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Biomedical subjects

M A Persinger

Publications and source records attributed to M A Persinger.

At least 145 records · Page 8Linked to original sources

Experimental induction of the "sensed presence" in normal subjects and an exceptional subject.

9 of the 15 volunteers who were exposed to successive 3-min. durations of bursts of different types of weak (1 microT) complex magnetic fields or sham-fields reported the sense of a presence as indicated by a button press at the time of the experience. Reports of subjective experiences indicated that attempts to "focus" cognitively upon the location of the presence altered its location or induced its "movement." An exceptional subject who had a history of experiencing within his upper left peripheral visual field "flashing images" concerning the health and history of people [when handling their photographs] was also exposed to the burst sequences. Numbers of button presses associated with the experiences of a mystical presence, to whom the subject attributed his capacity, increased when the complex magnetic fields were applied without the subject's knowledge. The results support the hypothesis that the sense of a presence, which may be the common phenomenological base from which experiences of gods, spirits, angels, and other entities are derived, is a right hemispheric homologue of the left hemispheric sense of self.

Adult↗

Geomagnetic variables and behavior: LXXXIII. Increased geomagnetic activity and group aggression in chronic limbic epileptic male rats.

PX / PPseparate experiments the daily intragroup aggression was IC SYSTEM / * PPo different measures for male rats with limbic epilepsy ESSION / * PXre were statistically positive associations of moderate strength (rs about .50) for the frequency with severity of intermale aggression and daily geomagnetic activity. The intense aggression was most evident when the daily aa values for the northern hemisphere, one measure of daily global geomagnetic activity, exceeded 40 nT. Implications for homologous behaviors for human beings, as a species, are suggested.

Aggression↗

Control of "choice" by application of the electromagnetic field equivalents of spoken words: mediation by emotional meaning rather than linguistic dimensions?

Electromagnetic equivalents (about 1 microT) of the acoustic signature of spoken words were applied across the temporoparietal lobes by an array of external solenoids. Participants were asked to select the target word within a group of words. The experimental group of 7 chose the target word or words that shared its emotional dimensions (activation, evaluation) more frequently than did the reference group of 6 who received no electromagnetic equivalents. Implications for the neurocognitive detection of the emotional (connotative) components of word stimuli when transformed to electromagnetic equivalents rather than direct images or "word sounds" are discussed.

Acoustic Stimulation↗

Effect of enhanced geomagnetic activity on hypothermia and mortality in rats.

The hypothesis was investigated that variability in the severity of limbic seizure-induced hypothermia in rats was affected by ambient geomagnetic activity. Data were obtained in support of this hypothesis. The depth of the hypothermia was significantly (P < 0.001) reduced if the ambient geomagnetic activity exceeded 35 nT to 40 nT. Mortality during the subsequent 5 days was increased when the geomagnetic activity was > 20 nT. The magnitude of the effect was comparable to the difference between exposure to light or to darkness during the 20 h after the induction of limbic seizures.

Animals↗

Visuospatial/vocabulary differences in boys and girls and a potential age-dependent drift in vocabulary proficiency.

A total of 188 monolingual (English) boys and girls whose ages ranged from 6 years through 14 years were administered the Vocabulary and Block Design subtests of the Wechsler Intelligence Scale for Children. Although the boys (n = 85) displayed significantly greater relative strengths for the visuospatial task than the girls (n = 103), the effect was due primarily to the boys' less proficient Vocabulary scores. The detection of a significant linear decrease (r = -.32) in standardized scores for Vocabulary but not for Block Design over this age span was not expected. The drift over 9 grades was equivalent to more than one standard deviation. Possible sources of interference such as exposure to the same second language that occupied 6% to 12% of the instructional time are suggested.

Adolescent↗

Attempts to simulate the association between geomagnetic activity and spontaneous seizures in rats using experimentally generated magnetic fields.

In three separate experiments, chronic epileptic male rats (ns = 24, 24, and 4) were exposed to experimental magnetic fields whose intensities were either constant or varied. The ripple frequency was always 7 Hz. Only exposure to a field with a constant intensity (700 nT) appeared to inhibit occurrence of the seizures. Although exposure to a field configuration whose strength increased and decreased by fixed increments during the hour before feeding did not affect the incidence of seizures, exposure to these fields for 5 min, only once per hour (increments of 15 to 20 nT for 30 sec. to a maximum of 70 nT) during the previous night between midnight and 0800 hr. increased the proportion of seizures following the presentation of food. An explanation is given for the persistent antithetical effects of experimental magnetic fields and geomagnetic activity upon seizure phenomena.

Amygdala↗

Repeated verbal interruptions during exposure to complex transcerebral magnetic fields elicit irritability: implications for opiate effects.

