1
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Echeverria V, Mendoza C, Iarkov A. Nicotinic acetylcholine receptors and learning and memory deficits in Neuroinflammatory diseases. Front Neurosci 2023; 17:1179611. [PMID: 37255751 PMCID: PMC10225599 DOI: 10.3389/fnins.2023.1179611] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 04/07/2023] [Indexed: 06/01/2023] Open
Abstract
Animal survival depends on cognitive abilities such as learning and memory to adapt to environmental changes. Memory functions require an enhanced activity and connectivity of a particular arrangement of engram neurons, supported by the concerted action of neurons, glia, and vascular cells. The deterioration of the cholinergic system is a common occurrence in neurological conditions exacerbated by aging such as traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), Alzheimer's disease (AD), and Parkinson's disease (PD). Cotinine is a cholinergic modulator with neuroprotective, antidepressant, anti-inflammatory, antioxidant, and memory-enhancing effects. Current evidence suggests Cotinine's beneficial effects on cognition results from the positive modulation of the α7-nicotinic acetylcholine receptors (nAChRs) and the inhibition of the toll-like receptors (TLRs). The α7nAChR affects brain functions by modulating the function of neurons, glia, endothelial, immune, and dendritic cells and regulates inhibitory and excitatory neurotransmission throughout the GABA interneurons. In addition, Cotinine acting on the α7 nAChRs and TLR reduces neuroinflammation by inhibiting the release of pro-inflammatory cytokines by the immune cells. Also, α7nAChRs stimulate signaling pathways supporting structural, biochemical, electrochemical, and cellular changes in the Central nervous system during the cognitive processes, including Neurogenesis. Here, the mechanisms of memory formation as well as potential mechanisms of action of Cotinine on memory preservation in aging and neurological diseases are discussed.
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Affiliation(s)
- Valentina Echeverria
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Concepción, Chile
- Research and Development Department, Bay Pines VAHCS, Bay Pines, FL, United States
| | - Cristhian Mendoza
- Facultad de Odontologia y Ciencias de la Rehabilitacion, Universidad San Sebastián, Concepción, Chile
| | - Alex Iarkov
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Concepción, Chile
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2
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Photobiomodulation prevents PTSD-like memory impairments in rats. Mol Psychiatry 2021; 26:6666-6679. [PMID: 33859360 PMCID: PMC8760076 DOI: 10.1038/s41380-021-01088-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 03/17/2021] [Accepted: 03/29/2021] [Indexed: 02/02/2023]
Abstract
A precise fear memory encoding a traumatic event enables an individual to avoid danger and identify safety. An impaired fear memory (contextual amnesia), however, puts the individual at risk of developing posttraumatic stress disorder (PTSD) due to the inability to identify a safe context when encountering trauma-associated cues later in life. Although it is gaining attention that contextual amnesia is a critical etiologic factor for PTSD, there is no treatment currently available that can reverse contextual amnesia, and whether such treatment can prevent the development of PTSD is unknown. Here, we report that (I) a single dose of transcranial photobiomodulation (PBM) applied immediately after tone fear conditioning can reverse contextual amnesia. PBM treatment preserved an appropriately high level of contextual fear memory in rats revisiting the "dangerous" context, while control rats displayed memory impairment. (II) A single dose of PBM applied after memory recall can reduce contextual fear during both contextual and cued memory testing. (III) In a model of complex PTSD with repeated trauma, rats given early PBM interventions efficiently discriminated safety from danger during cued memory testing and, importantly, these rats did not develop PTSD-like symptoms and comorbidities. (IV) Finally, we report that fear extinction was facilitated when PBM was applied in the early intervention window of memory consolidation. Our results demonstrate that PBM treatment applied immediately after a traumatic event or its memory recall can protect contextual fear memory and prevent the development of PTSD-like psychopathological fear in rats.
