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Magnetic Therapy Research: Psychological & Behavioral Effects

Behavioral

 

Cognitive

 

Labyrinthectomy abolishes the behavioral and neural response of rats to a high-strength static magnetic field

Cason AM, Kwon B, Smith JC, Houpt TA. Department of Biological Science, Program in Neuroscience, The Florida State University, Tallahassee, Florida 32306-4340, United States.

Vertigo is a commonly-reported side effect of exposure to the high magnetic fields found in magnetic resonance imaging machines. Although it has been hypothesized that high magnetic fields interact with the vestibular apparatus of the inner ear, there has been no direct evidence establishing its role in magnet-induced vertigo. Our laboratory has shown that following exposure to high magnetic fields, rats walk in circles, acquire a conditioned taste aversion (CTA), and express c-Fos in vestibular and visceral relays of the brainstem, consistent with vestibular stimulation and vertigo or motion sickness. To determine if the inner ear is required for these effects, rats were chemically labyrinthectomized with sodium arsanilate and tested for locomotor circling, CTA acquisition, and c-Fos induction after exposure within a 14.1 T magnet. Intact rats circled counterclockwise after 30-min exposure to 14.1 T, but labyrinthectomized rats showed no increase in circling after magnetic field exposure. After 3 pairings of 0.125% saccharin with 30-min exposure at 14.1 T, intact rats acquired a profound CTA that persisted for 14 days of extinction testing; labyrinthectomized rats, however, did not acquire a CTA and showed a high preference for saccharin similar to sham-exposed rats. Finally, significant c-Fos was induced in the brainstem of intact rats by 30-min exposure to 14.1 T, but magnetic field exposure did not elevate c-Fos in labyrinthectomized rats above sham-exposed levels. These results demonstrate that an intact inner ear is necessary for all the observed effects of exposure to high magnetic fields in rats.

Cason AM, Kwon B, Smith JC, Houpt TA (April 2009). "Labyrinthectomy abolishes the behavioral and neural response of rats to a high-strength static magnetic field." Physiology & Behavior 97(1):36-43. PMID: 19419674

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The use of slow-frequency transcranial magnetic stimulation in the treatment of depression at Brasilia University Hospital: preliminary findings.

Brasil-Neto JP, Boechat-Barros R, da Mota-Silveira DA.

Laboratorio de Neurobiologia, Departamento de Ciencias Fisiologicas, Universidade de Brasilia, Brasilia, DF, Brasil.

This paper reports the use of slow frequency transcranial magnetic stimulation of the right pre-frontal cortex in three patients with a diagnosis of major depressive episode according to the DSM-IV classification. There was a significant improvement in two patients, with a decrease of over 50% in the Hamilton Scale scores- 17 items. Possible indications and limitations of this therapeutic tool are discussed, as well as socio-economic aspects of this new treatment.

Arq Neuropsiquiatr. 2003 Mar;61(1):83-6. Epub 2003 Apr 16.

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Transcranial magnetic stimulation as therapy for depression and other disorders.

Kirkcaldie MT, Pridmore SA, Pascual-Leone A.

Department of Anatomy and Physiology, University of Tasmania, Hobart, Australia.

OBJECTIVE: To provide an overview of the progress and prospects of transcranial magnetic stimulation as a psychiatric therapy for depression.

METHOD: Published and unpublished studies of the usefulness of transcranial magnetic stimulation as a therapy for depression were assessed, and characterised in terms of a consistent measure of dosage. Additional information was obtained through correspondence, personal meetings and visits to facilities.

RESULTS: Transcranial magnetic stimulation, a means for inducing small regional currents in the brain, has been used in clinical neurology for some time, and can be used on conscious subjects with minimal side-effects. Early researchers noticed transient mood effects on people receiving this treatment, which prompted several inconclusive investigations of its effects on depressed patients. More recently, knowledge of functional abnormalities associated with depression has led to trials using repetitive transcranial magnetic stimulation to stimulate underactive left prefrontal regions, an approach which has produced short-term benefits for some subjects. The higher dosage delivered by high-frequency repetitive transcranial magnetic stimulation appears to produce greater benefits; scope exists for more conclusive studies based on extended treatment periods.

