Effects of microwaves emitted by cellular phones on human slow brain potentials

The influence of electromagnetic fields (EMF) emitted by cellular phones on preparatory slow brain potentials (SP) was studied in two different experimental tasks: In the first, healthy male human subjects had to perform simple self-paced finger movements to elicit a Bereitschaftspotential; in the second, they performed a complex and cognitive demanding visual monitoring task (VMT). Both tasks were performed with and without EMF exposure in counterbalanced order. Whereas subjects' performance did not differ between the EMF exposure conditions, SP parameters were influenced by EMF in the VMT: EMF exposure effected a significant decrease of SPs at central and temporo-parieto-occipital brain regions, but not at the frontal one. In the simple finger movement task, EMF did not affect the Bereitschaftspotential. Bioelectromagnetics 19:384–387, 1998. © 1998 Wiley-Liss, Inc.     

Cognitive effects of radiation emitted by cellular phones: The influence of exposure side and time

This study examined the time dependence effects of exposure to radiofrequency radiation (RFR) emitted by standard GSM cellular phones on the cognitive functions of humans. A total of 48 healthy right‐handed male subjects performed a spatial working memory task (that required either a left‐hand or a right‐hand response) while being exposed to one of two GSM phones placed at both sides of the head. The subjects were randomly divided into three groups. Each group was exposed to one of three exposure conditions: left‐side of the head, right‐side, or sham‐exposure. The experiment consisted of 12 blocks of trials. Response times (RTs) and accuracy of the responses were recorded. It was found that the average RT of the right‐hand responses under left‐side exposure condition was significantly longer than those of the right‐side and sham‐exposure groups averaged together during the first two time blocks. These results confirmed the existence of an effect of exposure on RT, as well as the fact that exposure duration (together with the responding hand and the side of exposure) may play an important role in producing detectable RFR effects on performance. Differences in these parameters might be the reason for the failure of certain studies to detect or replicate RFR effects. Bioelectromagnetics 30:198–204, 2009. © 2008 Wiley‐Liss, Inc.     

Effects of short- and long-term pulsed radiofrequency electromagnetic fields on night sleep and cognitive functions in healthy subjects

There has been wide public discussion on whether the electromagnetic fields of mobile telephones and their base stations affect human sleep or cognitive functioning. As there is evidence for learning and memory-consolidating effects of sleep and particularly of REM sleep, disturbance of sleep by radiofrequency electromagnetic fields might also impair cognitive functions. Previously realized sleep studies yielded inconsistent results regarding short-term exposure. Moreover, data are lacking on the effect that short- and long-term exposure might have on sleep as well as on cognitive functions. Therefore, 10 healthy young male subjects were included and nocturnal sleep was recorded during eight consecutive nights. In the second, third, and last night, we investigated polysomnographic night sleep and cognitive functions. After the adaptation and baseline nights, the participants were exposed to a defined radiofrequency electromagnetic field during the following six nights. We analyzed polysomnographic night sleep according to Rechtschaffen and Kales [1968, Manual of Standardized Terminology, Techniques and Scoring System for Sleep of Human Subjects] as well as by power spectra and correlation dimension. Cognitive functions were investigated by an array of neuropsychological tests. Data analysis was done by comparing the baseline night with the first and last exposure night and the first two sleep cycles of the respective nights. We did not find significant effects, either on conventional sleep parameters or on power spectra and correlation dimension, nor were there any significant effects on cognitive functions. With our results, we are unable to reveal either short-term or cumulative long-term effects of radiofrequency electromagnetic fields on night sleep and cognitive functions in healthy young male subjects.     

Effects of electromagnetic field emitted by cellular phones on the EEG during an auditory memory task: a double blind replication study

The effects of electromagnetic fields (EMF) emitted by cellular phones on the event related desynchronization/synchronization (ERD/ERS) of the 4-6, 6-8, 8-10, and 10-12 Hz electroencephalogram (EEG) frequency bands were studied in 24 normal subjects performing an auditory memory task. This study was a systematic replication of our previous work. In the present double blind study, all subjects performed the memory task both with and without exposure to a digital 902 MHz field in a counterbalanced order. We were not able to replicate the findings from our earlier study. All eight of the significant changes in our earlier study were not significant in the present double blind replication. Also, the effect of EMF on the number of incorrect answers in the memory task was inconsistent. We previously reported no significant effect of EMF exposure on the number of incorrect answers in the memory task, but a significant increase in errors was observed in the present study. We conclude that EMF effects on the EEG and on the performance on memory tasks may be variable and not easily replicable for unknown reasons.     

