Electromagnetic fields (EMFs) generated by the use of 5G technology influence certain sleep characteristics, especially in individuals carrying a specific genetic variant of a protein in the brain that regulates the activity of nerve cells. This protein is a voltage-gated calcium channel called CaV1.2 and could be involved in the effects of 5G technology on sleep. The calcium channel CaV1.2 can be selectively blocked by the drug nimodipine. To demonstrate that CaV1.2 is indeed involved in the effects of 5G technology on sleep, the researchers are investigating in this study, with healthy subjects carrying the sought-after genetic variant, whether the administration of nimodipine and thus the blockade of the calcium channel before exposure mitigates or eliminates the effects of EMF on sleep health.
This study tests a causal role of voltage-gated CaV1.2 calcium channels in mediating the effects of a 5G electromagnetic field on sleep-related brain health in humans. The study comprises a large-scale genetic screening in order to select the allele-carriers, a sleep screening night, and four experimental nights where participants are exposed to either an active 5G field or sham, combined with either nimodipine (which is a brain-penetrant L-type calcium channel blocker) or placebo. Participants will undergo polysomnographic recordings, high-density electroencephalography (EEG) during wake, peripheral measurements, cognitive and neuropsychiatric assessments.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
30
Two times 30 mg nimodipine or placebo will be administered orally 45 minutes prior to the start of the 5G FR1 exposure. The verum and placebo capsules will look the same, in order to preserve the double-blinding.
Participants will be exposed to a standardized electromagnetic field of the latest mobile radio standard (5G) or a sham field for 30 minutes on each of the experimental nights. The active field is characterized by 3.6 GHz frequency \[TDD\] with 100 MHz bandwidth, 12-14 Hz modulation and is comparable to a phone call with a commercially available, modern cell phone. Both the 5G and sham exposures are performed with the same exposure apparatus, according to a double-blind study design.
University of Zurich, Institute of Pharmacology and Toxicology
Zurich, Canton of Zurich, Switzerland
RECRUITINGSleep spindle center frequency
In previous research, the investigators detected a positive shift in the sleep spindle center frequency (during NREM sleep phase) after 30-min pre-sleep exposure to a 5G signal at 3600 MHz, 100 MHz bandwidth in heterozygous T/C allele-carriers (rs7304986) compared to sham. The sleep spindle center frequency is a parameter that can be extracted from the overnight electroencephalographic recordings.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Sex distribution of participants
Self-reported biological sex (male or female) is recorded during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Age of Participants
Age is recorded in years based on the year of birth provided during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Pregnancy status
Female participants report current pregnancy status during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
EEG power spectra during Non-Rapid-Eye-Movement (NREM) sleep
Power spectra will be computed from artifact-free EEG data recorded during NREM sleep. Spectral power (µV²/Hz) will be computed in standard frequency bands.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Total sleep time
Sleep electroencephalographic data allow to extract total sleep time (min) (total amount of time spent asleep)
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Neurocognitive performance as assessed in the psychomotor vigilance task (PVT)
The PVT is administered before and after sleep at each experimental night and provides a score reflecting sustained or vigilant attention performance.
Time frame: Assessed on each of the four experimental nights, pre- and post-sleep
Heart rate
Heart rate (bpm) is extracted from electrocardiographic recording during exposure and from polysomnographic overnight recordings
Time frame: Assessed on each of the four experimental nights, from electrocardiographic recordings during pre-sleep exposure and polysomnographic overnight recordings
Handedness of participants
Participants report their handedness (right-handed or left-handed) during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
BMI of participants
Self-reported height (in centimeters) and weight (in kilograms) of participants is reported during the large-scale genetic screening (first study part) via an online questionnaire. From Height and Weight, BMI is calculated.
Time frame: At the large-scale genetic screening
Highest level of education of participants
The highest level of education of participants (elementary school, professional school, high school, university of applied sciences and arts, or university) is self-reported during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Phone call time
Participants report their phone call time without headphones (Not at all, Less than 1 hour per week, 1-2 hours per week or more than 2 hours per week) during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Caffeine consumption
Participants report their caffeine consumption (None, 1-2 caffeinated foods or beverages per day, 3-5 caffeinated foods or beverages per day or More than 5 caffeinated foods or beverages per day) during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Alcohol consumption
Participants report their alcohol consumption (None, Less than 1 glass per week, 1-2 glasses per week, 3-5 glasses per week or More than 5 glasses per week) during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Electrohypersensitivity (EHS) status
Participants report their EHS status during the large-scale genetic screening (first study part) via filling out the online questionnaire by M. Röösli, E. Mohler, and P. Frei (2010).
Time frame: At the large-scale genetic screening
Sleep disturbances
The presence of sleep disturbances is self-reported by participants during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Comorbidities
Participants self-report the presence of comorbidities during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Night-shift work
Participants report if they engage in night shift work during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Use of medications
Self-reported use of medication is recorded during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Use of illegal drugs
Self-reported use of illegal drugs is recorded during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Use of tobacco products
Use of tobacco products is reported during the large-scale genetic screening (first study part) via an online questionnaire.
Time frame: At the large-scale genetic screening
Subjective sleep quality
Participants report about their subjective sleep quality during the large-scale genetic screening (first study part) via filling out the online questionnaire "Pittsburgh Sleep Quality Index" (high global PSQI score indicates poor sleep quality).
Time frame: At the large-scale genetic screening
Daytime sleepiness
Participants report about their daytime sleepiness during the large-scale genetic screening (first study part) via filling out the online questionnaire "Epworth Sleepiness Scale " (high ESS score indicates high daytime sleepiness).