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3
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Buckner CA, Buckner AL, Koren SA, Persinger MA, Lafrenie RM. The effects of electromagnetic fields on B16-BL6 cells are dependent on their spatial and temporal character. Bioelectromagnetics 2016; 38:165-174. [DOI: 10.1002/bem.22031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 12/07/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Carly A. Buckner
- Department of Biomolecular Sciences; Laurentian University; Sudbury Ontario Canada
- Regional Cancer Program; Sudbury Regional Hospital; Sudbury Ontario Canada
| | - Alison L. Buckner
- Department of Biomolecular Sciences; Laurentian University; Sudbury Ontario Canada
- Regional Cancer Program; Sudbury Regional Hospital; Sudbury Ontario Canada
| | - Stan A. Koren
- Department of Behavioural Neuroscience; Laurentian University; Sudbury Ontario Canada
| | - Michael A. Persinger
- Department of Biomolecular Sciences; Laurentian University; Sudbury Ontario Canada
- Department of Behavioural Neuroscience; Laurentian University; Sudbury Ontario Canada
| | - Robert M. Lafrenie
- Department of Biomolecular Sciences; Laurentian University; Sudbury Ontario Canada
- Regional Cancer Program; Sudbury Regional Hospital; Sudbury Ontario Canada
- Northern Ontario School of Medicine; Sudbury Ontario Canada
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4
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St-Pierre LS, Persinger MA. Conspicuous Histomorphological Anomalies in the Hippocampal Formation of Rats Exposed Prenatally to a Complex Sequenced Magnetic Field within the Nanotesla Range. Percept Mot Skills 2016; 97:1307-14. [PMID: 15002875 DOI: 10.2466/pms.2003.97.3f.1307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The brains of adult rats, exposed prenatally to one of four intensities (between 10 nanoTesla and 1.2 microTesla) of either a frequency-modulated magnetic field or a complex sequenced field designed to affect brain development, were examined histologically. Although from each intensity some rats that had been exposed to the complex sequenced magnetic field showed minor anomalies, those exposed to intensities between 30 nT and 180 nT exhibited conspicuous anomalous organizations of cells within the hippocampal formation. In other studies, rats that had been exposed during their entire prenatal development to the complex sequenced field displayed significantly more activity in the open field and poorer spatial memory during maze learning. Photomicrographs are shown of one conspicuous morphological anomaly within the right hippocampus of an adult rat exposed prenatally to the complex sequenced magnetic field with intensities between .3 mG and .5 mG (30 nT to 50 nT). The results suggest that complex magnetic fields, whose temporal structures approach the time constants of normal biochemical processes, can permanently alter the development of the brain.
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Paffi A, Camera F, Lucano E, Apollonio F, Liberti M. Time resolved dosimetry of human brain exposed to low frequency pulsed magnetic fields. Phys Med Biol 2016; 61:4452-65. [PMID: 27223143 DOI: 10.1088/0031-9155/61/12/4452] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
An accurate dosimetry is a key issue to understanding brain stimulation and related interaction mechanisms with neuronal tissues at the basis of the increasing amount of literature revealing the effects on human brain induced by low-level, low frequency pulsed magnetic fields (PMFs). Most literature on brain dosimetry estimates the maximum E field value reached inside the tissue without considering its time pattern or tissue dispersivity. Nevertheless a time-resolved dosimetry, accounting for dispersive tissues behavior, becomes necessary considering that the threshold for an effect onset may vary depending on the pulse waveform and that tissues may filter the applied stimulatory fields altering the predicted stimulatory waveform's size and shape. In this paper a time-resolved dosimetry has been applied on a realistic brain model exposed to the signal presented in Capone et al (2009 J. Neural Transm. 116 257-65), accounting for the broadband dispersivity of brain tissues up to several kHz, to accurately reconstruct electric field and current density waveforms inside different brain tissues. The results obtained by exposing the Duke's brain model to this PMF signal show that the E peak in the brain is considerably underestimated if a simple monochromatic dosimetry is carried out at the pulse repetition frequency of 75 Hz.
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Affiliation(s)
- Alessandra Paffi
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy
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Potential production of Hughlings Jackson's "parasitic consciousness" by physiologically-patterned weak transcerebral magnetic fields: QEEG and source localization. Epilepsy Behav 2013; 28:395-407. [PMID: 23872082 DOI: 10.1016/j.yebeh.2013.05.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/07/2013] [Accepted: 05/20/2013] [Indexed: 11/22/2022]
Abstract
Exotic experiences such as the sensing of another consciousness or the detachment of consciousness from the body are occasionally reported by individuals with partial seizures from a temporal lobe focus. The experiences display the characteristics of Hughlings Jackson's "parasitic consciousness". We have hypothesized that these experiences are encouraged by slight discrepancies in hemispheric activity that can be simulated by application of weak, physiologically-patterned magnetic fields across the cerebral hemispheres. Electroencephalographic and Low Resolution Electromagnetic Tomography (sLORETA) data revealed altered activity bands within specific regions within the cerebral cortices during these experiences. The clear changes in power of brain activity were discerned after consistent durations of exposure to specifically patterned weak magnetic fields. Millisecond range point durations were required. The technology may be useful to explore the subjective components associated with complex partial seizures.
