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2.
Biol Futur ; 75(1): 61-71, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38386191

ABSTRACT

Functional visceral problems are frequently present nowadays in the medical practice probably due to the significant mental and emotional load on people. Although physicians and psychophysiologists are active on the field, still we are far from a complete knowledge, despite the fact that scientists like the Hungarian Professor György Ádám already had initiated a new approach called visceral psychophysiology already a long time ago. In this article, we commemorate Professor Ádám by analyzing one of the most frequent functional disorders, irritable bowel syndrome (IBS), calling psychophysiology for help. First, we try to give a definition, then show the general descriptions and characteristics of IBS. Factors like stress, gender, and gastrointestinal pain are followed by the potential role of the immune system and the neuronal factors as well as the supposed brain mechanisms. We hope that this overview of the IBS-history would show how significant scientists can be decisive in certain fields of the science and practice.


Subject(s)
Irritable Bowel Syndrome , Humans , History, 20th Century , History, 21st Century , Irritable Bowel Syndrome/history , Irritable Bowel Syndrome/physiopathology , Irritable Bowel Syndrome/psychology , Gastroenterology/history
3.
Heliyon ; 8(10): e10903, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36212016

ABSTRACT

This qualitative study deals with the military service of people who have lost their job due to the Covid-19 pandemic. In addition to its basic tasks, the Hungarian Defence Forces has been the first to get involved in the Hungarian Government's Economy Protection Action Plan by creating jobs for unemployed citizens. The study was conducted among those who had signed up for the temporarily created special volunteer reservist service aiming to find out what motivated them to choose the military career and what their future ambitions are. After the Grounded Theory analysis of 49 semi-structured interviews, it was found that the special volunteer service provides livelihood and daily routines for those involved but still they have very few plans for the future.

4.
Curr Psychol ; : 1-11, 2022 Feb 11.
Article in English | MEDLINE | ID: mdl-35194358

ABSTRACT

Covid-19 pandemic has changed availability of reasonable jobs. To avoid joblessness, many young adults selected military service in Hungary. The aim of this research was to study their motivation, their individual needs and the way they think about the military forces. In this study, half-structured, focus group interviews with standard questions have been qualitatively analyzed by applying the Grounded Theory (GT) method. Three levels of coding were applied: open (basic), axial and selective coding. This process resulted in fewer codes representing larger categories leading to a final concentrated overview of the interviews. Three selective codes (Enrollment, Pathfinding, Fulfillment), and many sub-codes were identified. We could establish that the effect of the Covid-19 pandemic for the military career-choice really can be detected in many individuals. The military force offers for them safe, predictable existence and career image, in which, in addition to continuous learning and development, teamwork and camaraderie provides major motivations.

5.
Int J Behav Med ; 23(3): 327-332, 2016 06.
Article in English | MEDLINE | ID: mdl-26780634

ABSTRACT

PURPOSE: Side effects consist of drug-specific and non-specific symptoms. Both components are based on bodily sensations that a person perceives after taking a drug and subsequently attributes to the drug. We suggest that somatosensory amplification (SSA) may explain a proportion of inter-individual differences in reports of side effects that cannot be accounted for by drug-specific safety profiles. This hypothesis was investigated in hypertensive patients starting a new pharmacotherapy. METHOD: This longitudinal study included 50 patients (66 % women, aged 55 ± 14 years) with a diagnosis of primary hypertension. Patients completed the Somatosensory Amplification Scale (SSAS), started to take their new medication, and recorded side effects on a daily basis for 4 weeks. RESULTS: After controlling for age, gender, number of pills taken, and previous personal and family experiences with medication side effects in the regression analyses, SSAS scores remained a significant predictor of reported side effects over the entire study period (weeks 1 and 2: ß = .621, p < .001; weeks 3 and 4: ß = .493, p = .003). In a subsample comprising patients taking the four most commonly used drug regimes, SSAS was a significant predictor of side effects, even when controlling for type of medication. CONCLUSION: In this sample of patients undergoing anti-hypertensive pharmacotherapy, higher SSA scores predicted increased reports of medication side effects. To account for this tendency and to improve compliance with medication regimes, this group may require special education about the nocebo phenomenon.