Effects of the microwave radiation from the cellular phones on humans and animals

Biological effects of the mobile phone microwave radiation were shown to depend on many factors: the duration of the irradiation, individual characteristics of the CNS and immune systems, and others. The cellular phone microwave radiation can induce reversible unspecific adaptive responses if it is short and the organism is very radiosensitive. A long-term exposure (over one year) combined with the organism weakened immune system may produce a cumulative effect in the form of stress responses, various damages and, in some cases, even cancer. The ultimate result of the microwave exposure depends on the balance between induced damage and the organism reparative ability.     

Influence of electromagnetic fields emitted by GSM-900 cellular telephones on the circadian patterns of gonadal, adrenal and pituitary hormones in men

The potential health risks of radiofrequency electromagnetic fields (RF EMFs) emitted by mobile phones are currently of considerable public interest. The present study investigated the effect of exposure to 900 MHz GSM radiofrequency radiation on steroid (cortisol and testosterone) and pituitary (thyroid-stimulating hormone, growth hormone, prolactin and adrenocorticotropin) hormone levels in 20 healthy male volunteers. Each subject was exposed to RF EMFs through the use of a cellular phone for 2 h/day, 5 days/ week, for 4 weeks. Blood samples were collected hourly during the night and every 3 h during the day. Four sampling sessions were performed at 15-day intervals: before the beginning of the exposure period, at the middle and the end of the exposure period, and 15 days later. Parameters evaluated included the maximum serum concentration, the time of this maximum, and the area under the curve for hormone circadian patterns. Each individual's pre-exposure hormone concentration was used as his control. All hormone concentrations remained within normal physiological ranges. The circadian profiles of prolactin, thyroid-stimulating hormone, adrenocorticotropin and testosterone were not disrupted by RF EMFs emitted by mobile phones. For growth hormone and cortisol, there were significant decreases of about 28% and 12%, respectively, in the maximum levels when comparing the 2-week (for growth hormone and cortisol) and 4-week (for growth hormone) exposure periods to the pre-exposure period, but no difference persisted in the postexposure period. Our data show that the 900 MHz EMF exposure, at least under our experimental conditions, does not appear to affect endocrine functions in men.     

The role of maternal cognitive ability on child health

Little is known about the mechanisms through which mother's cognitive ability operates in enhancing her children's health. This paper analyzes how maternal returns to cognitive ability on children's height reflect contemporaneous endowments and childhood background of the mother. Results suggest that maternal returns to cognitive ability on child height are less likely to reflect observed mother's childhood endowments as measured by parental transmission of knowledge or school quality, but are more likely to be associated with learning to be a mother, and with a better capacity to take advantage of household and community available resources.     

Effects of information and 50 Hz magnetic fields on cognitive performance and reported symptoms

The aim of this study was to explore the role of expectancies and beliefs about the potential effects of electromagnetic fields (EMFs) (what the subject thought the effect was going to be) and the effects of 50 Hz magnetic fields (400 microT(rms)) acute exposure on cognitive performance, the reporting of physical symptoms and some psychological and physiological parameters. Seventy-four healthy male volunteers aged between 40 and 60 years of age were randomly assigned to one of five groups, which differed in (1) the type of information they were given concerning the expected magnetic field effect on performance in cognitive tests (positive = enhancement of the performance; negative = impairment of the performance; neutral) and (2) the type of exposure (real or sham). Three groups were sham exposed with positive (group+), negative (group-) and neutral information (group+/-); one group was really exposed with neutral information (group expo) and one group was not exposed, though they wore the helmet, and did not receive any field-related information (control group). All the volunteers, except the control group, were led to believe that they would be exposed to a magnetic field of 400 microT(rms). The experimental design respected a double blind procedure and the experimental session involved three steps (pre-testing, exposure, and post-testing). Various measurements were taken, including cognitive performance, psychological parameters such as mood, vigilance, and reporting of symptoms. Physiological parameters such as blood pressure and pulse rate were also recorded. The information given did not significantly modify beliefs. No significant difference was found among the five groups depending on the type of information and the type of exposure in cognitive performance, psychological and physiological parameters. In the context of the study, with our population, the type of information given failed to induce expected changes in parameters measured. Our results do not support the hypothesis that an acute exposure to extremely low frequency magnetic fields (50 Hz, 400 microT(rms)) affects the parameters measured.     

