sleepless in bioelectromagnetics: the effects of rf emf on...
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Sleepless in Bioelectromagnetics:Unravelling the Effects of RF EMF on the Brain
Sarah LoughranAustralian Centre for Electromagnetic Bioeffects Research
Wollongong University
Alessandro Chiabrera LectureBioEM 2016, Ghent, Belgium
• PhD (2004‐2007)– Swinburne University of Technology, Melbourne, Australia
• “Effects of RF EMF on sleep, brain activity, and melatonin”
• Postdoctoral Fellow (2008‐2012)– University of Zürich, Switzerland
• Marie Curie Fellowship• Series of studies investigating underlying mechanisms
of effects of EMF on brain activity during sleep• Basic and clinical research
– Sleep and brain activity in patients in a vegetativeor minimal conscious state
• Current Research (2013‐)– University of Wollongong
• Further develop research on RFBioeffects; Basic sleep research
– Well equipped new laboratories• EEG• Sleep
– Strong links with standards/policy
Research Background
Research Focus
• Past Research– Determining effects of electromagnetic fields on human health
and the brain– Understanding underlying neurobiological mechanisms of RF
EMF influence on the brain• Current and Future Research
– Extending and expanding on previous work on determining effects and mechanisms of RF EMF on health and the brain
• Non‐RF Research– Feeds into improving and understanding human
neurophysiology, and sleep, more generally
Mobile Phones and Health: An Increasingly Prominent Issue
• Increasing mobile phone use → increase in concern and demand for scientific research
• Particular focus on potential effects of RF EMF on the human brain– Possibility of biological effects
below current exposure limits/guidelines
• Currently no biophysical mechanisms capable of justifying these concerns
Mobile Phones and Health: What is the Issue?
Mobile Phones and Health: Why study sleep?
• Incredibly important part of daily life– We spend 1/3 of our lives
sleeping!
• Alterations in sleep have large and widespread ramifications for health, wellbeing, and performance
• Important for development
• Simple, non‐invasive technique that reflects synchronous activity in cortical neurons
• Well‐characterised– Correlated with
vigilance state and cognitive functioning/processing during waking
– Reflects different stages of sleep
(non
-RE
M) s
leep
Aeschbach (1995)
Mobile Phones and Health: Addressing the Issue – Why Use EEG?
NREM SleepWaking
Napflin et al. 2007 Buckelmüller et al., 2006
Why Use the EEG?: High Intra‐Individual Stability
RF EMF:Effects on the Sleeping Brain
Early Report of Effects on Sleep
Klaus Mann & Joachim Röschke
Early Reports:Effects on Sleep EEG and Sleep Architecture
Consistent Effects:RF EMF Exposure and the Sleep EEG
Loughran et al., 2005
RF EMF Exposure Effects:Independently Replicated
Methodological Improvements
1) More ecologically valid exposure
2) Large sample size3) Accounted for
multiple comparisons
N = 50
RF EMF Exposure Effects:Sensitive to Individual Variability
Loughran et al., 2012
1) Consistent effects, but different EEG frequencies• Physiological differences?• Different responses to exposure?
2) Results show impact of individual variability
Absolute Power Spectra Relative Power Spectra
Schmid*, Loughran*, et al., 2012
Underlying Mechanisms of RF EMF Sleep EEG Effects:Pulse Modulation Characteristics
Sleep (All Night) Sleep (Last Third of Night)
Loughran et al., in prep
Underlying Mechanisms of RF EMF Sleep EEG Effects:Site of Interaction
RF EMF and the Brain:Major Uncertainties, Research Gaps
& Current Research
RF EMF and the Brain: Consistent Effects, Consequences & Unknowns
• We know there is an effect on neural activity, however:– To date no demonstration of functional significance– Underlying neurobiological mechanisms remain unknown
• General belief that the energy emitted is too small for a thermal response• Sometimes argued that if there are non‐thermal effects then it appears that
these are not taken into account by current standards and guidelines– As the only known RF biophysical mechanism (i.e. thermal) cannot
currently explain this effect, it leaves RF Health Standards in doubt– Lack of understanding raises the possibility that there are concomitant
effects that do impact on health, but that are yet to be assessed • Problematic for risk communication
– Relevance to health, long‐term effects, and possiblesensitive populations (e.g. children)???
