This article first appeared in the August 2019 issue of Lifelines, the Life West student magazine.
Did you know that it is possible to be identified simply by how you walk? “You” can be spotted passing through the airport, or casually walking across the street to your neighborhood coffee shop.Cameras are common fixtures in our modern society. They are easily spotted on street corners, department and grocery stores, schools, churches, offices, banks, gas stations – practically everywhere, including our personal hand-held devices. To be identified, your face doesn’t need to be visible, and any disguise you use will be insignificant; therefore any attempts to be clever and “change” how you walk, look, sound, etc., will not prevent you from being identified in a sea of other people. Interesting isn’t it?
Our gait is one of the most practical traits for video-based surveillance and forensics due to each person’s unique biometrics. The Journal of Forensic Sciences demonstrated this by use of Instantaneous Posture Match algorithm. There are templates, kinematics and anthropomorphic knowledge used to determine the specific location of a person’s ankle, knee and hip (1). However, there is more to what meets the eye in observing, analyzing and labeling a person’s identity by their stride. Our gait can be the gateway in understanding the mechanisms of our neurology on a much deeper and intimate level.
The human gait or, put simply, how you walk, is known as the first Central Pattern Generator. These sensory-motor neuronal circuits that make up the Central Pattern Generator are embedded in the lumbar spine and do not require pattern sensory input (2). Once activated, these circuits innately produce rhythmic patterns of motion such as breathing, walking, running or swimming.
To perform the meticulous and intricate tasks of organizing both finite and gross movements, the brain is the responsible conductor that orchestrates with pure precision when modulating and organizing our bodies’ intelligences. Akin to your fingerprints, your voice and the molecules that make up your DNA, these neuronal circuits are the neuromodullary control pathways that emit from the brain to the body, then back to the brain again, forming the expressive, individualized and unique internal geometry that is externally manifested as your gait.
The modern-day busy and fatigued human may spend each day sitting on their bums and taking their gait for granted. They may unknowingly disregard their primary Central Pattern Generator because they are unaware that this system is a “Generator” purely because mechanical energy is being converted into electrical energy. And where does that converted electrical energy go? The electrical energy goes directly to your spinal cord, then immediately into your brain. Movement creates a direct portal into our central nervous system. Our nervous system, or warmly, our Internal Home, innervates, operates and facilitates every single aspect within our body that keeps us alive and, in doing so, allows us to express our unique self.
The modern-day mindful and energized human may be inclined to want to jump up off their bums to move with the intention of activating and lubricating the mechanisms of their Central Pattern Generator. Unbeknownst to most, there is an additional way to activate and upgrade our neurology in a way that’s sustainable so that you enhance your ability to adapt to both new and old experiences. Allow me to introduce to you the second known Central Pattern Generator of the spine, the Network Wave.
The following is an excerpt of “The Network Spinal Wave as a Central Pattern Generator” by Senzon et al., which can be found online.
This paper explores an emergent spinal wave phenomenon termed, and herein referred to as, the network wave. The network wave involves a visible undulation and specific rocking movement of spinal segments, which is elicited through gentle contacts in a defined sequence to the spine at specific areas. The areas are associated with the location of meningeal attachments of the spinal cord to the vertebral column.
The sequencing and application are aspects of network spinal analysis (NSA) care (network care). Network care is practiced by chiropractors using network spinal analysis protocols developed by Donald Epstein. The network wave was first clinically demonstrated in 1987 and has been studied since 1997 at several major universities and institutions.
The novelty and repeatability of the network wave led to empirical research in the fall of 1998 and the spring of 1999 by Edmond Jonckheere and his team at the University of Southern California in the Department of Electrical Engineering and Mathematics. Jonckheere and his colleagues studied the network wave through the use of surface electromyography (sEMG) to measure the electrical changes in the muscle system. Since 1998, sEMG has been used as a window into the central nervous system. Epstein developed the NSA protocols based on clinical practice and in response to the research into the network wave.
Initially, the sEMG signal was analyzed to determine the mathematical characteristics of the network wave. An example of how the wave is understood by examining the sEMG data is described in Figure 1, which demonstrates some of the data. Figure 1 shows the result of the wavelet decomposition (using the waviest filter) of two signals. The one on the left is the test signal, and the one on the right is the signal from the network wave. The results of the filtering show a difference in the underlying, seemingly noisy, signal at level 7 and level 8 of the decomposition.
The researchers then analyzed the sEMG signal to determine whether the network wave had different attributes based upon the NSA level of care. NSA care includes three distinct levels of care. Of this finding Jonckheere wrote in 2009, “the objectively established fact that the signals become less random and more predictable can be interpreted to reveal a better ‘organization’ of the neural circuitry at advanced levels of care.” Thus, the researchers found that the sEMG signal gets more organized with the higher levels of network care.
Other research was developed to distinguish differences between an initial electrical burst detected in the musculature and the background noise of the sEMG signal. To explore this distinction new mathematical approaches were developed.
