Experimental Simulation of a Haunt Experience and Elicitation of Paroxysmal Electroencephalographic Activity by Transcerebral Complex Magnetic Fields: Induction of a Synthetic “Ghost”?

2000 ◽  
Vol 90 (2) ◽  
pp. 659-674 ◽  
Author(s):  
M. A. Persinger ◽  
S. G. Tiller ◽  
S. A. Koren

To test the hypothesis that experiences of apparitional phenomena with accompanying fear can be simulated within the laboratory, a 45-yr.-old Journalist and professional musician who had experienced a classic haunt four years previously was exposed to 1 microTesla, complex, transcerebral magnetic fields. Within 10 min. after exposure to a frequency-modulated pattern applied over the right hemisphere, the man reported “rushes of fear” that culminated in the experience of an apparition. Concurrent electroencephalographic measurements showed conspicuous 1-sec-to-2-sec. paroxysmal complex spikes (15 Hz) that accompanied the reports of fear. A second magnetic field pattern, applied bilaterally through the brain, was associated with pleasant experiences. The subject concluded that the synthetic experience of the apparition was very similar to the one experienced in the natural setting. The results of this experiment suggest that controlled simulation of these pervasive phenomena within the laboratory is possible and that this experimental protocol may help discern the physical stimuli that evoke their occurrence in nature.

2020 ◽  
Author(s):  
Elmira Zaynagutdinova ◽  
Karina Karenina ◽  
Andrey Giljov

Abstract Behavioural lateralization, which reflects the functional specializations of the two brain hemispheres, is assumed to play an important role in cooperative intraspecific interactions. However, there are few studies focused on the lateralization in cooperative behaviours of individuals, especially in a natural setting. In the present study, we investigated lateralized spatial interactions between the partners in life-long monogamous pairs. The male-female pairs of two geese species (barnacle, Branta leucopsis, and white-fronted, Anser albifrons geese), were observed during different stages of the annual cycle in a variety of conditions. In geese flocks, we recorded which visual hemifield (left/right) the following partner used to monitor the leading partner relevant to the type of behaviour and the disturbance factors. In a significant majority of pairs, the following bird viewed the leading partner with the left eye during routine behaviours such as resting and feeding in undisturbed conditions. This behavioural lateralization, implicating the right hemisphere processing, was consistent across the different aggregation sites and years of the study. In contrast, no significant bias was found in a variety of geese behaviours associated with enhanced disturbance (when alert on water, flying or fleeing away when disturbed, feeding during the hunting period, in urban area feeding and during moulting). We hypothesize that the increased demands for right hemisphere processing to deal with stressful and emergency situations may interfere with the manifestation of lateralization in social interactions.


Author(s):  
Elizabeth Schechter

The largest fibre tract in the human brain connects the two cerebral hemispheres. A ‘split-brain’ surgery severs this structure, sometimes together with other white matter tracts connecting the right hemisphere and the left. Split-brain surgeries have long been performed on non-human animals for experimental purposes, but a number of these surgeries were also performed on adult human beings in the second half of the twentieth century, as a medical treatment for severe cases of epilepsy. A number of these people afterwards agreed to participate in ongoing research into the psychobehavioural consequences of the procedure. These experiments have helped to show that the corpus callosum is a significant source of interhemispheric interaction and information exchange in the ‘neurotypical’ brain. After split-brain surgery, the two hemispheres operate unusually independently of each other in the realm of perception, cognition, and the control of action. For instance, each hemisphere receives visual information directly from the opposite (‘contralateral’) side of space, the right hemisphere from the left visual field and the left hemisphere from the right visual field. This is true of the normal (‘neurotypical’) brain too, but in the neurotypical case interhemispheric tracts allow either hemisphere to gain access to the information that the other has received. In a split-brain subject however the information more or less stays put in whatever hemisphere initially received it. And it isn’t just visual information that is confined to one hemisphere or the other after the surgery. Rather, after split-brain surgery, each hemisphere is the source of proprietary perceptual information of various kinds, and is also the source of proprietary memories, intentions, and aptitudes. Various notions of psychological unity or integration have always been central to notions of mind, personhood, and the self. Although split-brain surgery does not prevent interhemispheric interaction or exchange, it naturally alters and impedes it. So does the split-brain subject as a whole nonetheless remain a unitary psychological being? Or could there now be two such psychological beings within one human animal – sharing one body, one face, one voice? Prominent neuropsychologists working with the subjects have often appeared to argue or assume that a split-brain subject has a divided or disunified consciousness and even two minds. Although a number of philosophers agree, the majority seem to have resisted these conscious and mental ‘duality claims’, defending alternative interpretations of the split-brain experimental results. The sources of resistance are diverse, including everything from a commitment to the necessary unity of consciousness, to recognition of those psychological processes that remain interhemispherically integrated, to concerns about what the moral and legal consequences would be of recognizing multiple psychological beings in one body. On the other hand underlying most of these arguments against the various ‘duality’ claims is the simple fact that the split-brain subject does not appear to be two persons, but one – and there are powerful conceptual, social, and moral connections between being a unitary person on the one hand and having a unified consciousness and mind on the other.