CONCLUSIONS: Repetitive transcranial magnetic stimulation is a promising technology. The reviewed evidence indicates that it may be useful in the treatment of depression, and perhaps other disorders which are associated with regional hypometabolism. Should repetitive transcranial magnetic stimulation prove an effective, non-invasive, drug-free treatment for depression, a range of disorders could be similarly treatable.

Aust N Z J Psychiatry. 1997 Apr;31(2):264-72.

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Low-field magnetic stimulation in bipolar depression using an MRI-based stimulator.

Rohan M, Parow A, Stoll AL, Demopulos C, Friedman S, Dager S, Hennen J, Cohen BM, Renshaw PF.

Brain Imaging Center, McLean Hospital, Belmont, MA 02478, USA. mrohan@mclean.harvard.edu

OBJECTIVE: Anecdotal reports have suggested mood improvement in patients with bipolar disorder immediately after they underwent an echo-planar magnetic resonance spectroscopic imaging (EP-MRSI) procedure that can be performed within clinical MR system limits. This study evaluated possible mood improvement associated with this procedure.

METHOD: The mood states of subjects in an ongoing EP-MRSI study of bipolar disorder were assessed by using the Brief Affect Scale, a structured mood rating scale, immediately before and after an EP-MRSI session. Sham EP-MRSI was administered to a comparison group of subjects with bipolar disorder, and actual EP-MRSI was administered to a comparison group of healthy subjects. The characteristics of the electric fields generated by the EP-MRSI scan were analyzed.

RESULTS: Mood improvement was reported by 23 of 30 bipolar disorder subjects who received the actual EP-MRSI examination, by three of 10 bipolar disorder subjects who received sham EP-MRSI, and by four of 14 healthy comparison subjects who received actual EP-MRSI. Significant differences in mood improvement were found between the bipolar disorder subjects who received actual EP-MRSI and those who received sham EP-MRSI, and, among subjects who received actual EP-MRSI, between the healthy subjects and the bipolar disorder subjects and to a lesser extent between the unmedicated bipolar disorder subjects and the bipolar disorder subjects who were taking medication. The electric fields generated by the EP-MRSI scan were smaller (0.7 V/m) than fields used in repetitive transcranial magnetic stimulation (rTMS) treatment of depression (1-500 V/m) and also extended uniformly throughout the head, unlike the highly nonuniform fields used in rTMS. The EP-MRSI waveform, a 1-kHz train of monophasic trapezoidal gradient pulses, differed from that used in rTMS.

CONCLUSIONS: These preliminary data suggest that the EP-MRSI scan induces electric fields that are associated with reported mood improvement in subjects with bipolar disorder. The findings are similar to those for rTMS depression treatments, although the waveform used in EP-MRSI differs from that used in rTMS. Further investigation of the mechanism of EP-MRSI is warranted.

Am J Psychiatry. 2004 Jan;161(1):93-8.

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Magnetic fields mimic the behavioral effects of REM sleep deprivation in humans.

Sandyk R, Tsagas N, Anninos PA, Derpapas K.

Democrition University of Thrace, Department of Medical Physics, Greece.

The discovery of rapid eye movement (REM) sleep by Aserinsky and Kleitman in 1953 initiated the impetus for sleep research and specifically the investigations of the effects of REM sleep deprivation (RSD) on animal and human behavior. The behavioral effects of RSD include the enhancement of motivational and "drive"-related behaviors. In laboratory animals, RSD has been reported to increase appetite, sexual behavior, aggressiveness, and locomotor activity. Moreover, RSD reportedly improves mood in patients with endogenous depression and heightens appetite and sexual interest in normal subjects. Since "drive"-related behaviors are thought to involve activation of limbic dopaminergic reward sites, RSD may enhance motivational behaviors through an action on limbic dopaminergic functions. In the present communication, we present two patients (one with multiple sclerosis and the other with Parkinson's disease) in whom treatment with magnetic fields produced behavioral effects which paralleled those observed in REM-sleep-deprived animals and humans. We propose, therefore, that the behavioral and mental effects of treatment with magnetic fields may be mediated via RSD and, by inference, involve activation of limbic dopaminergic reward sites.