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7
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Digitized quantitative electroencephalographic patterns applied as magnetic fields inhibit melanoma cell proliferation in culture. Neurosci Lett 2012; 523:131-4. [DOI: 10.1016/j.neulet.2012.06.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 06/18/2012] [Accepted: 06/22/2012] [Indexed: 11/24/2022]
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Hu JH, St-Pierre LS, Buckner CA, Lafrenie RM, Persinger MA. Growth of injected melanoma cells is suppressed by whole body exposure to specific spatial-temporal configurations of weak intensity magnetic fields. Int J Radiat Biol 2010; 86:79-88. [DOI: 10.3109/09553000903419932] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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TSANG ERICW, KOREN STANLEYA, PERSINGER MICHAELA. Specific Patterns of Weak (1 microTesla) Transcerebral Complex Magnetic Fields Differentially Affect Depression, Fatigue, and Confusion in Normal Volunteers. Electromagn Biol Med 2009; 28:365-73. [DOI: 10.3109/15368370903206630] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Tehranipou M, Kafaee M. Effects of Exposure to Extremely Low-Frequency Magnetic Field of 4 μT
Intensity on Spatial Memory and Learning in Mice. ACTA ACUST UNITED AC 2009. [DOI: 10.3923/jbs.2010.67.70] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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11
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Whissell PD, Tsang EW, Mulligan BP, Persinger MA. Prenatal Exposures to LTP-Patterned Magnetic Fields: Quantitative Effects on Specific Limbic Structures and Acquisition of Contextually Conditioned Fear. Int J Neurosci 2009; 119:1-14. [DOI: 10.1080/00207450802480283] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Martin LJ, Koren SA, Persinger MA. INFLUENCE OF A COMPLEX MAGNETIC FIELD APPLICATION IN RATS UPON THERMAL NOCICEPTIVE THRESHOLDS: THE IMPORTANCE OF POLARITY AND TIMING. Int J Neurosci 2009; 114:1259-76. [PMID: 15370185 DOI: 10.1080/00207450490475689] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The application of a weak (1 microTesla) complex magnetic field pattern with a relevant electrophysiological signature produced an analgesic response in rats to thermal stimuli when the pattern was presented once every 4 sec for 30 min through iron-core solenoids. In one experiment, the burst-firing pattern was presented once every 4 s for 30 min and restricted to the positive polarity, negative polarity or a bipolar equivalent. The strongest analgesia occurred when the burst-firing pattern was presented with positive polarity or as the typical bipolar signal. Administrations of the burst-firing pattern once per week for four consecutive weeks produced analgesia that was clearly evident during the first, third, and fourth weeks but not during the second week of treatment. A telephone sensor coil (that can be readily obtained from local electronic shops) was then used instead of the solenoids along with an audio (.wav) file to generate the magnetic field; the analgesia was still apparent. However, when the magnetic pattern was generated from a compact disc source the analgesia was not evoked. The current results suggest that these fields can be generated through simple commercial devices controlled by available computer software.
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Affiliation(s)
- L J Martin
- Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ontario, Canada
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13
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Martin LJ, Persinger MA. The Influence of Various Pharmacological Agents on the Analgesia Induced by an Applied Complex Magnetic Field Treatment: A Receptor System Potpourri. Electromagn Biol Med 2009. [DOI: 10.1080/15368370500205431] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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McKay BE, Persinger MA. COMPLEX MAGNETIC FIELDS ENABLE STATIC MAGNETIC FIELD CUE USE FOR RATS IN RADIAL MAZE TASKS. Int J Neurosci 2009; 115:625-48. [PMID: 15823929 DOI: 10.1080/00207450590523945] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Male Wistar rats were trained in an eight-arm radial maze task (two sessions per day, delayed-non-matching-to-sample) that included an intramaze static magnetic field "cue" (185 microT) specific to the entrance point of one of the arms. Rats were exposed daily for 60 min to a complex magnetic field waveform (theta-burst pattern, 200-500 nT), presented with several different interstimulus intervals (ISIs), either immediately following training sessions or immediately preceding testing sessions. Application of the theta-burst stimulus with a 4000 ms ISI significantly improved the rats' memory for the arm of the radial maze whose position was indicated by the presence of a static magnetic field cue. Reference memory errors were homogeneously distributed among all eight arms of the maze for sham-exposed rats, and among the other seven arms of the maze for complex magnetic field-treated rats. These results suggest that static magnetic field cues may be salient orienting cues even in a microenvironment such as a radial maze, but their use as a cue during maze learning in rats is dependent on whole-body application of a specific time-varying complex magnetic field.