Subject(s)
Antihypertensive Agents/adverse effects , Hypertension/drug therapy , Sensation/drug effects , Adult , Aged , Antihypertensive Agents/administration & dosage , Female , Humans , Longitudinal Studies , Male , Middle Aged , Pilot Projects , Regression Analysis , Self Report
6.
Biol Psychol ; 109: 111-9, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25976524

ABSTRACT

Salivary alpha-amylase (sAA) is used as a sympathetic (SNS) stress marker, though its release is likely co-determined by SNS and parasympathetic (PNS) activation. The SNS and PNS show asynchronous changes during acute stressors, and sAA responses may thus vary with sample timing. Thirty-four participants underwent an eight-minute memory task (MT) and cold pressor task (CPT). Cardiovascular SNS (pre-ejection period, blood pressure) and PNS (heart rate variability) activity were monitored continuously. Unstimulated saliva was collected repeatedly during and after each laboratory stressor, and sAA concentration (U/ml) and secretion (U/minute) determined. Both stressors increased anxiety. The MT caused an immediate and continued cardiac SNS activation, but sAA concentration increased at task cessation only (+54%); i.e., when there was SNS-PNS co-activation. During the MT sAA secretion even decreased (-35%) in conjunction with flow rate and vagal tone. The CPT robustly increased blood pressure but not sAA. In summary, sAA fluctuations did not parallel changes in cardiac SNS activity or anxiety. sAA responses seem contingent on sample timing and flow rate, likely involving both SNS and PNS influences. Verification using other stressors and contexts seems warranted.


Subject(s)
Parasympathetic Nervous System/physiology , Saliva/metabolism , Salivary alpha-Amylases/metabolism , Stress, Psychological/metabolism , Stress, Psychological/physiopathology , Sympathetic Nervous System/physiology , Adult , Blood Pressure/physiology , Female , Heart Rate/physiology , Humans , Male , Saliva/chemistry , Young Adult
7.
Eur J Sport Sci ; 15(4): 315-21, 2015.
Article in English | MEDLINE | ID: mdl-25189187

ABSTRACT

While an increasing number of research is devoted to the understanding of placebo effects in sports, athletes' experiences with and attitudes towards the use of placebo for performance enhancement remain poorly understood. In this study, 79 elite athletes from different sports were surveyed on five issues related to placebo use in sports. Results showed that 47% of the athletes have experienced placebo effects in the past. A majority of the athletes (82%) thought that placebos could affect their sports performances. A wider use of placebos in sport settings was endorsed more by those who have experienced placebo effects in the past than those who did not (P = .005). Regardless of past experience with placebo, more than half of the athletes (53%) would accept an unknown but legitimate substance from the coach, and 67% of them would not mind a placebo-linked deception if that was effective. These findings confirm that most elite athletes believe in the power of placebos in enhancing sports performance, and those having a positive past experience exhibit slightly more favourable attitudes in contrast to those without such experiences.


Subject(s)
Athletes/psychology , Health Knowledge, Attitudes, Practice , Performance-Enhancing Substances/administration & dosage , Placebo Effect , Placebos/administration & dosage , Adolescent , Adult , Athletic Performance , Competitive Behavior , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
8.
J Health Psychol ; 20(12): 1549-57, 2015 Dec.
Article in English | MEDLINE | ID: mdl-24406331

ABSTRACT

In the development of somatosensory amplification, health anxiety, and modern health worries, environmental factors seem more important than genetic background. Parental attitudes might represent a major source of learning. In total, 186 adolescents and their parents completed a questionnaire assessing modern health worries, somatosensory amplification, health anxiety, and somatic symptoms. Adolescents' modern health worries, somatosensory amplification, and health anxiety were positively related to respective parental characteristics in regression analyses even after controlling for sociodemographic variables and somatic symptoms. Parental beliefs may play a role in the development of these characteristics.