Int J Neurosci. 1992 Jul-Aug;65(1-4):61-8.

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Chronic exposure to 2.9 mT, 40 Hz magnetic field reduces melatonin concentrations in humans.

Karasek M, Woldanska-Okonska M, Czernicki J, Zylinska K, Swietoslawski J.

Laboratory of Electron Microscopy, Medical University of Lodz, Poland. Micha.7497401@pharmanet.com.pl

Diurnal rhythm of serum melatonin concentrations was estimated in 12 men with low back pain syndrome before and after exposure to a very low-frequency magnetic field (2.9 mT, 40 Hz, square wave, bipolar). Patients were exposed to the magnetic field for 3 weeks (20 min per day, 5 days per week) either in the morning (at 10:00 hr) or in the late afternoon (at 18:00 hr). Significant depression in nocturnal melatonin rise was observed regardless of the time of exposure. This phenomenon was characteristic for all the subjects, although the percent of inhibition of melatonin secretion varied among the studied individuals.

J Pineal Res. 1998 Dec;25(4):240-4.

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Improvement of right hemispheric functions in a child with Gilles de la Tourette's syndrome by weak electromagnetic fields.

Sandyk R.

NeuroCommunication Research Laboratories, Danbury, CT 06811, USA.

Gilles de la Tourette's syndrome (GTS) is a chronic, familial neuropsychiatric disorder of unknown etiology characterized clinically by the occurrence of motor and vocal tics and by the presence of a variety of neurobehavioral and neurocognitive abnormalities including hyperactivity, self-multilatory behavior, obsessive-compulsive behavior, learning disabilities, and conduct disorder. On the basis of neuropsychological assessments it has been suggested that GTS is associated with greater right than left hemispheric dysfunction which accounts for decrements in visuospatial, visuoconstructional and visuomotor skills in these patients. Recent case studies have demonstrated that extracranial application of electromagnetic fields (EMFs) in the picotesla (pT) range intensity improves visuospatial and visuoperceptive functions in patients with neurodegenerative disorders including Parkinson's disease, multiple sclerosis and Alzheimer's disease. I now present a 6 1/2 year old boy with GTS in whom this treatment modality produced, in addition to symptomatic behavioral improvement, also improvement in visuoconstructional and visuomotor skills as evidenced on various drawing tasks particularly copy of the Rey-Osterrieth Complex Figure, a task which is especially vulnerable to right hemispheric functions. These findings suggest that pT range EMFs may be useful for the treatment of GTS and related disorders and also reverse some of the cognitive impairments associated with the disease which are related to right hemispheric dysfunction and which contribute to learning disabilities in these patients.

Int J Neurosci. 1995 Apr;81(3-4):199-213.

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Effects of magnetic field exposure on open field behaviour and nociceptive responses in mice.

Del Seppia C, Mezzasalma L, Choleris E, Luschi P, Ghione S.

Institute of Clinical Physiology, CNR, via Moruzzi 1, 56124 Pisa, Italy. dscri@ifc.cnr.it

Results of previous studies have shown that nociceptive sensitivity in male C57 mice is enhanced by exposure to a regular 37 Hz or an irregularly varying (<1 Hz) electromagnetic field. In order to test whether these fields affect more generally mouse behaviour, we placed Swiss CD-1 mice in a novel environment (open field test) and exposed them for 2 h to these two different magnetic field conditions. Hence, we analysed how duration and time course of various behavioural patterns (i.e. exploration, rear, edge chew, self-groom, sit, walk and sleep) and nociceptive sensitivity had been affected by such exposure. Nociceptive sensitivity was significantly greater in magnetically treated mice than in controls. The overall time spent in exploratory activities was significantly shorter in both magnetically treated groups (< 1 Hz, 33% and 37 Hz, 29% of total time), than in controls (42%). Conversely, the time spent in sleeping was markedly longer in the treated groups (both 27% of total time) than in controls (11%). These results suggest that exposure to altered magnetic fields induce a more rapid habituation to a novel environment.

Behav Brain Res. 2003 Sep 15;144(1-2):1-9.

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Biomagnetics: Considerations Relevant to Manned Space Flight, NASA Contract Report CR-889.