Tooth loss and caries prevalence in very old Swedish people: the relationship to cognitive function and functional ability

Objective: To analyse whether cognitive function and functional ability are related to oral health among community‐dwelling older people over the age of 80 years. Background: This cross‐sectional study is based on the Kungsholmen Elders Oral Health Survey (KEOHS). The study included oral examinations carried out in two local clinics by standardised examiners and interviews using structured questionnaires. Materials and Methods: Altogether 159 individuals were included in this study. Coronal caries and root caries were assessed using the National Institute of Dental and Craniofacial Research (NIDCR) diagnostic criteria. Cognitive function was assessed by the Mini‐Mental State Examination (MMSE) index and functional ability was assessed by a global measure of self‐reported changes. Results: Older adults with a low MMSE score (≤23) tended to have a higher risk of coronal caries than those with higher scores. Participants with mild cognitive decline (MMSE = 24–26) and with a decrease in functional ability had a significantly higher risk of root caries. These associations changed little when adjusted by the covariates. In addition, people with a low MMSE (0–23) had a four times higher risk of not using dental services regularly. This result was unchanged after adjusting for the variables studied. Conclusions: This study revealed associations between the cognitive and functional status of the individual and aspects of oral health, that may contribute to a deeper understanding of the background of oral health status in older adults.     

模拟高原低氧对人的认知能力影响的研究

目的 :研究轻、中度急性缺氧暴露对人的认知能力的影响。方法 :利用低压舱模拟 30 0m(对照高度 )、2 80 0m、36 0 0m、44 0 0m低氧环境 ,考察了 18名健康男性青年受试者在不同高度暴露 1h的感知觉、记忆、注意、思维和心理运动功能的变化情况。结果 :2 80 0m暴露 1h连续识别记忆测验的综合绩效已显著低于对照水平 (P <0 .0 1) ,而36 0 0m暴露 1h后感知觉、记忆、注意、思维和心理运动等各项测验的反应时均延长 ,正确率下降 ,综合绩效显著降低 (P <0 .0 5或P <0 .0 1) ,并随着高度的增加而加重。 44 0 0m暴露 1h各项测验综合绩效进一步降低 (P <0 .0 1)。结论 :各项认知能力受低氧影响符合“高度依赖原则” ,但不同认知能力要素受低氧影响的阈限高度不同。 36 0 0m高度暴露 1h各项测验的综合绩效均显著下降 ,已无法满足工效要求。经过 1h的供氧 ,各项作业绩效基本恢复     

Effects of anesthesia-induced modest hypothermia on cellular radiation sensitivity

To assess the mechanisms of modest hypothermia (MH) and its effects on cellular radiation response, a model of anesthesia-induced modest hypothermia (AIMH) in the adult mice and a model of pure MH in the newborn mice were established. The survival rate of lethally irradiated mice was increased to 72% through AIMH before irradiation. Both apoptosis and necrosis of human fetal bone marrow CD34+ hematopoietic stem cells cultured under MH were significantly decreased as detected by MTT and flow cytometry, with three-color labeled by PE-CD34+/ FITC-AnnexinV /7AAD. The survival and proliferation of mouse bone marrow MNC treated with MH after irradiation were also increased. The MH exerted similar protective effects on the leukemia cell lines A20, HL60, K562 to the normal bone marrow cells, but it enhanced the radiation sensitivity of leukemia cell line FBL3 and mouse melanoma B16F10. No effects have been found on the radiation sensitivity of those cells treated with MH before irradiation. The results also show     

Effects of anesthesia-induced modest hypothermia on cellular radiation sensitivity