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Affiliation(s)
- B E McKay
- Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ontario, Canada
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15
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St-Pierre LS, Persinger MA. Behavioral Changes in Adult Rats After Prenatal Exposures to Complex, Weak Magnetic Fields. Electromagn Biol Med 2009; 27:355-64. [DOI: 10.1080/15368370802493396] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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Delparte JJ, Persinger MA. BRIEF EXPOSURES TO THETA-BURST MAGNETIC FIELDS IMPAIR THE CONSOLIDATION OF FOOD-INDUCED CONDITIONED PLACE PREFERENCE. Int J Neurosci 2009; 117:295-9. [PMID: 17365115 DOI: 10.1080/00207450500535834] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Theta-burst magnetic fields (1 microT) designed to mimic electrical stimuli employed in vitro to affect long-term potentiation have been previously shown to impair the acquisition of conditioned fear. In the current study, the authors were interested in investigating whether similar magnetic fields could affect the consolidation of food-induced conditioned place preference. Fourteen male Wistar rats were exposed to a theta-burst magnetic field (1 s pulse of 5 trains of an LTP-evoking pattern) continuously or with either a 5 s or 10 s interstimulus interval for 15 min immediately following 6 daily conditioning trials (15 min/day) in a place preference apparatus. Testing demonstrated the durations in the food-paired chamber was significantly shorter for all of the magnetic field-exposed groups compared to the sham-exposed group (they remained for longer periods in the food-paired chamber, typical of normal rats). In addition, the group exposed continuously to the LTP-magnetic field (1-ms interstimulus duration) displayed the least time in the food-paired chamber. The treatments explained 80% of the variance in durations within the experimental setting. These results suggest that exposures to theta-burst magnetic fields elicit amnesic effects for contextual stimuli.
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Affiliation(s)
- J J Delparte
- Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ontario, Canada
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17
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Martin LJ, Koren SA, Persinger MA. Thermal Analgesic Effects from Weak, Complex Magnetic Fields: Critical Parameters. Electromagn Biol Med 2009. [DOI: 10.1080/15368370500205399] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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St-Pierre LS, Mazzuchin A, Persinger MA. Altered blood chemistry and hippocampal histomorphology in adult rats following prenatal exposure to physiologically-patterned, weak (50–500 nanoTesla range) magnetic fields. Int J Radiat Biol 2009; 84:325-35. [DOI: 10.1080/09553000801953300] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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19
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Mach QH, Persinger MA. Behavioral changes with brief exposures to weak magnetic fields patterned to stimulate long-term potentiation. Brain Res 2009; 1261:45-53. [PMID: 19210956 DOI: 10.1016/j.brainres.2009.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 01/01/2009] [Accepted: 01/05/2009] [Indexed: 10/21/2022]
Abstract
Brief whole body exposures of rats to weak (1 microT) complex magnetic fields whose patterns induce long term potential (LTP) when applied as electric current to hippocampal slices produced powerful behavioral changes. Rats exposed for 30 min before but not 30 min after hourly training sessions for spatial memory displayed impairments comparable to those elicited by complete electrode-induced saturation of hippocampal activity. Exposure to the same LTP-patterned magnetic fields after weaning during the induction of limbic seizures produced diminished learning of conditioned contextual fear during adulthood. However exposure to magnetic fields designed to simulate a "virtual" hippocampal state during acquisition of a timed inhibitory task (DRL) facilitated performance. These results show that physiologically-patterned magnetic fields can produce dramatic changes in behavior when they are applied during states associated with marked synaptic plasticity.
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Affiliation(s)
- Quoc Hao Mach
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
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20
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Lagace N, St-Pierre LS, Persinger M. Attenuation of epilepsy-induced brain damage in the temporal cortices of rats by exposure to LTP-patterned magnetic fields. Neurosci Lett 2009; 450:147-51. [DOI: 10.1016/j.neulet.2008.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/31/2008] [Accepted: 11/04/2008] [Indexed: 10/21/2022]
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21
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St-Pierre L, Parker G, Bubenik G, Persinger M. Enhanced mortality of rat pups following inductions of epileptic seizures after perinatal exposures to 5 nT, 7 Hz magnetic fields. Life Sci 2007; 81:1496-500. [DOI: 10.1016/j.lfs.2007.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2007] [Revised: 09/05/2007] [Accepted: 09/10/2007] [Indexed: 11/16/2022]
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22
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St-Pierre LS, Koren SA, Persinger MA. Ambulatory effects of brief exposures to magnetic fields changing orthogonally in space over time. Int J Neurosci 2007; 117:417-20. [PMID: 17365125 DOI: 10.1080/00207450600592214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In a within-subject design adult male rats were exposed for 15 min once per day or night to one of two patterns of complex magnetic fields (0.5 to 1 micro T) rotated in space once every 2 s or 20 s through each of the three spatial dimensions and then simultaneously through all three dimensions. Open field behavior was then measured for ambulation, defecation, and grooming. The rats displayed about twice the ambulation after when the fields had been present compared to when they had not. The burst-firing field elicited the greatest ambulation when presented during the night whereas the frequency-modulated pattern elicited the greatest ambulation when presented during the day. These results suggest that robust behavioral changes can occur when rats are exposed for 15 min to complex spatiotemporal configurations of weak magnetic fields.
