.},
  year = {2007},
  
  url = {https://www.sciencedirect.com/science/article/abs/pii/S0304394007006003},
}

Quick Questions About This Study

Researchers exposed sleep-deprived people to mobile phone signals for 30 minutes, then monitored their brain waves during sleep. Active phone transmissions during "talk mode" significantly delayed deep sleep onset compared to other phone modes, suggesting cell phone use can disrupt natural sleep patterns.