Evidence of a Nonlinear Human Magnetic Sense

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Evidence of a Nonlinear Human Magnetic Sense
Simona Carrubba and Andrew Marino Louisiana
State University Health Sciences
Center Department of Orthopaedic
Surgery Shreveport, LA
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Summary

• Model for detecting EMFs?
• Sensory transduction
• Evoked potentials (EPs)
• Nonlinear magnetosensory EPs

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How Should the EMF Interaction Be Modeled?
Proposed theories Sensory perception
Becker Marino Electromagnetism Life,
1980. Marino Bioelectrochem., 1993.
Sonnier Marino Electro - Magnetobiology,
2001. Marino et al. Clin. Neurophysiol., 2004.
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Sensory Transduction Hypothesis
Brain
Afferent Signal
Sensory Cell
EMF
Odorant molecule
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Experimental Rationale
All known sensory stimuli
Onset (Off-On transition) Offset (On-Off
transition) Latency 50-500 ms
Evoked Potentials
If magnetic field is sensed Evoked potential

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Our Definition of Nonlinearity
X(t) Sensory stimulus (applied N times)
S
X(t)
Y(t)
Increase (??N) X-Y is LINEAR Decrease X-Y is
NONLINEAR
Snoise(N)
Marino et al, BEMS, 2001 - Marino et al, BEMS,
2003
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Homogeneity of Magnetic Field(2 gauss RMS, 60 Hz)
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Experimental Procedure
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Experimental Design
N50 7-s trials
Onset epoch (0.03-1 s) Offset epoch
(2.03-3 s) Control epoch (5.03-6 s)
Linear analysis V(t) Nonlinear Analysis V(t)
R(t)
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Recurrence Quantification Analysis
Carrubba et al. J. Neurosci. Methods, 2006 (in
press)
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Effect of Field-Onset on EEG Time Series
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Effect of Field-Onset onR(t) Time Series
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Effect of Field-Onset onR(t) Time Series
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Detection of Magnetic Fields
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Effect of Field Onset on R
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Effect of Field Offset on R
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Evidence of Nonlinear Characteristics
ofMagnetosensory Evoked Potentials
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Summary of Results
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Conclusion

• Human Magnetic Sense
• Nonlinear