Effects of an ELF (50 Hz, 1 mT) electromagnetic field (EMF) on concentration in visual attention, perception and memory including effects of EMF sensitivity.

Toxicology letters · 1998 · Mixed · Low evidence

← Research stream

MixedLow evidencePaper 5378

Study snapshot

PublicationToxicology letters · 1998

Study typeother

Reported directionMixed

Evidence ratingLow

Abstract

To investigate psychological effects of an extremely low frequency (ELF)-electromagnetic field (EMF), an experiment with three conditions was designed. EMF field of 50 Hz and 1 mT accompanied by 45 dB SPL noise (EMF + noise), noise, and control. A group of 66 subjects (Ss) participated in the control and in one of the experimental conditions. The sequence of conditions (expositions) was balanced. Expositions were double-blind (except for the obvious control), lasted 1 h and were separated by a 1 h pause. During exposition Ss (three by three) performed tests on attention, perception, memory and filled out a psychological questionnaire. Statistical analysis (one-tailed probability) showed less attention (P < 0.05), perception (P < 0.05) and memory performance (P < 0.1) in Ss exposed to EMF + noise compared with control, whereas for noise versus control no difference was found. Comparing EMF + noise versus noise related to control, reduced perception, less memory performance and more discomfort was observed (P < 0.1). Dividing Ss according to their self-rated sensitivity to EMF, all differences disappeared in the low sensitivity group (N = 30) and were pronounced in sensitive Ss (N = 36). Results indicate an immediate reduction of cognitive performance in attention, perception and memory performance by a 50 Hz EMF of 1 mT. These effects seem to be modulated by the self-perception of sensitivity to EMF.

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

PopulationHuman subjects

Sample size66

ExposureELF · 0.05 MHz · 1 h

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

In a double-blind experiment with three conditions (EMF+noise, noise, control), participants exposed to 50 Hz, 1 mT EMF accompanied by 45 dB SPL noise showed reduced attention and perception (P<0.05) and reduced memory performance (P<0.1) versus control; noise alone did not differ from control. When stratified by self-rated EMF sensitivity, differences disappeared in the low-sensitivity group (N=30) and were more pronounced in sensitive participants (N=36).

Outcomes measured

Attention (visual attention/concentration)
Perception
Memory performance
Discomfort (questionnaire)
Self-rated EMF sensitivity (effect modifier)

Limitations

Exposure condition combined EMF with noise (EMF+noise), complicating attribution to EMF alone
Control condition not blinded ("obvious control")
Statistical analysis used one-tailed probability
Some reported effects were only marginal (e.g., P<0.1)
Participants were tested in groups of three during exposure

View raw extracted JSON

{
  "study_type": "other",
  "exposure": {
    "band": "ELF",
    "source": null,
    "frequency_mhz": 0.05,
    "sar_wkg": null,
    "duration": "1 h"
  },
  "population": "Human subjects",
  "sample_size": 66,
  "outcomes": [
    "Attention (visual attention/concentration)",
    "Perception",
    "Memory performance",
    "Discomfort (questionnaire)",
    "Self-rated EMF sensitivity (effect modifier)"
  ],
  "main_findings": "In a double-blind experiment with three conditions (EMF+noise, noise, control), participants exposed to 50 Hz, 1 mT EMF accompanied by 45 dB SPL noise showed reduced attention and perception (P<0.05) and reduced memory performance (P<0.1) versus control; noise alone did not differ from control. When stratified by self-rated EMF sensitivity, differences disappeared in the low-sensitivity group (N=30) and were more pronounced in sensitive participants (N=36).",
  "effect_direction": "mixed",
  "limitations": [
    "Exposure condition combined EMF with noise (EMF+noise), complicating attribution to EMF alone",
    "Control condition not blinded (\"obvious control\")",
    "Statistical analysis used one-tailed probability",
    "Some reported effects were only marginal (e.g., P<0.1)",
    "Participants were tested in groups of three during exposure"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "ELF",
    "50 Hz",
    "1 mT",
    "noise",
    "double-blind",
    "attention",
    "perception",
    "memory",
    "cognitive performance",
    "EMF sensitivity",
    "discomfort"
  ],
  "suggested_hubs": [
    {
      "slug": "occupational-exposure",
      "weight": 0.25,
      "reason": "Study involves ELF (50 Hz) exposure at 1 mT, relevant to contexts where such fields may occur, though no specific setting is stated."
    }
  ]
}

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: 10.1016/s0378-4274(98)00096-4
PubMed: 9820691

Read the original paper →

Related papers

← Back to the Research Library