Subject(s)
Adolescent Behavior/psychology , Anxiety Disorders/psychology , Health Knowledge, Attitudes, Practice , Hypochondriasis/psychology , Parents/psychology , Adolescent , Adult , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
9.
Int J Dev Neurosci ; 31(8): 724-30, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24012627

ABSTRACT

An earlier study demonstrated changes in synaptic efficacy and seizure susceptibility in adult rat brain slices following extremely low-frequency magnetic field (ELF-MF) exposure. The developing embryonic and early postnatal brain may be even more sensitive to MF exposure. The aim of the present study was to determine the effects of a long-term ELF-MF (0.5 and 3 mT, 50 Hz) exposure on synaptic functions in the developing brain. Rats were treated with chronic exposure to MF during two critical periods of brain development, i.e. in utero during the second gestation week or as newborns for 7 days starting 3 days after birth, respectively. Excitability and plasticity of neocortical and hippocampal areas were tested on brain slices by analyzing extracellular evoked field potentials. We demonstrated that the basic excitability of hippocampal slices (measured as amplitude of population spikes) was increased by both types of treatment (fetal 0.5 mT, newborn 3 mT). Neocortical slices seemed to be responsive mostly to the newborn treatment, the amplitude of excitatory postsynaptic potentials was increased. Fetal ELF-MF exposure significantly inhibited the paired-pulse depression (PPD) and there was a significant decrease in the efficacy of LTP (long-term potentiation induction) in neocortex, but not in hippocampus. On the other hand, neonatal treatment had no significant effect on plasticity phenomena. Results demonstrated that ELF-MF has significant effects on basic neuronal functions and synaptic plasticity in brain slice preparations originating from rats exposed either in fetal or in newborn period.


Subject(s)
Excitatory Postsynaptic Potentials/radiation effects , Hippocampus , Magnetic Fields , Neocortex , Synapses/radiation effects , Age Factors , Analysis of Variance , Animals , Animals, Newborn , Dose-Response Relationship, Radiation , Embryo, Mammalian , Hippocampus/cytology , Hippocampus/embryology , Hippocampus/growth & development , In Vitro Techniques , Male , Neocortex/cytology , Neocortex/embryology , Neocortex/growth & development , Rats , Rats, Wistar
10.
Int J Sport Nutr Exerc Metab ; 23(6): 624-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23881074

ABSTRACT

The aim of this work was to examine the link between the physical-perceptual characteristics of nutritional supplements and their expected effectiveness in enhancing sport performance. Participants (n = 267) ranked nine images of fictive nutritional supplements, varying in shape, color, and route of administration (e.g., pill, powder, lotion, etc.), in ranked- order of expected effectiveness. They performed the task three times, (1) for strength, (2) endurance, and (3) for concentration. Results have revealed that the perceived effectiveness of the supplements was statistically significantly different for the three types of performances (p < .001). A significant interpersonal variability was observed in the ranking-order of the supplements. The findings reveal that perceptual characteristics of 'believed to be nutritional supplements', aimed at sport performance enhancement, influence their perceived effectiveness. Future inquiries in sport nutrition should examine the relationship between expected and experienced effectiveness of various nutritional supplements in enhancing sport performance.


Subject(s)
Athletic Performance/psychology , Dietary Supplements , Physical Endurance , Sports Nutritional Physiological Phenomena , Adolescent , Athletic Performance/physiology , Female , Humans , Male , Motor Activity/physiology , Nutritional Status , Sports , Young Adult
11.
J Health Psychol ; 18(6): 773-81, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23520346

ABSTRACT

The cross-sectional study aimed at the psychometric evaluation of the Modern Health Worries Scale in adolescents and the exploration of the relationship among modern health worries, somatosensory amplification, health anxiety, and somatic symptoms. A total of 480 secondary school students (aged between 14 and 19 years) completed a set of questionnaires. Four-factor structure of the scale was confirmed by confirmatory factor analysis. Modern health worries were connected to somatosensory amplification and health anxiety, and somatosensory amplification and health anxiety were partial mediators of the connection between modern health worries and somatic symptoms. Perceived vulnerability (conceptualized as somatosensory amplification and health anxiety) appears to build a "social-cognitive-emotional bridge" between symptoms and modern health worries.


