Impact of extremely low-frequency magnetic fields on human postural control

Area of Science:

• Biomedical Engineering
• Neuroscience
• Human Physiology

Background:

• Extremely low-frequency (ELF) magnetic fields (MF) are known to modulate human standing balance.
• Systematic investigation of acute balance effects from high flux densities of ELF MF and alternating currents (AC) is lacking.

Purpose of the Study:

• To investigate the acute effects of 50 and 100 mTrms MF and 1.5 mA AC on human standing balance.
• To analyze postural responses using center of pressure (COP) displacement.

Main Methods:

• Twenty-two participants were exposed to MF and AC.
• Postural sway was quantified by analyzing COP path length, area, velocity, and power spectrum.
• Direct current (DC) stimulation served as a positive control.

Main Results:

• DC stimulation demonstrated a significant effect on postural control, as expected.
• No significant effects were observed for time-varying MF or AC stimulations on balance.
• A significant biased stabilization effect was noted in the experimental apparatus, potentially confounding results.

Conclusions:

• Acute exposure to high flux densities of ELF MF and AC did not significantly alter standing balance in this study.
• The custom apparatus may have introduced bias, masking potential real effects.
• Further research with refined methodologies is needed to clarify the balance effects of MF and AC.