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Brain & Nervous System113 citations

Effects of a 902 MHz mobile phone on cerebral blood flow in humans: a PET study.

No Effects Found

Haarala C, Aalto S, Hautzel H, Julkunen L, Rinne JO, Laine M, Krause B, Hamalainen H. · 2003

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This study found brain blood flow changes during phone use, but researchers attributed them to subtle sounds rather than EMF radiation.

Plain English Summary

Summary written for general audiences

Researchers used PET brain scans to measure blood flow in 14 people while they were exposed to a 902 MHz mobile phone signal. They found decreased blood flow in the auditory areas of the brain, but not in the areas where EMF exposure was strongest. The researchers concluded this was likely due to subtle sounds from the phone rather than the electromagnetic radiation itself.

Why This Matters

This study highlights a critical challenge in EMF research: distinguishing true biological effects from experimental artifacts. While the researchers found changes in brain blood flow during phone exposure, they correctly identified that these changes occurred in auditory regions rather than areas of maximum EMF exposure, suggesting the phone emitted subtle sounds that influenced the results. This demonstrates the importance of rigorous experimental design in EMF studies. The reality is that many early mobile phone studies faced similar methodological challenges, making it essential to look at the broader body of evidence rather than individual studies. What this means for you is that well-designed studies with proper controls remain crucial for understanding EMF's true biological impacts.

Study Details

The aim of this study is to imvestigate Effects of a 902 MHz mobile phone on cerebral blood flow in humans: a PET study.

Fourteen healthy right-handed subjects were scanned using PET with a [15O]water tracer during exposu...

Exposure to an active mobile phone produced a relative decrease in regional cerebral blood flow (rCB...

Therefore, it is not reasoned to attribute this finding to the EMF emitted by the phone. Further study on human rCBF during exposure to EMF of a mobile phone is needed.

Cite This Study
Haarala C, Aalto S, Hautzel H, Julkunen L, Rinne JO, Laine M, Krause B, Hamalainen H. (2003). Effects of a 902 MHz mobile phone on cerebral blood flow in humans: a PET study. Neuroreport. 14(16):2019-2023, 2003.
Show BibTeX
@article{c_2003_effects_of_a_902_3057,
  author = {Haarala C and Aalto S and Hautzel H and Julkunen L and Rinne JO and Laine M and Krause B and Hamalainen H.},
  title = {Effects of a 902 MHz mobile phone on cerebral blood flow in humans: a PET study.},
  year = {2003},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/14600490/},
}
PubMed: 14600490

Cited By (113 papers)

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Quick Questions About This Study

A 2003 PET scan study found that 902 MHz mobile phone signals did not significantly affect brain blood flow. While researchers detected decreased blood flow in auditory brain areas, they concluded this was likely caused by subtle phone sounds rather than electromagnetic radiation itself.
Yes, PET brain scans can measure blood flow changes during EMF exposure. A 2003 study using PET scans on 14 people exposed to 902 MHz signals found blood flow changes in auditory areas, but researchers attributed this to phone sounds rather than electromagnetic effects.
The 2003 Haarala study found decreased blood flow in auditory brain regions rather than areas receiving maximum EMF exposure. Researchers concluded this pattern indicated the changes were caused by subtle auditory signals from the active phone, not electromagnetic radiation.
The 2003 PET study identified specific brain regions receiving maximum EMF exposure from 902 MHz mobile phones. Importantly, these high-exposure areas showed no blood flow changes, leading researchers to conclude electromagnetic radiation didn't cause the observed effects.
Research suggests active mobile phones produce subtle auditory signals that can affect brain blood flow. A 2003 study found decreased blood flow in auditory brain areas during 902 MHz phone exposure, which researchers attributed to these sounds rather than electromagnetic radiation.