Exposure to pulse-modulated radio frequency electromagnetic fields affects regional cerebral blood flow.

The European journal of neuroscience · 2005 · Mixed · Low evidence

← Research stream

MixedLow evidencePaper 5194

Study snapshot

PublicationThe European journal of neuroscience · 2005

Study typeother

Reported directionMixed

Evidence ratingLow

Abstract

We investigated the effects of radio frequency electromagnetic fields (RF EMF) similar to those emitted by mobile phones on waking regional cerebral blood flow (rCBF) in 12 healthy young men. Two types of RF EMF exposure were applied: a 'base-station-like' and a 'handset-like' signal. Positron emission tomography scans were taken after 30 min unilateral head exposure to pulse-modulated 900 MHz RF EMF (10 g tissue-averaged spatial peak-specific absorption rate of 1 W/kg for both conditions) and sham control. We observed an increase in relative rCBF in the dorsolateral prefrontal cortex on the side of exposure. The effect depended on the spectral power in the amplitude modulation of the RF carrier such that only 'handset-like' RF EMF exposure with its stronger low-frequency components but not the 'base-station-like' RF EMF exposure affected rCBF. This finding supports our previous observation that pulse modulation of RF EMF is necessary to induce changes in the waking and sleep EEG, and substantiates the notion that pulse modulation is crucial for RF EMF-induced alterations in brain physiology.

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeother

Effect directionmixed

Population12 healthy young men

Sample size12

ExposureRF · 900 MHz · 1 W/kg · 30 min unilateral head exposure

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

After 30 min unilateral head exposure to pulse-modulated 900 MHz RF EMF (10 g tissue-averaged spatial peak SAR 1 W/kg), relative rCBF increased in the dorsolateral prefrontal cortex on the side of exposure. The increase was observed for the handset-like signal (stronger low-frequency components in amplitude modulation) but not for the base-station-like signal, compared with sham.

Outcomes measured

waking regional cerebral blood flow (rCBF)
relative rCBF in dorsolateral prefrontal cortex
comparison of handset-like vs base-station-like pulse-modulated signals

Limitations

Small sample size (12 participants)
Participants were limited to healthy young men

View raw extracted JSON

{
  "study_type": "other",
  "exposure": {
    "band": "RF",
    "source": "mobile phone",
    "frequency_mhz": 900,
    "sar_wkg": 1,
    "duration": "30 min unilateral head exposure"
  },
  "population": "12 healthy young men",
  "sample_size": 12,
  "outcomes": [
    "waking regional cerebral blood flow (rCBF)",
    "relative rCBF in dorsolateral prefrontal cortex",
    "comparison of handset-like vs base-station-like pulse-modulated signals"
  ],
  "main_findings": "After 30 min unilateral head exposure to pulse-modulated 900 MHz RF EMF (10 g tissue-averaged spatial peak SAR 1 W/kg), relative rCBF increased in the dorsolateral prefrontal cortex on the side of exposure. The increase was observed for the handset-like signal (stronger low-frequency components in amplitude modulation) but not for the base-station-like signal, compared with sham.",
  "effect_direction": "mixed",
  "limitations": [
    "Small sample size (12 participants)",
    "Participants were limited to healthy young men"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "radio frequency electromagnetic fields",
    "RF EMF",
    "mobile phone",
    "pulse modulation",
    "900 MHz",
    "specific absorption rate",
    "SAR",
    "positron emission tomography",
    "PET",
    "regional cerebral blood flow",
    "rCBF",
    "dorsolateral prefrontal cortex",
    "handset-like",
    "base-station-like",
    "sham control"
  ],
  "suggested_hubs": [
    {
      "slug": "who-icnirp",
      "weight": 0.2,
      "reason": "Experimental study of RF EMF exposure parameters relevant to human exposure guidelines (frequency and SAR)"
    }
  ]
}

AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1111/j.1460-9568.2005.03929.x
PubMed: 15787706

Read the original paper →

Related papers

← Back to the Research Library