Men (n = 17) and women (n = 18) listened to a brief narrative and then were exposed for 30 min. to a control condition or to a weak (1 microTesla) complex magnetic field applied over the left hemisphere, the right hemisphere, or bilaterally. The subjects were interrupted intermittently to report their thoughts during this period. Because the wave structure of the field had been shown to elevate nociceptive thresholds and to simulate the effects of morphine in rats, we predicted that the group who received the bilateral stimulation should report greater irritability because of their disrupted pleasant experiences. The results supported this hypothesis.

Adult↗

Geophysical variables and behavior: LXXX. Periodicities and energetic characteristics of a strobe-light luminosity during a geomagnetic storm.

A videotape of a "strobe-light" luminosity that occurred in northern Ontario for several minutes during the evening of 6 October, 1994, at the time of a geomagnetic storm, was analyzed frame by frame. Brightness of the flashes decreased over the time of the observation. The interflicker intervals displayed phase-shifted periodicities that would be compatible with a rotating electromagnetic dipole and with the observations of the witnesses. The time of the occurrence and the dynamics of the luminosity were consistent with the predictions of the tectonic strain hypothesis.

Electromagnetic Fields↗

Demands during maze. learning in limbic epileptic rats: selective damage in the thalamus?

A qualitatively evident enhancement of chromolytic neurons within the lateral posterior thalamus of rats in which limbic seizures had been induced by lithium and pilocarpine and who were later trained for spatial memory was assessed quantitatively. The significant increase in the numbers of chromolytic neurons and the decrease in the numbers of normal neurons for these rats compared to the reference brains suggested these morphological changes were recent. The hypothesis that excessive stimulation of the lateral posterior nucleus by daily training in a radial maze may have facilitated the necrosis was supported by the inverse relationship between a linear combination of the numbers of normal neurons and oligodendroglia and the rate of learning during the earlier but not the later sessions. An implication for iatrogenic effects from rehabilitation of humans following brain injury was suggested.

Animals↗

Weak, but complex pulsed magnetic fields may reduce depression following traumatic brain injury.

Many patients who display psychological depression following a traumatic brain injury do not respond completely to antidepressant drugs. We hypothesized that this type of depression is strongly correlated with subclinical, complex partial seizure-activity within the hippocampal-amygdaloid region that continues for months to years after apparent neurological and behavioral "recovery." Four depressed patients who had sustained traumatic brain injuries and who exhibited mild to moderate brain impairment according to standardized tests received 30 min. of weak (1 microT) burst-firing magnetic fields across the temporal lobes once per week for 5 weeks. There was a significant improvement of depression and reduction of phobias while physical symptoms and other complaints were not changed.

Adult↗

Long-term consequences of subtle stimuli during the first twenty-four hours of seizure-induced brain injury.

Chronically epileptic (induced by a single systemic injection of lithium and pilocarpine about 30 days before the experiment began) male rats were trained within a radial maze while they were administered either GABA-pentin (Neurontin), or prednisolone or given no treatment. There was no significant improvement in learning or memory between the groups. Numbers of trials per day were positively correlated with the time required to display the overt stereotyped forelimb clonus after the single pilocarpine injection. The numbers of correct trials completed during the first few days of acquisition were significantly greater for the rats that had receive weak (1 microT) complex, pulsed magnetic fields over the right hemisphere during the first 24 hr. after seizure induction than for those who received the same field over the left hemisphere or that had been exposed to reference conditions. Implications of the enhanced sensitivity of limbic neurons to subtle electromagnetic interaction during electrical lability are discussed.

Acetates↗

Feelings of past lives as expected perturbations within the neurocognitive processes that generate the sense of self: contributions from limbic lability and vectorial hemisphericity.

Normal, young men and women who believed they may have lived a previous life (n = 21) or who did not endorse (n = 52) this belief of "reincarnation" were exposed to partial sensory deprivation and received transcerebral stimulation by burst-firing magnetic fields over either the left or right hemisphere. Individuals who reported belief in reincarnation could be discriminated from nonbelievers by their more frequent report of experiences of tingling sensations, spinning, detachment of consciousness from the body, and intrusions of thoughts that were not attributed to the sense of self. The results support the hypothesis that there may be neurocognitive processes which identify experiences as originating from the sense of self (episodic or autobiographical memory) or "not self." When anomalous experiences are beyond the boundary of the experiences contained with the generalization gradient of concurrent autobiographical memory, they are more likely to be attributed to culturally available default explanations such as living a previous life.

Adult↗

Enhancement of limbic seizures by nocturnal application of experimental magnetic fields that simulate the magnitude and morphology of increases in geomagnetic activity.

