Even Bigger Research Dump

Intersubject Eeg Coherence: Is Consciousness a Field?

Abstract

EEG coherence was measured between pairs of three different subjects during a one-hour period practice of the Transcendental Meditation (TM) program. Coherence between subjects was evaluated for two sequential fifteen minute periods. on six experimental days, these periods preceded and then coincided with a fifteen minute period during which 2500 students participated in the TM-Sidhi program at a course over 1000 miles away. After the course had ended coherence was evaluated on six control days.

It was found that intersubject coherence was generally low, between 0.35 and 0.4, with coherence in the alpha (8–12 Hz) and beta (16–20 Hz) frequencies significantly higher than at other frequencies. on the experimental days, intersubject EEG coherence increased during the experimental period relative to the fifteen minute baseline period immediately preceding the experimental period. Coherence increased significantly from baseline to experimental periods on experimental days compared with control days (p = 0.02). This effect was particularly evident in the alpha and beta frequencies. The results reinforce previous sociological studies showing decreased social disorder in the vicinity of TM and TM-Sidhi participants and are discussed in terms of a field theoretic view of consciousness.

Field Model of Consciousness: Eeg Coherence Changes as Indicators of Field Effects

Abstract

Changes in EEG coherence patterns were used to test a field model that posits a common field of “pure consciousness” linking all individuals. In ten trials, EEG was concurrently measured from pairs of subjects, one practicing Transcendental Meditation (TM) and the TM-Sidhi technique of “Yogic Flying” (YFg) — said to enliven the proposed field of consciousness — and the other performing a computer task. Box-Jenkins ARIMA transfer function analysis indicated that coherence changes in the YF's 5.7-8.5 Hz band, the band sensitive to TM and YFg, consistently led coherence changes in the other subject's 4.7-42.7 Hz band. A clear relationship was seen among subjective reports, coherence patterns, and strength of intervention effects. These data support a field model of consciousness. Alternate explanations are explored.

Synchronous Firing and Its Influence on the Brain's Electromagnetic Field

Abstract

The human brain consists of approximately 100 billion electrically active neurones that generate an endogenous electromagnetic (em) field, whose role in neuronal computing has not been fully examined. The source, magnitude and likely influence of the brain's endogenous em field are here considered. An estimate of the strength and magnitude of the brain's em field is gained from theoretical considerations, brain scanning and microelectrode data. An estimate of the likely influence of the brain's em field is gained from theoretical principles and considerations of the experimental effects of external em fields on neurone firing both in vitro and in vivo. Synchronous firing of distributed neurones phase-locks induced em field fluctuations to increase their magnitude and influence. Synchronous firing has previously been demonstrated to correlate with awareness and perception, indicating that perturbations to the brain's em field also correlate with awareness. The brain's em field represents an integrated electromagnetic field representation of distributed neuronal information and has dynamics that closely map to those expected for a correlate of consciousness. I propose that the brain's em information field is the physical substrate of conscious awareness - the cemi field - and make a number of predictions that follow from this proposal. Experimental evidence pertinent to these predictions is examined and shown to be entirely consistent with the cemi field theory. This theory provides solutions to many of the intractable problems of consciousness - such as the binding problem - and provides new insights into the role of consciousness, the meaning of free will and the nature of qualia. It thus places consciousness within a secure physical framework and provides a route towards constructing an artificial consciousness.

EEG Frequency Ranges and Descriptions

• Delta: has a frequency of 3 Hz or below. It tends to be the highest in amplitude and the slowest waves. It is normal as the dominant rhythm in infants up to one year and in stages 3 and 4 of sleep. It may occur focally with subcortical lesions and in general distribution with diffuse lesions, metabolic encephalopathy hydrocephalus or deep midline lesions. It is usually most prominent frontally in adults (e.g. FIRDA - Frontal Intermittent Rhythmic Delta) and posteriorly in children e.g. OIRDA - Occipital Intermittent Rhythmic Delta).
• Theta: has a frequency of 3.5 to 7.5 Hz and is classified as "slow" activity. It is perfectly normal in children up to 13 years and in sleep but abnormal in awake adults. It can be seen as a manifestation of focal subcortical lesions; it can also be seen in generalized distribution in diffuse disorders such as metabolic encephalopathy or some instances of hydrocephalus.
• Alpha: has a frequency between 7.5 and 13 Hz. Is usually best seen in the posterior regions of the head on each side, being higher in amplitude on the dominant side. It appears when closing the eyes and relaxing, and disappears when opening the eyes or alerting by any mechanism (thinking, calculating). It is the major rhythm seen in normal relaxed adults. It is present during most of life especially after the thirteenth year.
• Beta: beta activity is "fast" activity. It has a frequency of 14 and greater Hz. It is usually seen on both sides in symmetrical distribution and is most evident frontally. It is accentuated by sedative-hypnotic drugs especially the benzodiazepines and the barbiturates. It may be absent or reduced in areas of cortical damage. It is generally regarded as a normal rhythm. It is the dominant rhythm in patients who are alert or anxious or have their eyes open.