1997 ◽  
Vol 24 (3) ◽  
pp. 329-332 ◽  
Author(s):  
M HAJEK ◽  
C BOEHLE ◽  
R HUONKER ◽  
H VOLZ ◽  
H NOWAK ◽  
...  

1996 ◽  
Vol 82 (2) ◽  
pp. 639-642 ◽  
Author(s):  
Jason Freeman ◽  
M. A. Persinger

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.


Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 740 ◽  
Author(s):  
Charlotte Griffiths ◽  
Richard Holland ◽  
Anna Gagliardo

Functional lateralisation in the avian visual system can be easily studied by testing monocularly occluded birds. The sun compass is a critical source of navigational information in birds, but studies of visual asymmetry have focussed on cues in a laboratory rather than a natural setting. We investigate functional lateralisation of sun compass use in the visual system of homing pigeons trained to locate food in an outdoor octagonal arena, with a coloured beacon in each sector and a view of the sun. The arena was rotated to introduce a cue conflict, and the experimental groups, a binocular treatment and two monocular treatments, were tested for their directional choice. We found no significant difference in test orientation between the treatments, with all groups showing evidence of both sun compass and beacon use, suggesting no complete functional lateralisation of sun compass use within the visual system. However, reduced directional consistency of binocular vs. monocular birds may reveal a conflict between the two hemispheres in a cue conflict condition. Birds using the right hemisphere were more likely to choose the intermediate sector between the training sector and the shifted training beacon, suggesting a possible asymmetry in favour of the left eye/right hemisphere (LE/RH) when integrating different cues.


1982 ◽  
Vol 11 (1) ◽  
pp. 61-65 ◽  
Author(s):  
C. Elberling ◽  
C. Bak ◽  
B. Kofoed ◽  
J. Lebech ◽  
K. Sœrmark

2002 ◽  
Vol 95 (2) ◽  
pp. 671-686 ◽  
Author(s):  
M. A. Richards ◽  
S. A. Koren ◽  
M. A. Persinger

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 bands of frequencies, generating consciousness. Implications for the roles of hippocampal theta activity, cortical resonance, and Goldstone bosons in these processes are discussed.


1981 ◽  
Vol 4 (1) ◽  
pp. 51-63 ◽  
Author(s):  
J. L. Bradshaw ◽  
N. C. Nettleton

AbstractThe traditional verbal/nonverbal dichotomy is inadequate for completely describing cerebral lateralization. Musical functions are not necessarily mediated by the right hemisphere; evidence for a specialist left-hemisphere mechanism dedicated to the encoded speech signal is weakening, and the right hemisphere possesses considerable comprehensional powers. Right-hemisphere processing is often said to be characterized by holistic or gestalt apprehension, and face recognition may be mediated by this hemisphere partly because of these powers, partly because of the right hemisphere's involvement in emotional affect, and possibly through the hypothesized existence of a specialist face processor or processors in the right. The latter hypothesis may, however, suffer the same fate as the one relating to a specialist encodedness processor for speech in the left. Verbal processing is largely the province of the left because of this hemisphere's possession of sequential, analytic, time-dependent mechanisms. Other distinctions (e.g., focal/diffuse and serial/parallel) are special cases of an analytic/holistic dichotomy. More fundamentally, however, the left hemisphere is characterized by its mediation of discriminations involving duration, temporal order, sequencing, and rhythm, at thesensory(tactual, visual, and, above all, auditory) level, and especially at themotorlevel (for fingers, limbs, and, above all, the speech apparatus). Spatial aspects characterize the right, the mapping of exteroceptive body space, and the positions of fingers, limbs, and perhaps articulators, with respect to actual and target positions. Thus there is a continuum of function between the hemispheres, rather than a rigid dichotomy, the differences being quantitative rather than qualitative, of degree rather than of kind.


2021 ◽  
pp. 103-124
Author(s):  
Iain McGilchrist

Discusses the role that attention plays in constituting the world, rather than reducing phenomena to the brain level. Discusses the different kinds of attention delineated by the divided hemispheres of the brain. On the one hand the left hemisphere specialised in grasping and manipulating the world, whereas the right hemisphere specialises in relat-ing to and understanding the world. Discusses how reliance on one or the other kind of attention has cultural, psychological and social implications.


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