By 2004, the sEMG signal of the network wave was best described by using mathematical modeling for a central pattern generator (CPG). CPGs are well described in the literature in relation to locomotion, such as walking, swimming and flying. However, this was the first time a CPG was observed in the spine apart from locomotion or respiration. Furthermore, while other known CPGs originate in the lumbar and thoracic spine, the neurologic circuitry for the network wave originates from the sacral and cervical spine.
The NSA protocol emphasizes the cervical and sacral areas based on a clinical analysis system, which characterizes five phases of adverse mechanical spinal cord tension (AMCT). The tension is associated with patterns of defensive physiology and intermittent areas of relaxation and ease. The defense physiology associated with AMCT is assessed by examining the stabilizing spinal subsystems (muscular, bony, and neural). Structural rigidity associated with defensive postures may lead to a static non-adaptable state, which limits the experience of novelty, and constructive change for the individual. Such a state is an inefficient use of energy. In response to the spinal contacts from the practitioner, over time, the spinal system moves from defense physiology, which is characterized by areas of muscle facilitation of the spine, decreased respiration, and other indicators of adverse mechanical cord tension (AMCT), into a state promoting the emergent network wave properties. The decreased spinal cord tension is a precursor to the development of the network wave.
The spinal wave associated with network care has been described as “an electrophysiological phenomenon running along the spine,” created by “a sensory-motor loop instability,” which stabilizes into unique oscillatory patterns. The dynamic movement patterns then reorganize into more complex behavioral wave movements, “settling in a Central Pattern Generator.” The development of the wave itself suggests a process of neurologic entrainment. The specific light-touch contacts to the spine at three unique levels of network care act as repeated stimuli leading to the entrainment of oscillators or vertebral motion segments moving in rhythmic and synchronous patterns. Development of the network wave may take several weeks to several months for an individual patient.
In describing the spinal wave associated with network care, the researchers, comprising mathematicians and electrical engineers, wrote, “The overall spinal wave procedure consists of the following steps: After sensitization of the sacral area, a light pressure contact at S3–S4 engages the sacral oscillator. From the sacral area, an electrophysiological wave phenomenon propagates upward, but initially dissipates before reaching the cervical area. Nevertheless, after some entrainment, eventually the upward wave reaches the cervical area and triggers the neck area to go in oscillation. When extended across the whole spine, the headward traveling wave reflects off the sphenoid, which happens to be the most cephalad attachment of the dura, and then travels caudally. Visually, the upward/downward traveling waves can be seen to collide, and survive the collision in some soliton-like propagation. Eventually the upward and downward waves settle in a standing wave pattern, during which the neck movement is perfectly coordinated with the pelvic movement.
With this rich evidence base, along with other research and clinical developments, Epstein used the research data to systematically refine how the network wave develops in the human nervous system.
A recent presentation by Martin-del Campo and Jonckheere explored two distinct experiments that were spaced 10 years apart and included different participants, changes to software and instrument configurations, different positioning of sacral electrodes, different sEMG amplifiers, and different analog-to-digital conversion methods. Even with all of these complex factors, they concluded that “the results upon which the Central Pattern Generator hypothesis rests are reproducible” and that “the spinal wave is a coherent movement elicited by a Central Pattern Generator, opening the road for the potential of this coherence analysis to become part of the neurological suite.” This latest research points to reproducibility of the network wave and the sEMG data it generates and also the fact that coherence, which indicates a healthy functioning nervous system, emerges along with the CPG.
Epstein hypothesized that the bound energy released from the defensive patterns associated with adverse spinal cord tension becomes available as energy to create a higher-order spinal and neural integrity. This hypothesis may help to explain why the wave increases in complexity of oscillation over time and with advancing levels of care. It may also explain the emergence of coherence at a distance between the cervical and sacral spine. The coherence is an aspect of the CPG, which emerges causally from the NSA protocols. These results point not only to the first CPG apart from locomotion in the spine but also to a healthier and more organized nervous system.
Objective measures of levels of care
In May 1999, research began to focus on level-specific changes. The researchers sought to determine whether different wave characteristics exist based specifically on the level of network care application (Table 1).
One of the defining features of each level of care in the NSA protocols includes a specific and rhythmic pattern of movement of the vertebra. When the vertebra move in such a rhythmic manner, the movement may be described as an oscillation and the vertebral motion segments as oscillators. The motion of the oscillators increases in complexity with each level of care; that is, synchronous movement develops in multiple spinal oscillators simultaneously over time. Each level of care is characterized by a new level of complexity of the wave along with the clinical findings, which indicate coupling and coherence between spinal integrity subsystems (muscles, bones, and nerves).