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McKay BE, Persinger MA. Weak, physiologically patterned magnetic fields do not affect maze performance in normal rats, but disrupt seized rats normalized with ketamine: possible support for a neuromatrix concept? Epilepsy Behav 2006; 8:137-44. [PMID: 16388988 DOI: 10.1016/j.yebeh.2005.11.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Revised: 10/11/2005] [Accepted: 11/13/2005] [Indexed: 11/30/2022]
Abstract
The concept of a neuromatrix as a determinant of behavior proposes that complex neuroelectromagnetic patterns supported by specific spatial configurations of neurons underlie the generation of behaviors. When the pattern of neuronal connectivity is changed, as occurs during limbic epilepsy, neuroelectromagnetic patterns change in parallel to sustain behavioral output. Thus, a testable prediction of the neuromatrix concept is that the "normal" behaviors of animals with markedly reorganized neuroelectromagnetic patterns are vulnerable to specific stimuli that are ineffective when applied to a normal population. Because rats treated with ketamine after being induced to seize with pilocarpine exhibit behaviors indistinguishable from those of control populations despite marked changes in brain structure, they represent an ideal population in which to examine this hypothesis. Ketamine-treated pilocarpine-seized rats and normal rats were exposed continuously either to a complex sequence magnetic field or to control conditions during the acquisition of a radial arm maze task for 8 consecutive days. After 14 days of subsequent exposure to a frequency-modulated field (7-500 nT), during which time there was no training, the rats that had been induced to seize and had been exposed continuously to this magnetic configuration exhibited conspicuously slower response durations per arm than rats that had been induced to seize and exposed to control conditions or normal rats that had been exposed to either magnetic fields or control conditions. Thus, the behaviors of rats who have sustained multiple, discrete injuries throughout the brain may be seriously disrupted by the appropriate pattern of exogenous weak magnetic fields. Our results represent the first empirical support for the concept of the neuromatrix.
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Affiliation(s)
- B E McKay
- Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ont., Canada P3E 2C6
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24
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Fitzpatrick RE, Persinger MA. Weekly Treatments with a Burst-Firing Magnetic Field Alters Behavior in the Elevated plus Maze after Two Sessions. Percept Mot Skills 2004; 98:983-4. [PMID: 15209315 DOI: 10.2466/pms.98.3.983-984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In a split-litter design, rats were either injected with 15 mg/kg of clomipramine or saline from postnatal Days 8 through 21. Other rats from the same litters were not injected. When the rats were 90 days of age, the rats were tested once per week for five weeks in an elevated plus maze that contained two open arms (no walls) and two walled arms. Following each test, they were exposed (total of 4 exposures) for 30 min. to a burst-firing magnetic field (1 microTesla) that has been shown to reduce depression in human beings. After two treatments, the rats exposed to the burst-firing fields spent about half the amount of time in the open arms compared to the sham-field exposed rats. The interaction between adult treatment and whether the rats had received the antidepressant before weaning was not significant statistically. These results suggest that at least two weekly sessions may be required before significant changes in behavior occur after weekly 30-min. exposures to these potentially “therapeutic” magnetic fields.
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25
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Martin LJ, Koren SA, Persinger MA. Thermal analgesic effects from weak, complex magnetic fields and pharmacological interactions. Pharmacol Biochem Behav 2004; 78:217-27. [PMID: 15219761 DOI: 10.1016/j.pbb.2004.03.016] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2003] [Revised: 03/09/2004] [Accepted: 03/13/2004] [Indexed: 11/22/2022]
Abstract
In several experiments, robust analgesia (equivalent to about 4 mg/kg of morphine) in male rats to thermal stimuli following exposures to weak (1 microT) complex magnetic fields was explored. The analgesia occurred when patterns of magnetic fields with burst-firing-like configurations were presented for 30 min once every approximately 4 s. The analgesic effects were intensity dependent. A different frequency-modulated pattern produced analgesia more quickly. The analgesic effects following exposure to the burst-firing magnetic fields were augmented conspicuously by preinjections of morphine (4 mg/kg) or agmatine (10 mg/kg), but blocked by naloxone (1 mg/kg). The results of these experiments suggest that rational design of the temporal structure of weak magnetic fields may be a novel, inexpensive, and reliable technique for elevating thresholds to some classes of painful stimuli.