Research by Halpern, M. as reported by Busby, D.E.

National Aeronautics and Space Administration, Washington, D.C.

Magnetic field reduction. In an early study to investigate the possible effects of reduced magnetic fields on astronauts as a result of space travel, mice were kept in mu-metal containers which greatly reduced exposure to the earth's magnetic field. "In contrast to the normally thriving control[s] ... the mice in the mu-metal cylinders have presented a characteristic, rather bizarre, picture." "At an early age, large numbers of mu-metal mice have become docile and inactive. Many mice exhibited the highly unusual behavior of lying on their back for prolonged periods of time."

NASA Contract Rep NASA CR. 1967 Nov;:1-57.

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A detailed ethological analysis of the mouse open field test: effects of diazepam, chlordiazepoxide and an extremely low frequency pulsed magnetic field.

Choleris E, Thomas AW, Kavaliers M, Prato FS.

Room 9222D, Department of Psychology, Social Science Center, University of Western Ontario, London, Ontario, Canada N6A 5C2. choleris@julian.uwo.ca

The open field test (OFT) is a widely used procedure for examining the behavioral effects of drugs and anxiety. Detailed ethological assessments of animal behavior are lacking. Here we present a detailed ethological assessment of the effects of acute treatment with the benzodiazepines, diazepam (DZ, 1.5mg/kg) and chlordiazepoxide (CDP, 5.0 and 10.0mg/kg), as well as exposure to a non-pharmacological agent, a specific pulsed extremely low frequency magnetic field (MAG) on open field behavior. We examined the duration, frequency and time course of various behaviors (i.e. exploration, walk, rear, stretch attend, return, groom, sit, spin turn, jump and sleep) exhibited by male mice in different regions of a novel open field. Both DZ and CDP consistently reduced the typical anxiety-like behaviors of stretch attend and wall-following (thigmotaxis), along with that of an additional new measure: 'returns', without producing any overall effects on total locomotion. The drugs also differed in their effects. CDP elicited a shift in the locomotor pattern from a 'high explore' to a 'high walk', while DZ mainly elicited alterations in sit and groom. The MAG treatment was repeated twice with both exposures reducing horizontal and vertical (rearing) activity and increasing grooming and spin turns. However, the anxiety-like behaviors of stretch attend and return were marginally reduced by only the first exposure. We conclude that a detailed ethological analysis of the OFT allows not only the detection of specific effects of drugs and non-pharmacological agents (i.e. pulsed magnetic field) on anxiety-like behaviors, but also permits the examination of non-specific effects, in particular those on general activity.

Neurosci Biobehav Rev. 2001 May;25(3):235-60.

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A subterranean mammal uses the magnetic compass for path integration

Kimchi T, Etienne AS, Terkel J.

*Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.

Path integration allows animals to navigate without landmarks by continuously processing signals generated through locomotion. Insects such as bees and ants have evolved an accurate path integration system, assessing and coding rotations with the help of a general directional reference, the sun azimuth. In mammals, by contrast, this process can take place through purely idiothetic (mainly proprioceptive and vestibular) signals. However, without any stable external reference for measuring direction, path integration is highly affected by cumulative errors and thus has been considered so far as valid only for short-distance navigation. Here we show through two path integration experiments (homing and shortcut finding) that the blind mole rat assesses direction both through internal signals and by estimating its heading in relation to the earth's magnetic field. Further, it is shown that the greater the circumvolution and length of the traveled path, the more the animal relies on the geomagnetic field. This path integration system strongly reduces the accumulation of errors due to inaccuracies in the estimation of rotations and thus allows the mole rat to navigate efficiently in darkness, without the help of any landmark, over both short and long distances.

Proc Natl Acad Sci U S A. 2004 Jan 19.

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Rapporteur report: weak field interactions in the central nervous system.

Saunders RD.

