truly random activity would visit every point in an infinite dimensional space.) Many strange attractors have become familiar; one of the best known is the attractor for the Lorenz weather model. [Ed.: For more background information on chaos theory, see HEMI-SYNC JOURNAL, Fall 1990, Vol. VIII, No. 4.] [see: Topics/Perceptual Studies/Consciousness] One can computer-generate a system’s attractor from its governing equations, if they are known. If not, we must somehow reconstruct the attractor for the system’s behavior. The application of chaos theory to natural systems has been greatly advanced in the last decade by the development of accurate and reliable reconstruction methods, using time-series data from a single variable of the system. One such—the method of delays—is used in my current work, to which I now turn. The investigation is motivated by the following questions: Are there neural attractors characteristic of specific cognitive processes or conscious states (e.g., TMI focus levels)? Are any (such) attractors correlated with specific Hemi-Sync signals? What implications would affirmative answers have for the prospect of controlled access to specific conscious states, and for the development of Hemi-Sync-related technologies? I began to address these questions in February of 1991, when I was able to spend a week in the TMI lab, examining files from the NRS-24 brain mapping system. Subsequently, I have
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Hemi-Sync® Journal 1991-4 (Fall) · 04 Hemi-Sync® - Recovering the Attractors.pdf
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been constructing and studying two-dimensional phase portraits from EEG data on three subjects: RO (a sleep study); WR (a GATEWAY learning protocol study); and DM (unknown stimulus; short files used only for comparison). The same techniques were also applied to Hemi-Sync signals passed through the NRS-24 system without the intervention of a human brain. Initially, it was unclear how to select from the enormous database available. However, since my first task was to master techniques new to me, it seemed reasonable to search for “typical” epochs, i.e., those which resemble averaged data. Following are a few of the preliminary results which have emerged, along with some highly tentative commentary. There is a generic shape similarity among all the phase portraits from a given subject, regardless of stimulus differences, though there are many variations within the general pattern. On the other hand, there was general dissimilarity of portrait shape between subjects. These two results suggest something like a neural handwriting or signature for each subject. (To confirm this conjecture would require a controlled multisubject study.) The existence of a personal signature need not preclude attractors characteristic of specific cognitive states; that depends on particular features of the attractors involved. This question is important in that animal studies have suggested that there are such characteristic attractors (underlying odor
recognition, for example) which might be generically similar across subjects. There were several examples of rather dramatic similarity between the portraits of two sites for the same epoch in the RO data (Figure 1). Since these sites are on opposite sides of the head, hemispheric synchronization is strongly suggested. This can be confirmed by superimposing the raw EEG records, noting the high degree of overlap (Figure 2). Such apparent synchronization might have resulted from head-movement artifacts, which affect all sites similarly and are strong enough to swamp the normally weaker brain waves. However, this explanation is easily rejected by inspecting adjacent epochs. Another possible explanation is that the apparent synchronization is due to entrainment. This would be exciting if true, since it is the basic presupposition of the Hemi-Sync technology. In order to test this hypothesis directly, one would need simultaneous EEG and Hemi-Sync stimulus records, making it possible to investigate realtime correlations. Unfortunately, this was not part of the brain mapping protocol. In any case, that explanation is ruled out for examples of synchrony in the RO file which occur in the baseline epochs, when there is no auditory stimulus at all. Yet another hypothesis might be suggested. Hemispheric synchrony is known to be correlated with certain relaxed states, quite independently of external stimuli, as was amply demonstrated