Subject(s)
Anxiety/etiology , Somatosensory Disorders/psychology , Adolescent , Age Factors , Anxiety/epidemiology , Cross-Sectional Studies , Factor Analysis, Statistical , Female , Health Status , Humans , Male , Psychometrics , Somatosensory Disorders/epidemiology , Surveys and Questionnaires , Young Adult
12.
Int J Hyg Environ Health ; 216(3): 362-70, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22698789

ABSTRACT

INTRODUCTION: The tendency of experiencing unpleasant symptoms in the proximity of working electric devices is called idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF). Evidence about psychophysiological backgrounds of the phenomenon (i.e., detection ability and mechanisms of symptom generation) is not yet conclusive. METHODS: Participants of the provocation experiment were 29 individuals with self-reported IEI-EMF and 42 control persons. Participants completed questionnaires (symptom expectations, somatosensory amplification - SSAS, modern health worries radiation subscale - MHW-R), and attempted to detect the presence of 50 Hz 0.5 mT magnetic field (MF) directed to their right arm in 20 subsequent 1-min sessions. Heart rate was also recorded and various indices of heart rate variability (HF, LF/HF, SDNN) were calculated. RESULTS: Using the methodology of the signal detection theory, individuals with IEI-EMF as opposed to the control group showed a higher than random detection performance (d' differed slightly but statistically significantly from zero), and they used a significantly lower criterion (ß value) when deciding about the presence of the MF. Detection sessions followed by correct decisions (hits or correct rejections) were characterized by higher HRV (SDNN and HF indices) than periods followed by errors (misses or false alarms). Previous expectations and affiliation to the IEI-EMF group were significant predictors of symptoms reported following exposure. IEI-EMF was closely related to MHW-R and SSAS scores. CONCLUSION: Detection of MF might be possible for people with IEI-EMF to some extent. Although heightened sensibility to MFs may play a role in the development and/or in the perpetuance of the IEI-EMF phenomenon, symptoms attributed to the MF seem to be mainly of psychogenic origin.


Subject(s)
Magnetic Fields , Multiple Chemical Sensitivity/diagnosis , Somatoform Disorders/diagnosis , Adolescent , Adult , Electrocardiography , Female , Heart Rate , Humans , Male , Multiple Chemical Sensitivity/physiopathology , Multiple Chemical Sensitivity/psychology , Somatoform Disorders/physiopathology , Somatoform Disorders/psychology , Surveys and Questionnaires , Young Adult
13.
Scand J Psychol ; 53(2): 144-9, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21883257

ABSTRACT

Relationship among modern health worries (MHWs), somatosensory amplification (SSA), and attributional styles was investigated in a cross-sectional questionnaire study. A total of 99 university students, 104 patients visiting their General Practitioners, and 102 future alternative therapists completed questionnaires assessing MHWs, SSA, negative affect (NA), and psychological, somatic and normalizing (environmental) attribution styles. Significant correlation between SSA and MHWs was found in all three samples. MHWs and psychological attribution style were significantly associated with Complementary and Alternative Medicine (CAM)-orientation in the regression equation even after controlling for SSA, NA, and sociodemographic variables. MHWs were independent from any attribution styles in the student and patient samples, while significant correlations with all three styles were found in the CAM group. Previously described association between MHWs and SSA was replicated in three different samples. The connection between MHWs and CAM preference seems to be independent from SSA, NA or any particular attribution style.