To assess the mechanisms of modest hypothermia (MH) and its effects on cellular radiation response, a model of anesthesia-induced modest hypothermia (AIMH) in the adult mice and a model of pure MH in the newborn mice were established. The survival rate of lethally irradiated mice was increased to 72% through AIMH before irradiation. Both apoptosis and necrosis of human fetal bone marrow CD34⁺ hematopoietic stem cells cultured under MH were significantly decreased as detected by MTT and flow cytometry, with three-color labeled by PE-CD₃₄ ⁺/ FITC-AnnexinV /7AAD. The survival and proliferation of mouse bone marrow MNC treated with MH after irradiation were also increased. The MH exerted similar protective effects on the leukemia cell lines A20, HL60, K562 to the normal bone marrow cells, but it enhanced the radiation sensitivity of leukemia cell line FBL3 and mouse melanoma B16F10. No effects have been found on the radiation sensitivity of those cells treated with MH before irradiation. The results also showed that MH mediated the effects on radiation sensitivity, in addition to increasing the oxygen tension. These results show different effects of MH on different cells: (i) AIMH exerts a protective effect on the normal hematopoietic stem cells, some leukemia cell lines A20, HL60, K562, and some neoplasma 3LL, LOVO. And MH exhibits a synthetic effect with anesthetic. (ii) MH enhances the radiation sensitivity of another leukemia and neoplasma cell lines FBL3, B16F10 and CT26. Therefore, AIMH has a potential to enhance the effects of radiation-therapy and decrease side effects on some tumors.     

慢性应激对不同性别小鼠空间认知能力的影响

目的:探讨慢性应激对不同性别小鼠空间认知能力的影响.方法:成年健康昆明小鼠32只,平均分为4组(n=8):雄性对照组和雄性应激组,雌性对照组和雌性应激组.研究采用改良的Kaz法,建立慢性应激小鼠模型,利用Morris水迷宫进行定位航行和空间搜索实验,观察不同性别的小鼠空间认知能力的改变.结果:经2周的应激处理后,在定位...     

Effects of combined radiofrequency radiation exposure on the cell cycle and its regulatory proteins

The aim of this study was to investigate whether single or combined radio frequency (RF) radiation exposure has effects on the cell cycle and its regulatory proteins. Exposure of MCF7 cells to either single (837 MHz) or combined (837 and 1950 MHz) RF radiation was conducted at specific absorption rate values of 4 W/kg for 1 h. During the exposure period, the chamber was made isothermal by circulating water through the cavity. After RF radiation exposure, DNA synthesis rate and cell cycle distribution were assessed. The levels of cell cycle regulatory proteins, p53, p21, cyclins, and cyclin‐dependent kinases were also examined. The positive control group was exposed to 0.5 and 4 Gy doses of ionizing radiation (IR) and showed changes in DNA synthesis and cell cycle distribution. The levels of p53, p21, cyclin A, cyclin B1, and cyclin D1 were also affected by IR exposure. In contrast to the IR‐exposed group, neither the single RF radiation‐ nor the combined RF radiation‐exposed group elicited alterations in DNA synthesis, cell cycle distribution, and levels of cell cycle regulatory proteins. These results indicate that neither single nor combined RF radiation affect cell cycle progression. Bioelectromagnetics 32:169–178, 2011. © 2010 Wiley‐Liss, Inc.     

Effects of cognitive challenge on self-directed behaviors by chimpanzees (Pan troglodytes)

In primates, including humans, scratching and other self-directed behaviors (SDBs) have recently been reported to be differentially displayed as a function of social interactions, anxiety-related drugs, and response outcomes during learning tasks. Yet few studies have focused on the factors influencing SDBs in our closest living relatives, the chimpanzees (Pan troglodytes). Furthermore, no previous experimental study has examined handedness of SDBs as a function of changes in task difficulty. Using matching-to-sample tasks of varying difficulty, the present study examines the effect of manipulations of task difficulty on rates, handedness, and type of SDBs in an experimental study of eight chimpanzees. SDBs were categorized as rubs, gentle scratches, and rough scratches. SDBs increased during difficult discriminations, but only for subjects who started the experiment on an easy discrimination; subjects who started on a difficult discrimination exhibited no differential rates of SDBs as a function of task difficulty. There was a tendency to exhibit relatively more SDBs with the right hand in the more difficult task. Rates of SDBs decreased after auditory feedback signals, suggesting a link between SDBs and uncertainty. Rubs were directed more to the face (trigeminal), and gentle and rough scratches more to the body (spinothalamic), suggesting that face-directed SDBs may index a different motivational basis than scratches. Taken together, these results extend previous research on SDBs to the domain of cognitive stress in nonsocial contexts, demonstrating that SDBs are sensitive to manipulations of task difficulty in chimpanzees.     