RF EMF and the Brain: Sensitivity in Adolescence (Waking EEG)
Loughran et al., 2013
Current Research: RF EMF and Sleep in Children and Adolescents
Current Research: Preliminary Results
Average Spectral Power Individual Data
EEG Pow
er (
V2)
0.3
0.4
0.5
0.6
0.7
0.8
0.9
sham low high0.400
0.500
0.600
0.700
0.800
0.900
sham low high
Sham = No ExposureLow = 0.35 W/KgHigh = 1.4 W/Kg Loughran et al., data collection ongoing
Current Research: Determine whether RF EMF within exposure limits affects thermoregulation
Thermal Perfusion Suit, Finger Temp, Laser Doppler, Auditory Canal, Skin Temp, MAP, EEG, Cognition
Current Research: Replicated effect on EEG alpha activity
‐0.15
‐0.10
‐0.05
0.00
0.05
0.10
0.15
0.20
0.25
0.30
Sham
Low (1W/Kg)
High (2W/Kg)
EE
G A
lpha
Pow
er (Z
-Sco
res)
Sham Low High
p = 0.01 Loughran et al., in prep
Loughran et al., in prep
Current Research: Determine whether RF EMF within exposure limits affects thermoregulation
Results Suggest:
1) RF EMF within ICNIRP limits engages thermoregulatory processes
2) No evidence that RF EMF‐induced EEG brain activity changes are non‐thermal in nature
Complementary non‐EMF Research: Characterising brain activity in altered states of consciousness
Vegetative State Patient
Healthy Adult
Other Current/Planned Research:RF EMF• Thermoregulatory Mechanisms
1. Is the RF‐thermoregulatory change due to core body temp change?
2. Does equivalent thermoregulatory change, temperature at skin, or temperature at cortex (applied/induced via non‐RF sources, e.g. thermal perfusion suit, laser) lead to same change in brain activity?
• Sleep1. Determining the influence of gender and circadian cycle on
the EEG effect2. Are there functional consequences of the Sleep EEG effect?
• Cortical Excitability, and Emotional Processing1. Transcranial Magnetic Stimulation (TMS): does RF EMF
exposure lead to changes in cortical excitability?2. Are there effects of exposure to RF EMF on
emotion/emotional processing?• Effects on Cognitive Performance
1. Overcoming confounds in previous studies to determine whether RF EMF influences cognition
• Effects of Very Short and Intermittent RF EMF Exposure on Brain Activity
• IEI‐EMF Provocation Case Studies1. A novel approach to testing sensitive individuals
Other Current Research:Sleep• Sleep and Behavioural Problems in ADHD
Children1. Does mild sleep restriction lead to changes in
behaviour and performance in children?2. Do healthy children cope with mild sleep
restriction better than children with ADHD?• Sleep and Screen Time in Children
1. How does screen time, and the light emitted by these devices, affect children’s sleep?
• Sleep and Floatation1. Does floatation (Restricted Environmental
Stimulation Therapy; REST) impact sleep, brain activity or stress (cortisol)?
• First Night Effect1. How does sleep
change acrossconsecutive nights inthe laboratory?
Acknowledgements
University of Zürich
Peter Achermann
Marc Schmid
Micheline Maire
Dominik Benz
IT’IS Foundation
Niels Kuster
Manuel Murbach
Australian Centre for RadiofrequencyBioeffects Research (ACEBR)
Rodney Croft Andrew Wood
Adam Verrender Anna Dalecki
Ian Evans Sheridan Findlay
Ray McKenzie Rob McIntosh
Steve Iskra Nikolas Perentos
Other Collaborators
Alexandre Legros James Rubin
Julien Modolo Gunnhild Oftedal Rob Kavet
Giuseppe Curcio Lena Hillert Mike Silva
ETH Zürich
Robert Riener
Martin Wieser
Thank you…