Research conclusions indicate a characteristic burst activity of the sEMG signals set amidst a background activity. These bursts were studied as dynamic phenomenon. The consistency of the dynamic properties of the bursts was a significant and meaningful finding at this point. The fact that there was a larger-magnitude level of organization of the burst in advanced care (level 3) as compared with levels 1 or 2 directly leads to the conclusion that the data “provide(s) an early mathematical confirmation that there is something objective in the concept of ‘Levels of Care.’ ” The sEMG signal at higher levels of care has a distinctly higher “level of organization” compared with the lower levels. Frequency and amplitude of the bursts increase with level of care. Figure 4 depicts a segment of sEMG data when the spine transitions from a level 2 response to a level 3 response.
The “burst activity” leveled off or quieted during level 2. This led Epstein to revise the level 2 protocols. The newer NSA protocols were developed to further entrain the network wave response in the spine. The new objective was to create transient instability of the stabilizing energy and information associated with defensive strategies. This was done in part by stretching the specific spinal segments to release stored tension in the connective tissues associated with the spinal joint. The released tension is used by the body in more visible movement after the stretch is complete. The increased energy and information could then become available to produce precise segmental oscillation linked to the spinal standing wave.
Coherence in the network wave
The sustained oscillation at the neck and sacrum demonstrates coherent dynamics in the spine. Coherent behavior is viewed as indicating a healthy spine and greater strength and complexity of the synaptic connections. This coherence also demonstrates an evolution over time and an increase in the organization of the neural circuitry.
The coherence observed in the spinal wave may be a result of greater synchronization of the two oscillators. The soliton, which is the result of the interaction of the spinal waves, may help in this synchronization. Coherence was demonstrated only with healthy spines. Coherence was not demonstrated in persons with spinal cord injury. This points to the possibility of self-organizing behavior in a dynamic system.
Interestingly, when a person attempts to reproduce the motion of the wave, without a specific network care application the motion visually looks similar to or even identical to the network wave; however, it lacks the unique mathematical coherence characteristic of this phenomenon. Put simply, the higher self-organization as seen with the NSA care happens only with the network applications and does not occur with faked similar movements. Of further importance, the linked precise vertebral oscillation for each level of care is a significant predictor of the coherence and self-organization characteristic of the level of care.
Spinal gateway region
After 2000, the electromyographic readings were different from the readings prior to 2000, which is likely because of Epstein’s introduction of the spinal gateway region. The initial studies were characterized by “bursting” of the spinal musculature during the wave process. The more recent data indicate less bursting and greater self-organization of the background, settling into a central pattern generator in the spine. A hypothesis is that it was the introduction of the spinal gateway region in the clinical protocol that resulted in a greater efficiency of the application and thereby a more specific response of the nervous system.
Epstein postulated that the spinal gateway regions are generally located in areas of spinal cord attachments; that they are regions of probability within the intersegmental connective tissues; and that these regions modulate between stress, tension and available energy. Epstein proposed this new structure by combining insights from the dynamic mathematical modeling of the network spinal wave, with research by Jones and Bae into the acoustic nature of acupoints, along with several other clinical and theoretical approaches. The spinal gateway is related to physiology, anatomy and subtle energy anatomy characteristic of energy medicine.
The circuitry of a CPG embedded in the spine generating the network wave points to new areas of CPG research, spinal cord injury research, as well as novel research into the spine as a mediator of pattern generation, which may dissipate adverse mechanical spinal cord tension (AMCT). The dissipation of AMCT relates to a wide range of possible research foci from spinal cord injury on the therapeutic end of the spectrum and emergent wellness lifestyles on the other end. The emergence of wellness lifestyles has been linked to a reorganization of the spinal behaviors and structures coupled to novel perceptions.
The spinal wave associated with network care has been well documented. It appears that each level of care is organized by unique central organizing principles mediated by the network wave through frequency entrained oscillation. The level of care reflects increasing levels of coherence and energy efficiency of the spinal subsystems organized through a CPG, demonstrated by distinct changes/differences in the frequency and amplitude of the bursts with respect to each level of network care (level 1, level 2, advanced). Overall, the wave implies an endogenous reorganizational system, which exists in the range between the stress and relaxation systems. It also relates to the dynamic push and pull between stability and instability associated with far-from-equilibrium living systems.
The network wave may produce a temporary reorganizational instability to the defensive physiology in the spinal system. Through this process, the wave may help the individual to achieve a higher level of adaptable stability in their nervous system organization.
The network wave occurs at a higher self-organizational threshold, in the absence of significant adverse mechanical cord tension, and with enhanced self-regulation of the spinal subsystems. With the onset of central pattern generation, modulated through the network wave, reorganizational behavior may emerge in the individual’s spine and life as a whole.
- Bouchrika, Imed, et al. “On Using Gait in Forensic Biometics.” Journal of Forensic Sciences, vol. 56, no. 4, June 2011, pp. 882-889., doi:10.1111/j.1556- 4029.2011.01793.x.
- Marder, Eve, and Dirk Bucher. “Central Pattern Generators and the Control of Rhythmic Movements.” Current Biology, vol 11, no. 23, 27 Nov. 2001, doi: 10.1016/ s0906-9822(01)00581-4