Effects of exposure to electromagnetic fields emitted by GSM 900 and WCDMA mobile phones on cognitive function in young male subjects

Results of studies on the possible effects of electromagnetic fields emitted by mobile phones on cognitive functions are contradictory, therefore, possible effects of long‐term (7 h 15 min) electromagnetic field (EMF) exposure to handset‐like signals of Global System for Mobile Communications (GSM) 900 and Wideband Code‐Division Multiple Access (WCDMA) on attention and working memory were studied. The sample comprised 30 healthy male subjects (mean ± SD: 25.3 ± 2.6 years), who were tested on nine study days in which they were exposed to three exposure conditions (sham, GSM 900 and WCDMA) in a randomly assigned and balanced order. All tests were presented twice (morning and afternoon) on each study day within a fixed timeframe. Univariate comparisons revealed significant changes when subjects were exposed to GSM 900 compared to sham, only in the vigilance test. In the WCDMA exposure condition, one parameter in the vigilance and one in the test on divided attention were altered compared to sham. Performance in the selective attention test and the n‐back task was not affected by GSM 900 or WCDMA exposure. Time‐of‐day effects were evident for the tests on divided and selective attention, as well as for working memory. After correction for multiple testing, only time‐of‐day effects remained significant in two tests, resulting in faster reactions in the afternoon trials. The results of the present study do not provide any evidence of an EMF effect on human cognition, but they underline the necessity to control for time of day. Bioelectromagnetics 32:179–190, 2011. © 2010 Wiley‐Liss, Inc.     

Effects of the LHRH antagonist Cetrorelix on affective and cognitive functions in rats

The decapeptide LHRH antagonist, Cetrorelix, inhibits gonadotropin and sex-steroid secretion. Cetrorelix is used for IVF-ET procedures and for the treatment of benign prostatic hyperplasia, endometriosis and leiomyomas. However little is known about the effects of Cetrorelix on brain functions. Previously we have tested Cetrorelix in mice on the impairment of the consolidation of a passive avoidance behavior caused by beta-amyloid 25–35, anxiolytic action in the plus-maze, antidepressive action in a forced swimming test, tail suspension and open-field behavior following its administration into the lateral brain ventricle. In the present study we repeated and extended the experiments in rats in order to determine whether there are species differences in the action of Cetrorelix between mice and rats. The effects of Cetrorelix evaluated included the methods used in mice without tail suspension test and extended by measuring core temperature. Cetrorelix fully blocked the impairment of the consolidation of passive avoidance learning when given icv 30 min following administration of beta-amyloid 25–35. If beta-amyloid 25–35 and Cetrorelix were given simultaneously, Cetrorelix was ineffective. Cetrorelix elicited slight anxiogenic and stronger anxiolytic action in the plus-maze, depending on the dose used. In the forced swimming tests, Cetrorelix showed antidepressive-like action. In open-field behavior tests Cetrorelix displayed a U-type action on locomotion with 0.5 and 2 µg increasing locomotion, and increase rearing but and had no effect on grooming at 0.5–2 µg. Cetrorelix had no action on core temperature. Our findings demonstrate that Cetrorelix is able to correct the impairment of the memory consolidation caused by beta-amyloid 25–35. Cetrorelix elicits anxiolytic and antidepressive action, slightly increases locomotion and rearing in open field, but it does not influence the core temperature. The results obtained in rats are similar to those reported previously by us in mice. Collectively our findings confirm the effects of Cetrorelix on brain function in two species and suggest the possible merit of a clinical trial with Cetrorelix in patients with anxiety, depression and Alzheimer's disease.