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Affiliation(s)
- L J Martin
- Behavioral Neuroscience Program, Behavioral Neuroscience Laboratory, Department of Biology, Laurentian University, Sudbury, Ontario, Canada P3E 2C6
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26
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McKay BE, Persinger MA. Conditioned taste aversion is not disrupted in rats exposed to weak, complex magnetic fields during the CS-UCS interval. Percept Mot Skills 2004; 97:1335-8. [PMID: 15002878 DOI: 10.2466/pms.2003.97.3f.1335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
40 normal male Wistar rats were trained for 8 successive days to consume water ad libitum during once-daily 20-min. sessions. On the following day (training day) the rats were presented with a novel solution of 10% sucrose for 20 min. followed by a single exposure for 2 hr. to one of two weak (200 to 500 nanoTesla) complex magnetic fields or to sham-field conditions. The patterns of the two magnetic fields and the durations of their repeated presentations (interstimulus interval) were designed to be resonant with the intrinsic firing of hippocampal pyramidal and solitary neurons, respectively. Immediately after the applications of the fields one-half the number of rats were injected with lithium to evoke gastrointestinal malaise. Although on the test day, three days later, rats previously injected with the lithium exhibited the usual robust reduction in the consumption of sucrose compared to the training day, there were no statistically significant differences between field-exposed and sham-field groups for these ratios. We conclude that a 2-hr. exposure to weak magnetic fields designed to simulate the pattern of two structures likely involved with conditioned taste aversion between the conditioned stimulus and the unconditioned stimulus did not affect this behavior.
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Affiliation(s)
- B E McKay
- Laurentian University, Sudbury, Ontario, Canada
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Martin LJ, Persinger MA. Spatial heterogeneity not homogeneity of the magnetic field during exposures to complex frequency-modulated patterns facilitates analgesia. Percept Mot Skills 2003; 96:1005-12. [PMID: 12831282 DOI: 10.2466/pms.2003.96.3.1005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
24 young (4 mo.) and 24 old (8 mo.) male Wistar rats were exposed for 30 min. on two consecutive days to either a sham-field or to a frequency-modulated magnetic field applied through a pair of solenoids (spatially heterogeneous strength) or a Helmholtz coil (spatially homogeneous strength). The maximum field strength was about 2 microTesla. The rats exposed to the spatially heterogeneous magnetic field but not the homogeneous magnetic field exhibited strong analgesia to thermal stimuli applied to the footpads immediately after the treatment and 30 min. later. The effect accommodated 38% of the variance in the latency to respond to the thermal stimuli. These results suggest that the practice by many researchers in bioelectromagnetism to design coils to generate maximum spatial homogeneity of intensities within the exposure volume when applying complex weak magnetic fields may actually diminish any biological effects.
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Affiliation(s)
- L J Martin
- Laurentian University, Sudbury, ON Canada
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McKay BE, Persinger MA. Combined effects of complex magnetic fields and agmatine for contextual fear learning deficits in rats. Life Sci 2003; 72:2489-98. [PMID: 12650857 DOI: 10.1016/s0024-3205(03)00140-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Acute post-training exposures to weak intensity theta-burst stimulation (TBS) patterned complex magnetic fields attenuated the magnitude of conditioned fear learning for contextual stimuli. A similar learning impairment was evoked in a linear and dose-dependent manner by pre-conditioning injections of the polyamine agmatine. The present study examined the hypothesis that whole-body applications of the TBS complex magnetic field pattern when co-administered with systemic agmatine treatment may combine to evoke impairments in contextual fear learning. Within minutes of 4 mg/kg agmatine injections, male Wistar rats were fear conditioned to contextual stimuli and immediately exposed for 30 min to the TBS patterned complex magnetic field or to sham conditions. TBS patterned complex magnetic field treatment was found to linearly summate with the contextual fear learning impairment evoked by agmatine treatment alone. Furthermore, we report for sham-treated rats, but not rats exposed to the synthetic magnetic field pattern, that the magnitude of learned fear decreased and the amount of variability in learning increased, as the K-index (a measure of change in intensity of the time-varying ambient geomagnetic field) increased during the 3-hr intervals over which conditioning and testing sessions were conducted.