Time frame: At the large-scale genetic screening
Diurnal preference
Participants report about their diurnal preference during the large-scale genetic screening (first study part) via filling out the online questionnaire "Munich Chronotype Questionnaire" (if the mid-sleep time on the MCTQ is earlier than 04:00, the participant is considered as preferential morning type, otherwise as preferential evening type).
Time frame: At the large-scale genetic screening
Habitual bedtime
Participants report about their subjective habitual bedtime (hh:mm) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Pittsburgh Sleep Quality Index".
Time frame: At the large-scale genetic screening
Habitual rise time
Participants report about their subjective habitual rise time (hh:mm) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Pittsburgh Sleep Quality Index".
Time frame: At the large-scale genetic screening
Reported time to fall asleep
Participants report about their subjective time to fall asleep (min) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Pittsburgh Sleep Quality Index".
Time frame: At the large-scale genetic screening
Reported sleep duration
Participants report about their subjective sleep duration (h:mm) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Pittsburgh Sleep Quality Index".
Time frame: At the large-scale genetic screening
Positive and Negative Affect Schedule
Participants report about positive and negative feelings (over the last 12 months) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Positive and Negative Affect Schedule".
Time frame: At the large-scale genetic screening
Nocturnal mentation
Participants report about their nocturnal mentation during the large-scale genetic screening (first study part) via filling out online the "Dream Thought Questionnaire".
Time frame: At the large-scale genetic screening
Depressive tendency
Participants report about their depressive-like symptoms (experienced in the last 2 weeks) during the large-scale genetic screening (first study part) via filling out the online questionnaire "Beck Depression Index II (BDI-II)".
Time frame: At the large-scale genetic screening
Mental suggestibility tendency
Participants report about their mental suggestibility tendency during the large-scale genetic screening (first study part) via filling out the online questionnaire "Short Suggestibility Scale".
Time frame: At the large-scale genetic screening
Schizotypal tendency
Participants report about their schizotypal tendencies during the large-scale genetic screening (first study part) via filling out an online adaptation of the questionnaire "Magical Ideation Scale (MIS)".
Time frame: At the large-scale genetic screening
ADHD tendency
Participants report about their ADHD-like symptoms during the large-scale genetic screening (first study part) via filling out the online questionnaire "Adult ADHD Self-Report Scale v1.1 (ASRS)".
Time frame: At the large-scale genetic screening
EEG power spectra during wakefulness
Power spectra will be computed from artifact-free EEG data recorded during wakefulness. Spectral power (µV²/Hz) will be computed in standard frequency bands.
Time frame: Assessed on each of the four experimental nights, from pre- and post-sleep wake electroencephalographic recordings
EEG power spectra during Rapid Eye Movement (REM) sleep
Power spectra will be computed from artifact-free EEG data recorded during REM sleep. Spectral power (µV²/Hz) will be computed in standard frequency bands.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Aperiodic component of the EEG power spectrum during NREM sleep
The NREM sleep power spectra will be used to extract and parametrize the aperiodic component.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Aperiodic component of the EEG power spectrum during REM sleep
The REM sleep power spectra will be used to extract and parametrize the aperiodic component.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Aperiodic component of the EEG power spectrum during wakefulness
The wake power spectra will be used to extract and parametrize the aperiodic component.
Time frame: Assessed on each of the four experimental nights, from pre- and post-sleep wake electroencephalographic recordings
Periodic component of the EEG power spectrum during NREM sleep
Gaussian peaks detected in the NREM sleep power spectrum will be used to extract the periodic components, including center frequency, power, and bandwidth.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Periodic component of the EEG power spectrum during REM sleep
Gaussian peaks detected in the REM sleep power spectrum will be used to extract the periodic components, including center frequency, power, and bandwidth.
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions.
Periodic component of the EEG power spectrum during wakefulness
Gaussian peaks detected in the wake power spectrum will be used to extract the periodic components, including center frequency, power, and bandwidth.
Time frame: Assessed on each of the four experimental nights, from pre- and post-sleep wake electroencephalographic recordings
Sleep efficiency
Sleep electroencephalographic data allow to extract sleep efficiency (%) ((total sleep time/time in bed) \* 100)
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Sleep latency
Sleep electroencephalographic data allow to extract sleep latency (time between lights-off and first occurrence of NREM sleep stage N2).
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions.
Wakefulness after sleep onset
Sleep electroencephalographic data allow to extract WASO (min) (wakefulness after sleep onset).
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Time spent in the different sleep stages
Sleep electroencelographic data allow to calculate the time (min) spent in each sleep substage (NREM1, NREM2, NREM3, REM).
Time frame: Assessed on each of the four experimental nights, from overnight electroencephalographic recordings following randomized combinations of drug (nimodipine or placebo) and RF-EMF exposure (5G or sham), with a minimum of 3 days washout between sessions
Neurocognitive performance as assessed in the sequential finger tapping task (FTT)
The FTT is administered before and after sleep at each experimental night and provides a score reflecting procedural memory and learning performance.
Time frame: Assessed on each of the four experimental nights, pre- and post-sleep
Neurocognitive performance as assessed in the visuospatial 2D Object Location Task (OLT)
The OLT is administered before and after sleep at each experimental night and provides a score reflecting declarative memory and learning performance.
Time frame: Assessed on each of the four experimental nights, pre- and post-sleep
Heart rate variability
Heart rate variability is extracted from electrocardiographic recording during exposure and from polysomnographic overnight recordings.
Time frame: Assessed on each of the four experimental nights, from electrocardiographic recordings during pre-sleep exposure and polysomnographic overnight recordings
Pupil size
Pupil size variation is recorded during exposure.
Time frame: Assessed on each of the four experimental nights, from pupillometry recordings during pre-sleep exposure.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.