What is the Frequency Range of Transcendental Meditators and Yogic Flyers?

5.7-8.5 Hz band

Theta is 3.5 to 7.5 Hz, this can be achieved through daydreaming.

Alpha is 7.5 to 13 Hz, this can be achieved through closing your eyes and relaxing

How do you cause coherence changes?

"synchronous neuronal firing, which generates coherent EM fields, was a strong correlate of attention, awareness, and consciousness. "

"The level of spatial coherence of EEG patterns — which

is a reflection of the coherence of the underlying endoge- nous em fields"

"Synchronous firing of distributed neurones phase-locks induced em field fluctuations to increase their magnitude and influence. Synchronous firing has previously been demonstrated to correlate with awareness and perception, indicating that perturbations to the brain's em field also correlate with awareness. The brain's em field represents an integrated electromagnetic field representation of distributed neuronal information and has dynamics that closely map to those expected for a correlate of consciousness."

Awareness and perception are correlates of synchronous neuronal firing, which generates coherent EM fields, which is a reflection of spatial coherence of EEG patterns.

Quotes Explaining Neuronal EM Fields

"studies with subdural and depth microelectrodes indicate that the brain’s em field has detailed spatial structure in the millimetre and sub-millimetre domain and detailed temporal structure in the sub-second domain, over a range of frequencies"

"a striking feature of EEG is the differences in electrical activity from electrode to electrode, even when less than 1 mm apart (Speckmann and Elger, 1998); indicating that the brain generates a highly structured and dynamic extracellular electric field."

"Another source of information on changes within the brain’s em field is obtained from measurements of evoked potentials (event-related potentials). Sensory evoked potentials are detected when a sensory stimulation reaches the brain and evokes a characteristic sequence of waves in the EEG. Motor evoked potentials are similarly recorded during induced motor activity."

"existence of evoked potentials demonstrates that both sensory stimuli and motor activity are associated with temporally organised perturbations to the brain’s em field."

"The human (and animal) brain therefore contains a highly structured (in time and space) endogenous extracellular em field, with a magnitude of up to several tens of volts per metre."

"endogenous em fields of tens of volts per metre are capable of generating fields of several tens of thousands of volts per metre, translating to up to several millivolts, across the 5 nm neuronal cell membrane. The form and amplitude of these fields will be continually sculpted in response to changes in brain activity. "

"Therefore, since TMS induced modulations of the brain’s em field affect brain function and behaviour, it follows that the brain’s endogenous field must similarly influence neuronal computation."

" there is very solid in vitro evidence for very weak em fields modulating neuronal function"

"very weak em field fluctuations are capable of modulating neurone-firing patterns. These exogenous fields are weaker than the perturbations in the brain’s endogenous em field that are induced during normal neuronal activity. The conclusion is inescapable: the brain’s endogenous em field must influence neuronal information processing in the brain."

"studies indicate that synchronous firing in different regions of the 21 human cortex correlates with awareness and attention. The existence of evoked potentials provides additional evidence for synchronous firing being involved in perception of stimuli and purposeful action, since although they are weak, they are much stronger than signals that would be generated from the firing of single neurones and must be due to the synchronised firing of many neurones."

"sensory information is encoded within the spatial pattern of EEG activity and thereby the shape of the underlying em field."

"modulations of the em field correlate with perception and meaning"

"these findings demonstrate that awareness and attention in man and animals, and thereby consciousness (at least in man), is associated with modulations to the brain’s em field generated by synchronisation of neuronal firing patterns."

"there is abundant evidence that the loss of awareness of repeated stimuli during habituation is associated with a reduction in amplitude of either EEG or MEG evoked potential signals"

"Loss of awareness therefore correlates with reduced disturbance to the brain’s em field"

"there is evidence that anaesthetics that decrease awareness of stimuli disrupt synchronous firing and thereby reduce the influence of the em field on neurone firing"

EEG coherence and power during Yogic Flying

http://www.sante-conscience.fr/medias/EEG-YF-1990.pdf

http://www.tandfonline.com/doi/abs/10.3109/00207459008986616

Abstract

Frontal, central and parietal power and coherence of ten subjects practicing the TM-Sidhi technique of Yogic Flying (YF) were compared to that often controls who jumped from a seated position to approximate hopping during YF. All movement artifacts were removed before signal analyses. The most significant group differences were seen in the 2.12-second period just before lift-off: the YF subjects 30–32Hz power, and theta, alpha, and beta (broad band) coherence were significantly higher than those of the controls'. Within the YF group, the first period's 30–32 Hz power and broad-band coherence were significantly higher than those of the two preceding 2.12-s periods, and of the whole YF period. There were no significant within-group differences in the control group. A similar EEG pattern has been reported during the experience of pure consciousness in TM practice, suggesting that the experience of “pure consciousness” underlies successful TM-Sidhi performance.