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Affiliation(s)
- B E McKay
- Behavioral Neuroscience Laboratory, Laurentian University, Ontario, P3E 2C6, Sudbury, Canada.
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McKay BE, St-Pierre LS, Persinger MA. Radial maze proficiency of adult Wistar rats given prenatal complex magnetic field treatments. Dev Psychobiol 2003; 42:1-8. [PMID: 12471631 DOI: 10.1002/dev.10072] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Exposure to sinusoidal (power-frequency) magnetic fields during prenatal development is implicated in adulthood behavioral impairments. However, the effects of prenatal exposure to weak-intensity, nonsinusoidal complex magnetic fields (CMFs), an increasingly common feature of the modern environment, have not been rigorously examined. In the present study, male and female Wistar-strain rats were exposed continually during prenatal development to one of three extremely low-frequency CMFs or a sham condition. As adults, rats were trained in an acquisition/reversal radial maze task. All rats exposed to the prenatal CMFs increased their commission of reference memory errors, but differences in working memory and motivation to complete the maze task were specific to the type of prenatal CMF. These results provide the first evidence that prenatal exposures to specific shapes of CMFs impair complex learning behaviors into adulthood.
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Affiliation(s)
- B E McKay
- Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ontario, Canada, P3E 2C6
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Abstract
Despite intensive investigation into the mechanisms underlying the memory process, the physical bases for this superior cognitive function remain elusive. Recall of past events and actions depends on the generation of complex memory carriers that would have to integrate many items of information. Some human memory processes, like contextual recall, work at such high speed and integrate such a large number of cortical neurons and neuronal networks that molecular mechanisms of information storage and synaptic transmission seem insufficient. This limitation argues against molecular information storage mechanisms as being truly effective carriers for the memory process. In this paper, I propose that any type of information can be stored in the form of 'neuronal activity-associated magnetic fields' that would record information in much the same way as the magnetic tape of a tape recorder. Integration and/or combination of the neuronal activity-associated magnetic fields throughout the complex three-dimensional structure of the human cortex could provide a storage medium for high-speed processing and discrimination that would support the complexity of the human memory process.
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Affiliation(s)
- M A M Banaclocha
- Department of Pathology, Hospital General de Castellón, Castellón, Spain.
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Richards MA, Koren SA, Persinger MA. Circumcerebral application of weak complex magnetic fields with derivatives and changes in electroencephalographic power spectra within the theta range: implications for states of consciousness. Percept Mot Skills 2002; 95:671-86. [PMID: 12434867 DOI: 10.2466/pms.2002.95.2.671] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Relative power within the delta, theta, low-alpha, high-alpha, and gamma electroencephalographic spectra of 8 human volunteers was recorded over the left and right frontal, temporal, parietal, and occipital lobes during and after the circumcerebral application through an array of 8 solenoids of 6 different configurations of weak (5 to 10 microTesla) magnetic fields. The solenoids were equally spaced around the subject's head along a horizontal plane above the ears. An approximately 30% increase in power within the theta band occurred transcerebrally during the application of a specific configuration, previously shown to affect subjective time, involving 20-msec. rates of change in the duration of delivery of the magnetic fields to each successive solenoid. Compared to the left hemisphere, the right hemisphere displayed a 20% increase in power within the 5.0- to 5.9-Hz range for all 6 configurations. The results suggest that very complex magnetic fields with the appropriate temporal parameters rotated around and within brain space can interact with the cerebral processes, measured as specific hands of frequencies, generating consciousness. Implications for the roles of hippocampal theta activity, cortical resonance, and Goldstone bosons in these processes are discussed.
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Affiliation(s)
- M A Richards
- Department of Psychology, Laurentian University, Sudbury, ON, Canada
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Ryczko MC, Persinger MA. Increased analgesia to thermal stimuli in rats after brief exposures to complex pulsed 1 microTesla magnetic fields. Percept Mot Skills 2002; 95:592-8. [PMID: 12434855 DOI: 10.2466/pms.2002.95.2.592] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Nociceptive thresholds to a 55 degrees C hot surface were measured for female Wistar rats before treatments and 30 min. and 60 min. after the treatments. After injection with either naloxone or saline following baseline measurements, the rats were exposed for 30 min. to either sham fields or to weak (about 1 microTesla) burst-firing magnetic fields composed of 230 points (4 msec. per point) presented once every 3 sec. The rats that had received the burst-firing magnetic fields exhibited elevated nociceptive thresholds that explained about 50% of the variance. A second pattern, designed after the behaviour of individual thalamic neurons during nociceptive input and called the "activity rhythm magnetic field" produced only a transient analgesic effect. These results replicated previous studies and suggest that weak, extremely low frequency, pulsed magnetic fields with biorelevant temporal structures may have utility as adjuncts for treatment of pain.
