Browse 6,486 peer-reviewed studies on electromagnetic field health effects from 4 research libraries.
Showing 2,030 studies in Brain & Nervous System
Mahdavi SM, Sahraei H, Yaghmaei P, Tavakoli H. · 2014
Researchers studied the effects of extremely low frequency electromagnetic field (ELF-EMF) exposure at 1 and 5 Hz on behavioral, hormonal, and metabolic changes in male Wistar rats. Plasma ACTH concentration increased in both frequency groups, while noradrenaline concentration showed an overall reduction.
Li Y, Yan X, Liu J, Li L, Hu X, Sun H, Tian J. · 2014
Researchers examined the effects of pulsed electromagnetic field (PEMF) exposure on brain-derived neurotrophic factor (BDNF) gene expression in cultured dorsal root ganglion neurons from neonatal rats. Exposure to 50 Hz and 1 mT PEMF for 2 hours increased both intracellular free calcium levels and Bdnf mRNA expression. The increase in calcium was found to come from influx through L-type voltage-gated calcium channels, while calcium mobilization from internal stores was not involved. Blocking the Erk signaling pathway strongly inhibited PEMF-related Erk1/2 activation and BDNF expression, indicating that Erk activation was required for PEMF-induced BDNF upregulation.
Li C, Xie M, Luo F, He C, Wang J, Tan G, Hu Z. · 2014
Researchers investigated the effects of 14 and 28 days of exposure to a 50 Hz, 0.5 mT extremely low-frequency magnetic field on glutamate receptor subunit expressions and spatial learning and memory in rats. The exposure changed NMDAR and AMPAR subunit levels in the hippocampus, entorhinal cortex, and prefrontal cortex in ways that differed by brain region and duration. Despite these receptor changes, neither 14 nor 28 days of exposure affected the rats' spatial reference memory as assessed by water maze.
Komaki A, Khalili A, Salehi I, Shahidi S, Sarihi A. · 2014
Researchers divided twenty-nine adult male Wistar rats into three groups: an ELF-EMF exposed group, a sham group, and a control group. The exposed rats received a 50 Hz, 100 micro Tesla magnetic field for 90 consecutive days at 2 hours per day. Prolonged exposure to ELF-EMFs increased LTP induction, and there was a significant difference in the slope of EPSP and amplitude of PS between the ELF-EMF group and other groups. The researchers' data suggest that exposure to ELF-EMFs produces a marked change in the synaptic plasticity generated in synapses of the PP-DG.
Kantar Gok D et al. · 2014
Researchers used ninety male rats, aged 3 months, to investigate how different intensities and durations of extremely low-frequency electric fields affected brain responses and oxidative damage. Rats were exposed to 12-kV/m and 18-kV/m electric fields for 2 or 4 weeks, and mismatch negativity (MMN) responses were recorded in anesthetized rats using electrodes placed on the dura. MMN amplitude was significantly decreased in the E18-4 group compared with the C4 group, and 4-HNE was increased in all experimental groups compared with the control group. The researchers concluded that the electric field decreased MMN amplitudes, possibly induced by lipid peroxidation.
Hernádi L, László JF. · 2014
Researchers studied how a single, 30-minute, whole-body static magnetic field exposure at 147±3 mT affected pain response latency in the snail Helix pomatia, using the hot plate test. Compared to sham-exposure, the static magnetic field caused significant differences in response latency of up to 47.1% (p < 0.001). The study concluded that static magnetic field exposure mediates peripheral thermal nociceptive threshold by affecting the serotonin as well as the opioid system.
Giorgi G et al. · 2014
Researchers investigated whether pulsed magnetic field exposure could interfere with DNA damage and repair in human neuroblastoma BE(2)C cells under oxidative stress. Cells were treated with hydrogen peroxide and exposed to a pulsed magnetic field at 1 mT and 50 Hz, and DNA double strand breaks were tracked using gamma-H2AX foci formation at 1, 24, 48, and 72 hours after treatment. The results suggest that pulsed magnetic field exposure does not interfere with genotoxicity and cytotoxicity induced by oxidative stress.
Duan Y, Wang Z, Zhang H, He Y, Fan R, Cheng Y, Sun G, Sun X. · 2014
Researchers studied whether exposure to a 50 Hz, 8 mT extremely low frequency electromagnetic field for 28 days altered glutamate release in mice hippocampus and whether treatment with lotus seedpod procyanidins (LSPCs) could normalize those changes. Exposure increased glutamate, GABA, NMDA receptor 2B levels, and intracellular calcium concentration in the hippocampus, while decreasing ERK1/2 and CREB phosphorylation. Oral administration of LSPCs, especially at 60 and 90 mg per kilogram, markedly improved expressions of p-CREB, p-ERK1/2, and p-JNK1/2, and was accompanied by decreased levels of glutamate, GABA, intracellular calcium, and NR2B.