Over a 200 day period, chronic (limbic) epileptic rats were exposed intermittently, for either one or three nights (00 to 08 hr), once very approximately 10 days to experimental magnetic fields whose morphology (incremental changes in intensity over time) simulated geomagnetic activity. One of two intensities and two ripple frequencies (7 Hz, 45 Hz) was employed. The display of over seizures following synchronized food presentation significantly increased by a factor 3.1 relative to controls when the fields had been activated for one or two but not three successive nights. The combined effects of the experimental field and ambient geomagnetic activity (> 40 nT) explained approximately 12 to 15% of the variance in the daily incidence of seizures. Implications for the transient disinhibition of electrical lability within the limbic system following suppression of nocturnal melatonin are discussed.

Animals↗

Increases in geomagnetic activity are associated with increases in thyroxine levels in a single patient: implications for melatonin levels.

Blood levels of free T4 (thyroxine), cortisol and prolactin over 19 successive days from a single limbic epileptic patient were correlated with daily geomagnetic activity (aa values) for the northern hemisphere. Only thyroxine levels were correlated (r = 0.66) significantly with the daily geomagnetic activity; the strongest association (rho = 0.76) occurred between thyroxine levels and the geomagnetic activity (Kp values) during the previous night (2:00 A.M. to 5:00 A.M. local time). These results support the hypothesis that suppression of (nocturnal) melatonin levels by increased geomagnetic activity attenuates the tonic inhibition by this pineal compound upon thyroidal metabolism.

Adult↗

Enhanced hypnotic suggestibility following application of burst-firing magnetic fields over the right temporoparietal lobes: a replication.

The suggestibility of normal, young men and women as assessed by Spiegel's Hypnosis Induction Profile (HIP) before and after weak (1 micro Tesla), burst-firing magnetic fields were applied for 20 min over the left or over the right temporoparietal lobe or both hemispheres; a fourth group received sham treatment. Only the group that received the stimulation over the right hemisphere exhibited a marked increase in suggestibility (eta = 0.58) following the treatment. These results replicate components of several different previous experiments and suggest that attribution of symptomatic changes following exposures to weak, extremely low frequency magnetic fields, to placebo effects may not be correct. Instead, fields whose signatures contain biorelevant information may directly affect the neurocognitive processes that are associated with hypnotizability.

Adult↗

Vestibular experiences of humans during brief periods of partial sensory deprivation are enhanced when daily geomagnetic activity exceeds 15-20 nT.

The intensity of reported vestibular experiences by normal volunteers (n = 127, over a 4-year period) increased significantly in a step-like manner during partial sensory deprivation when the daily geomagnetic activity exceeded about 15 nT; the effect size was equivalent to a correlation of about 0.33. Post hoc analyses indicated that the geomagnetic activity during the 3-h period at the beginning of the previous sleep cycle was the single greatest contributor. The enhanced occurrences of experiences that are similar to those associated with complex partial epileptic seizures suggests that specific stimuli associated with geomagnetic activity above about 15 nT affects specific regions of the human brain; the vulnerability occurs during the subsequent 24 h. However, in non-epileptic individuals these experiences must be amplified neurocognitively by removing input from auditory and visual modalities.

Adolescent↗

Decreased latencies for limbic seizures induced in rats by lithium-pilocarpine occur when daily average geomagnetic activity exceeds 20 nanoTesla.

A decrease in the latency for the overt display of limbic seizures following the systemic injection of lithium and pilocarpine is weakly associated with enhanced global geomagnetic activity (in nanoTesla; nT). To determine the optimal threshold in global geomagnetic activity that is required for this effect, the seizure onset times for over 300 rats were dichotomized according to successive 5 nT increments. The results suggested that the seizure process occurred about 12% more quickly when the average daily global geomagnetic activity exceeded 20-25 nT and is commensurate with the observations by other researchers.

Animals↗

Sudden unexpected death in epileptics following sudden, intense, increases in geomagnetic activity: prevalence of effect and potential mechanisms.

Abrupt, intense increases in global geomagnetic activity during the local night may precipitate a significant proportion of sudden unexpected (or unexplained) deaths (SUD) in epileptics. Over a 2-year period SUD in healthy chronic epileptic rats occurred when the average daily geomagnetic activity exceeded 50 nT (nanoTesla) and suddenly began during local night. Other experiments demonstrated that epileptic rats displayed more spontaneous seizures per night if there had been sudden increases in geomagnetic activity. Analyses of previously published data indicated that the number of SUDs/month in a population of human epileptics was positively associated with the number of days/month when the average geomagnetic activity exceeded 50 nT. The results support the hypothesis that suppression of the nocturnal concentrations of the endogenous anticonvulsant melatonin by sudden increases in geomagnetic activity may encourage fatal cardiac arrhythmias by uncoupling the insular/amygdaloid-paraventricular hypothalamic-solitary nucleus pathways.

Animals↗