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Affiliation(s)
- M C Ryczko
- Behavioral Neuroscience Program, Laurentian University, Sudbury, ON, Canada
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Persinger MA, Healey F. Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields. J Nerv Ment Dis 2002; 190:533-41. [PMID: 12193838 DOI: 10.1097/00005053-200208000-00006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
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.
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Affiliation(s)
- Michael A Persinger
- Behavioral Neuroscience Program, Department of Psychology, Laurentian University, Sudbury, Ontario P3E 2C6
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Persinger MA. Geophysical variables and behavior: XCVIII. Ambient geomagnetic activity and experiences of "memories": interactions with sex and implications for receptive psi experiences. Percept Mot Skills 2002; 94:1271-82. [PMID: 12186249 DOI: 10.2466/pms.2002.94.3c.1271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
During 96 nonsequential days over a 3-yr. period, a total of 53 men and 86 women were exposed only once for 30 min. to transcerebral, weak complex magnetic fields while they sat alone within a quiet chamber. They were asked to record the frequency of specific experiences after the exposure was completed. There was a significant interaction between sex and global geomagnetic activity for the incidence of experiences attributed to memories. Women reported more experiences attributed to "childhood memories" when geomagnetic activity was less than 20 nT, while men reported more of these experiences when the activity was more than 20 nT. Re-analyses of a database of "paranormal experiences" reported by 395 separate individuals over a 100-yr. period indicated that more men than women reported "precognitive experiences" on days the geomagnetic activity was above 20 nT while women reported such experiences if the geomagnetic activity was below 20 nT. These results suggest that these experiences, be they veridical or illusory, may be influenced by global geomagnetic activity that affect the neuroelectrical or neurochemical processes associated with memory consolidation or the attribution of the serial order of experiences during retrieval.
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Affiliation(s)
- M A Persinger
- Department of Psychology, Laurentian University, Sudbury, Ontario, Canada
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Roll WG, Persinger MA, Webster DL, Tiller SG, Cook CM. Neurobehavioral and neurometabolic (SPECT) correlates of paranormal information: involvement of the right hemisphere and its sensitivity to weak complex magnetic fields. Int J Neurosci 2002; 112:197-224. [PMID: 12325407 DOI: 10.1080/00207450212025] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Experiments were designed to help elucidate the neurophysiological correlates for the experiences reported by Sean Harribance. For most of his life he has routinely experienced "flashes of images" of objects that were hidden and of accurate personal information concerning people with whom he was not familiar. The specificity of details for target pictures of people was correlated positively with the proportion of occipital alpha activity. Results from a complete neuropsychological assessment, Single Photon Emission Computed Tomography (SPECT), and screening electroencephalography suggested that his experiences were associated with increased activity within the parietal lobe and occipital regions of the right hemisphere. Sensed presences (subjectively localized to his left side) were evoked when weak, magnetic fields, whose temporal structure simulated long-term potentiation in the hippocampus, were applied over his right temporoparietal lobes. These results suggest that the phenomena attributed to paranormal or "extrasensory" processes are correlated quantitatively with morphological and functional anomalies involving the right parietotemporal cortices (or its thalamic inputs) and the hippocampal formation.
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Affiliation(s)
- W G Roll
- State University of West Georgia, Carrollton, Georgia, USA
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RYCZKO MC. INCREASED ANALGESIA TO THERMAL STIMULI IN RATS AFTER BRIEF EXPOSURES TO COMPLEX PULSED MICROTESLA MAGNETIC FIELDS. Percept Mot Skills 2002. [DOI: 10.2466/pms.95.6.592-598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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PERSINGER MA. GEOPHYSICAL VARIABLES AND BEHAVIOR: XCVIII. AMBIENT GEOMAGNETIC ACTIVITY AND EXPERIENCES OF 'MEMORIES': INTERACTIONS WITH SEX AND IMPLICATIONS FOR RECEPTIVE PSI EXPERIENCES. Percept Mot Skills 2002. [DOI: 10.2466/pms.94.2.1271-1282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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38
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PERSINGER MA. GEOPHYSICAL VARIABLES AND BEHAVIOR: XCVIII. AMBIENT GEOMAGNETIC ACTIVITY AND EXPERIENCES OF 'MEMORIES': INTERACTIONS WITH SEX AND IMPLICATIONS FOR RECEPTIVE PSI EXPERIENCES. Percept Mot Skills 2002. [DOI: 10.2466/pms.94.3.1271-1282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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