Dimitrijević D, Savić T, Anđelković M, Prolić Z, Janać B. · 2014
Researchers exposed Drosophila subobscura at different developmental stages to an extremely low frequency magnetic field (50 Hz, 0.5 mT) for 48 hours. The magnetic field shortened developmental time and increased viability, while sex ratio was unaffected. Regardless of which developmental stage was exposed, the magnetic field significantly decreased locomotor activity in adult flies. When just-eclosed adults were exposed, the observed reduction in locomotor activity lasted longer than in other exposure groups.
Alsaeed I et al. · 2014
Researchers examined the effects of perinatal exposure to ELF EMF on autism-relevant behavioral parameters in male BALB/C mice. Exposed mice lacked normal sociability and preference for social novelty, and also showed decreased exploratory activity. The researchers concluded that the results are supportive of the hypothesis of a causal link between exposure to ELF EMF and ASD, but recommended replications with further tests.
Yilmaz A et al. · 2014
Researchers exposed rats to electromagnetic waves from mobile phones at frequencies between 1900 and 2100 MHz for a four-week period to study effects on apoptosis-related proteins in brain tissue. Immunohistopathological examinations showed that the study group had more p53 and Bcl-2 positive stained cells, and they were stained denser, with statistically significant differences between the study and control groups (p < 0.003). The researchers concluded that electromagnetic waves from mobile phones may have an effect on apoptosis.
Wang H et al. · 2014
Eighty Wistar rats were exposed to a 2.856 GHz pulsed microwave source at power densities of 0 mW/cm2 and 50 mW/cm2 for 6 minutes, and then observed at multiple time points up to 18 months after exposure. The microwave-exposed rats showed consistent deficiencies in spatial learning and memory. The level of amino acid neurotransmitters decreased after microwave radiation, and the ratio of glutamate and gamma-aminobutyric acid significantly decreased at 6 months. The hippocampus showed varying degrees of degeneration of neurons, and NR1 and NR2B expression showed a significant decrease, especially NR2B expression.
Schneider J, Stangassinger M · 2014
Researchers exposed male and female rats continuously to either 900-MHz GSM or 1.966-GHz UMTS electromagnetic fields at 0.4 W/kg. Memory was assessed using a social discrimination procedure, with differences in sniffing duration to familiar and novel juvenile rats used as the measure. EMF-exposed females showed no differences in sniffing duration compared with controls, but sniffing durations of EMF-exposed males at 3 months of age were significantly affected. At 6 months of age, GSM-exposed male adults showed a memory performance deficit, but UMTS-exposed males did not.
Razavinasab M, Moazzami K, Shabani M · 2014
Researchers exposed pregnant Wistar rats to 900 MHz pulsed-EMF irradiation for 6 hours per day during gestation, then tested the offspring using behavioral, histological, and electrophysiological methods. Mobile phone exposure was associated with a decrease in the number of action potentials fired and an increase in the amplitude of afterhyperpolarization in exposed offspring compared with controls. Phone exposure significantly altered learning acquisition and memory retention in both male and female offspring rats compared with control rats. Light microscopy of brain sections showed normal morphology in both control and mobile phone-exposed rats.
Qin F, Yuan H, Nie J, Cao Y, Tong J · 2014
Researchers exposed male mice to 1800 MHz radiofrequency fields at 208 microW/cm2 for 0, 30, or 120 minutes per day for 30 days, while some groups also received nano-selenium by intra-gastric injection. Significant impairments in learning and memory were observed in the RF 120 min group, along with reduced acetylcholine levels and antioxidant enzyme activity and increased GABA, glutamate, and MDA in the brain. Nano-selenium supplementation decreased GABA, glutamate, and MDA levels and increased acetylcholine levels and antioxidant enzyme activities in the exposed mice.
Qiao S et al. · 2014
Researchers exposed Wistar rats, rat hippocampal synaptosomes, and PC12 cells to microwave radiation for 5 minutes at a mean power density of 30 mW/cm2. Spatial learning and memory in rats was assessed using the Morris Water Maze navigation task, and there was a decrease in spatial memory performance after microwave exposure. The expression of phosphorylated synapsin I (ser-553) was decreased at 3 days post-exposure and elevated at later time points, while GABA release from synaptosomes was attenuated. Both microwave exposure and synapsin I silencing reduced GABA release, and the greatest reduction was found when both were combined, indicating a synergetic effect.