Subject(s)
Anxiety/psychology , Attitude to Health , Complementary Therapies/psychology , Adult , Aged , Cross-Sectional Studies , Environment , Female , Humans , Male , Middle Aged , Social Perception , Students , Surveys and Questionnaires
14.
Scand J Psychol ; 52(2): 174-8, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21029108

ABSTRACT

The theoretically hypothesized connection between modern health worries (MHWs) and somatosensory amplification (SSA), as well as the factor structure of the Hungarian version of the MHW scale were investigated in a cross-sectional questionnaire study. A total of 163 university students (mean age = 21.3± 2.70 yrs; 44.2% male) and 145 patients (mean age = 49.4±17.51 yrs; 31.7% male) visiting their general practitioners (GPs) completed questionnaires assessing MHWs, SSA, subjective somatic symptoms (PHQ-15), and trait anxiety (STAI-T). The previously described four-factor structure of the MHW scale was confirmed using confirmatory factor analysis (CFA). In the linear regression analysis, participants' age and SSA scores were positively related to MHWs even after controlling for gender, anxiety, and subjective somatic symptom scores. The conclusions are that: MHWs are indicators of cognitive, behavioral and social level of sensitization for health-related concerns; SSA can provide the somatic background process for generation and/or misattribution of subjective somatic symptoms; better understanding of the cognitive-emotional background of MHWs could help to determine possible interventions.


Subject(s)
Anxiety/psychology , Attitude to Health , Somatoform Disorders/psychology , Adult , Age Factors , Aged , Cross-Sectional Studies , Factor Analysis, Statistical , Female , Humans , Hungary , Male , Middle Aged , Regression Analysis , Surveys and Questionnaires
15.
Brain Res ; 1353: 159-67, 2010 Sep 24.
Article in English | MEDLINE | ID: mdl-20674554

ABSTRACT

Imitation in humans has been attributed to increased activation of the mirror neuron system, but there is no neural model to explain reciprocal communication. In this study, we investigated whether reciprocal, communicative, imitative exchanges activate the same neural system as imitation of simple movements, and whether the neural network subserving communication is lateralized. Fifteen participants were tested using functional magnetic resonance imaging with an online interactive-imitative paradigm while they performed finger movements for three different purposes: (1) to imitate the experimenter, (2) to elicit an imitation from the experimenter, and (3) to simply perform the movement. Subtraction analysis (imitation > movement, initiation > movement) revealed the activation of a strongly lateralized network, where the infra-parietal lobule (IPL) activation was lateralized to the left, while the infero-frontal gyrus (IFG) activation was to the right. It is concluded that imitation in a communicative paradigm recruits a lateralized network, with left fronto- and right parietal activation, that overlaps with a network that subserves understanding of an Other's intentions in relation to the Self. This finding lends plausibility to the suggestion that the neural network for imitation evolved to support interpersonal communication.


Subject(s)
Brain Mapping , Communication , Frontal Lobe/physiology , Imitative Behavior/physiology , Adolescent , Adult , Female , Frontal Lobe/blood supply , Functional Laterality , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Neural Pathways/blood supply , Neural Pathways/physiology , Oxygen/blood , Young Adult
16.
Int J Hyg Environ Health ; 213(5): 387-94, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20538519

ABSTRACT

INTRODUCTION: 'Idiophatic Environmental Intolerance attributed to electromagnetic fields' (IEI-EMF) refers to the perception of subjective symptoms during or following EMF exposure. IEI-EMF has become disproved to be a mostly biologic entity by now, and evidences accumulate to support the role of nocebo effect in the phenomenon. The two aims of this study were to demonstrate the significant role of the nocebo effect in physical symptoms reported at 50Hz frequency of EMF exposure, as well as to explore some psychological factors which may predispose to IEI-EMF. METHODS: A total of 40 volunteer university students have completed a battery of psychological questionnaires (expectations; IEI-EMF; state anxiety - STAI-S; dispositional optimism - LOT-R; somatisation - PHQ-15; somatosensory amplification - SSAS) before, and checklists of physical symptoms during sham exposure to "weak" and "strong" EMFs, respectively. Participants were also asked about the extent to which they had perceived the presence of the presumed EMF. RESULTS: Participants with higher IEI-EMF scores expected and experienced more symptoms. Suggestion of stronger EMF exposure resulted in larger symptom scores and enhanced EMF-perception as compared to the presumed weaker exposure. Experienced symptom scores were predicted primarily by somatisation scores, whereas self-rating of IEI-EMF was predicted by somatosensory amplification scores. CONCLUSION: The results confirm that there is considerable nocebo effect in symptom reports related to 50Hz frequency EMFs. IEI-EMF seems to be formed through a vicious circle of psychosocial factors, such as enhanced perception of risk and expectations, self-monitoring, somatisation and somatosensory amplification, causalization and misattribution.