National Radiological Protection Board, Chilton, Didcot, Oxfordshire, UK. richard.saunders@nrpb.org

Experimental evidence was presented of the interaction of extremely low frequency (ELF) physiologically weak electric fields (that is, internal fields of around 1-1000 mV m(-1)) with tissues of the central nervous system and the consequences of this for visual and cognitive function. These internal fields are higher than those induced in the body by exposure to environmental EMFs, but are small compared to nerve excitation thresholds. Two papers considered the effect of weak electric fields directly applied to hippocampal tissue in vitro on neuronal excitability assessed from evoked responses and on the modulation of neural network activity involving large numbers of individual neurons. A review was presented of the effects on electrical measures of perceptual and cognitive processes and on the performance of various behavioural tasks in volunteers exposed to electromagnetic fields. Finally, two papers addressed the visual perception of flickering light--phosphenes--in volunteers exposed to ELF magnetic fields. The first examined possible physiological origins of this phenomenon and the second assessed the induced electric fields and currents in the retina, using complex dosimetric modelling. These papers were discussed in several plenary sessions and in one breakout group, all of which are briefly summarized in this report.

Radiat Prot Dosimetry. 2003; 106(4): 357-61.

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Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields.

Persinger MA, Healey F.

Behavioral Neuroscience Program, Department of Psychology, Laurentian University, Sudbury, Ontario P3E 2C6.

This experiment was designed to test the hypothesis that the sensed presence, the feeling of a proximal sentient being, can be evoked within the laboratory. Under double-blind conditions, 48 university men and women were exposed to weak (100 nT to 1 muT), complex, pulsed magnetic fields that were applied primarily over the right temporoparietal region, primarily over the left temporoparietal region, or equally across both hemispheres (one treatment per group) for 20 minutes while wearing opaque goggles in a very quiet room. A fourth group was exposed to a sham-field condition. Subjects who received greater stimulation over the right hemisphere or equal stimulation across both hemispheres reported more frequent incidences of presences, fears, and odd smells than did the subjects who received greater stimulation over the left hemisphere or who were exposed to the sham-field condition. The results suggest that the sensed presence is subject to experimental manipulation. This experimental procedure could be employed to explore the idea that the experience of a sensed presence is a resident property of the human brain and may be the fundamental source for phenomena attributed to visitations by gods, spirits, and other ephemeral phenomena.

J Nerv Ment Dis. 2002 Aug;190(8):533-41.

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Electromagnetic field of mobile phones affects visual event related potential in patients with narcolepsy.

Jech R, Sonka K, Ruzicka E, Nebuzelsky A, Bohm J, Juklickova M, Nevsimalova S.

Department of Neurology, 1st Medical Faculty, Charles University, Prague, Czech Republic. panther@tremor.anet.cz

The effects of the mobile phone (MP) electromagnetic fields on electroencephalography (EEG) and event-related potentials (ERP) were examined. With regard to the reported effects of MP on sleep, 22 patients with narcolepsy-cataplexy were exposed or sham exposed for 45 min to the MP (900 MHz, specific absorption rate 0.06 W/kg) placed close to the right ear in a double blind study. There were no changes of the EEG recorded after the MP exposure. A subgroup of 17 patients was studied on visual ERP recorded during the MP exposure. Using an adapted "odd-ball" paradigm, each patient was instructed to strike a key whenever rare target stimuli were presented. There were three variants of target stimuli (horizontal stripes in (i) left, (ii) right hemifields or (iii) whole field of the screen). The exposure enhanced the positivity of the ERP endogenous complex solely in response to target stimuli in the right hemifield of the screen (P < 0.01). The reaction time was shortened by 20 ms in response to all target stimuli (P < 0.05). In conclusion, the electromagnetic field of MP may suppress the excessive sleepiness and improve performance while solving a monotonous cognitive task requiring sustained attention and vigilance. Copyright 2001 Wiley-Liss, Inc.

Bioelectromagnetics. 2001 Oct;22(7):519-28.

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Changes in brain memory functions as affected by a constant magnetic field.

Konovalov VF, Serikov IS.

Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino.

Effects of CMF on memory processes in adult volunteers (non-sleep vs hypnotic condition) has been studied at laboratory and clinical conditions. The results point out that CMF changes the interhemispheric relations and result in memory malfunction. The malfunction of memory activity in volunteers after action of CMF was influenced by two factors: magnetic field position under different brain areas and functional status of volunteers: awake or hypnotic.

Radiats Biol Radioecol. 1998 Sep-Oct;38(5):769-74.

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