Pelletier A et al. · 2014
Researchers recorded thermal preference and sleep in 18 young male Wistar rats, with nine exposed to a low-intensity RF-EMF at 900 MHz and nine serving as non-exposed controls. During the light period, exposed rats preferred to sleep at an air temperature of 31°C while controls preferred 28°C. During the dark period, no significant differences between groups were found.
Narayanan SN, Kumar RS, Kedage V, Nalini K, Nayak S, Bhat PG · 2014
Researchers studied the effects of 900 MHz radio-frequency electromagnetic radiation on oxidant stress and antioxidant defense in discrete brain regions of adolescent rats. Thirty-six male Wistar rats aged 6 to 8 weeks were divided into a control group, a sham group, and an RF-EMR-exposed group, with 12 animals in each group. The exposed group received 900 MHz RF-EMR at a peak power density of 146.60 µW/cm2 for one hour per day for four weeks from an activated GSM mobile phone. Elevated TBARS levels were found in all brain regions studied, and altered behavioral performances were found in RF-EMR-exposed rats.
Motawi TK, Darwish HA, Moustafa YM, Labib MM. · 2014
Maskey D, Kim MJ · 2014
Researchers applied radiofrequency at a specific absorption rate of 1.6 W/kg or 0 W/kg to mice to study the distribution of BDNF and GDNF in the nuclei of the superior olivary complex. In the exposed group, significant reductions in BDNF immunoreactivity were noted in the lateral superior olive, medial superior olive, superior paraolivary nucleus, and medial nucleus of the trapezoid body. GDNF immunoreactivity was also significantly decreased (p < 0.001) in all superior olivary complex nuclei of the exposed group. The researchers suggested that the decrease in these neurotrophic factors in the superior olivary complex suggests a detrimental effect of RF exposure in the auditory nuclei.
Lu Y et al. · 2014
Researchers exposed microglial N9 and astroglial C8-D1A cells to 1800 MHz radiofrequency fields to study pro-inflammatory responses and the mechanisms involved. Radiofrequency exposure induced different expression and release profiles of inflammatory markers including IL-1β, TNF-α, IL-6, PGE2, nitric oxide, inducible nitric oxide synthase, and cyclooxygenase 2 in the two cell types. STAT3 was activated by radiofrequency exposure in microglia but not in astrocytes, and the STAT3 inhibitor Stattic reduced the release of pro-inflammatory cytokines in microglia but not in astrocytes.
Li H et al. · 2014
Researchers exposed Wistar rats to 2.856 GHz microwaves at power densities of 5, 10, 20, or 30 mW/cm2 for 6 minutes three times a week for up to 6 weeks. Spatial learning and memory, hippocampus structure, brain electrical activity, and neurotransmitter levels were assessed at different time points after the last exposure. The study found dose-dependent memory deficits alongside inhibition of brain electrical activity, hippocampus neuron degeneration, and neurotransmitter disturbances. The researchers suggested that the serotonin system may be involved in the cognitive deficits seen after long-term microwave exposure.
Lee W, Yang KL · 2014
Researchers used medaka fish embryos (Oryzias latipes) to study how electromagnetic fields affect development and behavior. Newly fertilized embryos were randomly assigned to groups exposed to an EMF at 3.2 kHz at intensities of 0.12, 15, 25, or 60 µT, with the 0.12 µT group serving as the control. Embryos exposed to all three EMF levels developed significantly faster across several endpoints, including somite number, eye dimensions, eye pigmentation density, midbrain width, head growth, and day to hatch. The group exposed to 60 µT showed significantly higher levels of anxiety-like behavior than the other groups.
Júnior LC et al. · 2014
Researchers exposed male Wistar rats to radiofrequency electromagnetic radiation from a GSM cell phone (1·8 GHz) for 3 days. After exposure, behavioral tests including the open field and object recognition tests were performed. The exposed animals did not present anxiety patterns or working memory impairment, but stress behavior actions were observed.
Jung IS, Kim HJ, Noh R, Kim SC, Kim CW. · 2014
Researchers investigated how extremely low frequency magnetic fields affect nerve-growth-factor-induced neuronal differentiation of PC12 cells using proteomic methods. After 5 days of exposure at 50 Hz and 1 mT, neurite length and the number of neurite-bearing cells increased, while proliferation activity decreased. Six proteins were found to be differentially expressed between exposed and unexposed NGF-treated cells, including peripherin, VGF8a, HSP72-psI, LMW-PTP/ACP1, TUBA1A, and OPA1L.