6,486 Studies Reviewed. 85.2% of Original Studies Found Biological Effects. The Evidence is Clear.
Shield Your Body

Note: This study found no significant biological effects under its experimental conditions. We include all studies for scientific completeness.

Brain & Nervous System

902 MHz mobile phone does not affect short term memory in humans.

No Effects Found

Haarala C, Ek M, Bjornberg L, Laine M, Revonsuo A, Koivisto M, Hamalainen H. · 2004

View Original Abstract
Share:

This study found no memory effects from 902 MHz phone radiation, but researchers noted effects might be too small to detect reliably.

Plain English Summary

Summary written for general audiences

Finnish researchers tested whether 902 MHz mobile phone radiation affects short-term memory by having 64 people perform memory tasks while exposed to either real phone radiation or fake exposure. They found no differences in reaction time or accuracy between the two conditions, failing to replicate their earlier study that suggested memory effects. This suggests that mobile phone radiation at this frequency may not significantly impair the type of working memory needed for everyday tasks.

Why This Matters

This study represents an important example of scientific self-correction in EMF research. The researchers attempted to replicate their own previous findings with improved methodology, including double-blind design and multi-center testing, but could not reproduce the memory effects they had initially observed. While this might seem reassuring, the authors themselves acknowledge a crucial limitation: the effects might exist but be too subtle for their testing methods to detect reliably. The reality is that 902 MHz falls within the range of frequencies used by mobile phones, though modern devices typically operate at higher frequencies like 1800-2100 MHz for 3G/4G. What this means for you is that isolated negative studies like this one don't definitively prove safety, especially when the researchers admit their methods may not be sensitive enough to detect real but small effects.

Exposure Information

A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 902 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 902 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Specific exposure levels were not quantified in this study. The study examined exposure from: 902 MHz

Study Details

We studied the effects of an electromagnetic field (EMF) as emitted by a 902 MHz mobile phone on human short term memory. This study was a replication with methodological improvements to our previous study. The improvements included multi-centre testing and a double blind design.

A total of 64 subjects (32 men) in two independent laboratories performed a short term memory task (...

There were no statistically significant differences in performance between the two laboratories. We ...

Cite This Study
Haarala C, Ek M, Bjornberg L, Laine M, Revonsuo A, Koivisto M, Hamalainen H. (2004). 902 MHz mobile phone does not affect short term memory in humans. Bioelectromagnetics. 25(6):452-456, 2004.
Show BibTeX
@article{c_2004_902_mhz_mobile_phone_3058,
  author = {Haarala C and Ek M and Bjornberg L and Laine M and Revonsuo A and Koivisto M and Hamalainen H.},
  title = {902 MHz mobile phone does not affect short term memory in humans.},
  year = {2004},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/15300731/},
}
PubMed: 15300731

Cited By (93 papers)

View all 93 citing papers on Semantic Scholar

Quick Questions About This Study

No, 902 MHz cell phone radiation does not affect short-term memory performance. Finnish researchers tested 64 people doing memory tasks while exposed to real or fake phone radiation and found no differences in reaction time or accuracy between conditions.
The Finnish researchers could not replicate their earlier findings suggesting memory effects from 902 MHz radiation. Their 2004 study with 64 participants found no significant effects, indicating the original results may not be reliable or reproducible.
Haarala's 2004 study tested 902 MHz mobile phone radiation specifically. This frequency was used to examine whether cell phone emissions could affect short-term working memory performance in 64 human participants across two laboratory settings.
64 people participated in the 2004 Finnish study testing 902 MHz mobile phone radiation effects on memory. Researchers exposed participants to either real phone radiation or fake exposure while they performed short-term memory tasks.
Researchers suggest the inability to replicate their 902 MHz memory findings could result from either no actual EMF effects existing or the effects being too small for their testing methods to reliably detect and measure.