Subject(s)
Electromagnetic Fields/adverse effects , Multiple Chemical Sensitivity/psychology , Adult , Anxiety/psychology , Female , Humans , Male , Perceptual Disorders/psychology , Placebo Effect , Somatoform Disorders/psychology , Young Adult
17.
Brain Res Bull ; 81(1): 92-9, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-19883742

ABSTRACT

It is believed that different electromagnetic fields do have beneficial and harmful biological effects. The aim of the present work was to study the long-term consequences of 50 Hz electromagnetic field (ELF-EMF) exposure with special focus on the development of chronic stress and stress-induced psychopathology. Adult male Sprague-Dawley rats were exposed to ELF-EMF (50 Hz, 0.5 mT) for 5 days, 8h daily (short) or for 4-6 weeks, 24h daily (long). Anxiety was studied in elevated plus maze test, whereas depression-like behavior of the long-treated group was examined in the forced swim test. Some days after behavioral examination, the animals were decapitated among resting conditions and organ weights, blood hormone levels as well as proopiomelanocortin mRNA level from the anterior lobe of the pituitary gland were measured. Both treatments were ineffective on somatic parameters, namely none of the changes characteristic to chronic stress (body weight reduction, thymus involution and adrenal gland hypertrophy) were present. An enhanced blood glucose level was found after prolonged ELF-EMF exposure (p=0.013). The hormonal stress reaction was similar in control and short-term exposed rats, but significant proopiomelanocortin elevation (p<0.000) and depressive-like behavior (enhanced floating time; p=0.006) were found following long-term ELF-EMF exposure. Taken together, long and continuous exposure to relatively high intensity electromagnetic field may count as a mild stress situation and could be a factor in the development of depressive state or metabolic disturbances. Although we should stress that the average intensity of the human exposure is normally much smaller than in the present experiment.


Subject(s)
Adrenocorticotropic Hormone/blood , Anxiety/physiopathology , Corticosterone/blood , Depression/physiopathology , Electromagnetic Fields/adverse effects , Stress, Psychological/physiopathology , Animals , Anxiety/blood , Anxiety/etiology , Blood Glucose/physiology , Body Weight/physiology , Chronic Disease , Depression/blood , Depression/etiology , Male , Neuropsychological Tests , Pituitary Gland, Anterior/physiopathology , Pro-Opiomelanocortin/metabolism , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Stress, Psychological/blood , Stress, Psychological/etiology , Time Factors
18.
Psychiatr Hung ; 24(4): 282-95, 2009.
Article in Hungarian | MEDLINE | ID: mdl-19949246

ABSTRACT

In this narrative review the anecdotical, empirical and theoretical knowledge about expectations and effects evoked by perceptual characteristics of pharmaceuticals is summarised within the framework of the so-called non-specific effects. The most important factors (such as prestige, brand, dosage, way of administration, taste, size/shape, colour of curatives) and their impact are discussed in details, based on all available sources in literature. After the summary of the known explanations regarding the origins of expectations and effects (conditioning, social learning, culture), an integrated approach is proposed. When taking an unknown pharmaceutical, people's expectations rely on culturally and socially mediated knowledge and symbolism. These expectations can drastically change later, due to personal experiences with the effects and look-and-feel of a given drug. Possible practical applications (increasing effectivity of medicines, minimizing side effects, improving compliance, preventing confounding) are also proposed as part of a new approach called intelligent medicine designing.


Subject(s)
Color , Pharmaceutical Preparations , Taste , Drug Administration Routes , Form Perception , Humans , Medication Adherence , Pharmaceutical Preparations/administration & dosage , Placebo Effect , Placebos
19.
Bioelectromagnetics ; 30(8): 631-40, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19572331

ABSTRACT

The effects of electromagnetic fields (EMFs) on living organisms are recently a focus of scientific interest, as they may influence everyday life in several ways. Although the neural effects of EMFs have been subject to a considerable number of investigations, the results are difficult to compare since dissimilar exposure protocols have been applied on different preparations or animals. In the present series of experiments, whole rats or excised rat brain slices were exposed to a reference level-intensity (250-500 microT, 50 Hz) EMF in order to examine the effects on the synaptic efficacy in the central nervous system. Electrophysiological investigation was carried out ex vivo, on neocortical and hippocampal slices; basic synaptic functions, short- and long-term plasticity and seizure susceptibility were tested. The most pronounced effect was a decrease in basic synaptic activity in slices treated directly ex vivo observed as a diminution in amplitude of evoked potentials. On the other hand, following whole-body exposure an enhanced short- and long-term synaptic facilitation in hippocampal slices and increased seizure susceptibility in neocortical slices was also observed. However, these effects seem to be transient. We can conclude that ELF-EMF exposure exerts significant effects on synaptic activity, but the overall changes may strongly depend on the synaptic structure and neuronal network of the affected region together with the specific spatial parameters and constancy of EMF.


Subject(s)
Brain/radiation effects , Electromagnetic Fields , Seizures/etiology , Synapses/radiation effects , Action Potentials , Animals , Brain/physiopathology , In Vitro Techniques , Male , Neuronal Plasticity , Rats , Rats, Wistar
20.
Int J Dev Neurosci ; 26(7): 713-21, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18678240

ABSTRACT

Cerebral dysgeneses are in the background of several neurological and mental disturbances. The aim of the present study was to investigate structural and activity changes following disturbed postnatal neuronal development in mice. Newborn C57Bl6 mice were exposed to 5-bromo-2'-deoxyuridine (BrdU: daily 50 microg/g body weight) during a period between postnatal days P0-P5 or P0-P11, respectively, and neuronal malformation and malfunctioning of somatosensory (barrel field) cortex was analyzed in adolescent animals. Alterations in histological architecture of interneuronal and glial elements were studied and correlated with electrophysiological modifications. Between P30 and P35 days litters underwent ex vivo electrophysiological experiments to examine the changes in basic excitability and in synaptic efficacy. Parallel immunohistochemistry was performed to detect BrdU, GABA and GFAP. There were no BrdU immunopositive cell nuclei in control animals, but marked staining was observed in both BrdU treated groups. Lessening in the number of GABAergic neurons was observed in the treated groups. GFAP immunohistochemical analysis has shown an increased number of activated astroglial cells in treated animals. Reduction of the number of GABAergic neurons was observed in the treated groups. Electrophysiological recordings on cortical slices showed increased excitability in the treated groups.


Subject(s)
Bromodeoxyuridine/toxicity , Somatosensory Cortex/growth & development , Action Potentials/physiology , Aging/physiology , Animals , Animals, Newborn , Antimetabolites/toxicity , Biomarkers/metabolism , Female , Glial Fibrillary Acidic Protein/metabolism , Gliosis/pathology , Gliosis/physiopathology , Immunohistochemistry , Interneurons/drug effects , Interneurons/pathology , Male , Mice , Mice, Inbred C57BL , Neuroglia/drug effects , Neuroglia/pathology , Somatosensory Cortex/drug effects , Somatosensory Cortex/physiopathology , Somatosensory Disorders/chemically induced , Somatosensory Disorders/pathology , Somatosensory Disorders/physiopathology , Synaptic Transmission/drug effects , Synaptic Transmission/physiology , gamma-Aminobutyric Acid/metabolism
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