THE KNOWN AND HYPOTHESIZED NEUROPHYSIOLOGY OF THE SLEEP EASY METHOD
"Everything is interesting if you go into it deeply enough."
The information in this paper was reviewed by Robert Scaer, M.D., leading medical expert on the neurophysiology of trauma, and author of The Body Bears the Burden and The Trauma Spectrum.
The Sleep Easy method consists of simple steps of feeling particular body sensations that create the actual feeling of falling asleep or back to sleep. These body sensations are described below, along with the known and hypothesized muscles, nerves, hormones, and neurotransmitters involved. The information in this paper is absolutely not necessary to know for the Sleep Easy method to be effective. The method is very simple and natural. I have written the paper below for those who are curious about the neurophysiological mechanisms that occur with each step of the Sleep Easy procedure. Some of the information below is known to be true, such as the names of muscles and nerves affected by this sleep procedure. Other information comes from hypotheses about neurophysiological pathways. If the elements below seem complex, that is just due to this way of explaining them in detail. When you learn the Sleep Easy method, these elements blend together in an easy and natural feeling—the natural feeling of sleep.
SAFETY IN THE NERVOUS SYSTEM
For years, much focus was placed on two branches to the autonomic nervous system:
1. The parasympathetic nervous system is in charge of relaxation. The parasympathetic system's response to stress is to shut down energy utilization and slow bodily functions. It influences our gut and visceral organs. A major aspect of the parasympathetic system is the dorsal vagal system, which is the oldest system in our evolution. These nerves are unmyelinated, which means they are not under direct control of cerebral cortex of the brain.
2. The sympathetic nervous system, which is in charge of arousal. Its response to stress is fight or flight. The sympathetic nervous system influences our circulatory system, as well as spinal and limb movement used to fight or flee.
Stephen Porges, Ph.D., in "The Polyvagal Theory of Evolution," [Porges, SW (2011). The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-regulation. New York: W.W. Norton & Company.] presents evidence that there is a third aspect of the autonomic nervous system: The mammalian ventral vagal system, which is evolutionarily newer. Ventral vagal nerves are myelinated, so the higher brain can exert greater influence over this system. Porges calls this the "Social Nervous System" or "Social Engagement System" because it influences complex social behaviors that have survival value, especially for primates. For example, the human child requires a longer period of care-taking time before he or she is self-sufficient. The social nervous system controls a wide range of behavioral responses that make it possible for bonding, communication, and love. to occur to enable this extended period of mother-child bonding. The social nervous system influences voice, hearing, visual contact, and facial expression, each of which are capable of triggering neurotransmitters that induce pleasurable sensations in the caregiver. These facial-vocal cues also make it possible for humans to communicate to each other that we are safe and are available to enter into non-threatening relationship. This makes it possible to work and live together, cooperate, procreate, and create a society together. This social nervous system modulates stress and promotes pro-social behavior by exerting an inhibitory effect on the sympathetic nervous system.
Throughout the history of psychology, much attention has been given to the "fight or flight" reflex as a response that is essential to survival. The other very different ability essential to survival is our ability to become quiet and calm enough to get close to, trust, and work with each other. This is closely related to the ability to relax.
Porges postulates that for survival we often utilize these three autonomic functions in sequence. We often first engage the ventral vagal or social nervous system. With this we can voluntarily calm ourselves and communicate in the situation. If that does not work, we engage the sympathetic nervous system to fight or flee. If that does not work we engage the dorsal vagal nervous system to immobilize and shut down.
The Sleep Easy procedure addresses all three aspects of the nervous system. It is hypothesized that the element of Sleep Easy activate the ventral vagal system to calm the sympathetic nervous system, allowing you to draw your attention away from your surroundings and focus your attention inward. You calm the sympathetic nervous system, engage the parasympathetic (relaxation) nervous system, and activate the ventral vagal system in a way that is also often called the vagal brake, which calms the sympathetic nervous system. Moving far beyond relaxation, we arrive at a state in which the body and mind feel safe enough to have the external sensory system become much less sensitive and to enter into a sleep. Early in human evolution, when people were living in caves, this was not safe because people had to be on guard for the possible intrusion of predators. In our current state of evolution, while we certainly want to take steps to ensure safe external conditions, we need to gently "convince" our nervous system to feel safe. The Sleep Easy procedure is a way to create the neurophysiology of deep safety.
While the Sleep Easy procedure is simple to use, the neurophysiological cascade it involves is elaborate. Below are the neurophysiological functions, some of which are known to be involved, some of which are hypothesized to be involved.
We often hold tension in our tongue without being aware of it, so the tongue is part of the involuntary nervous system. When your tongue is tense it is fairly easy to allow those muscles to relax. So the tongue muscles also are under the influence of your voluntary nervous system. This makes your tongue a "bridge" between the involuntary and voluntary nervous systems, which gives you an effective "opening" into deeper relaxation. Your tongue muscles send signals to the brain, which then assist in relaxing the muscles in your face, head, neck, shoulders, and chest.
With the intricate, precise and subtle movements the tongue is required to make, the tongue is one of the most complex muscles in the body. As such it contains many nerves. When you allow your tongue to relax, the concentration of nerves in your tongue sends signals (though the V Cranial trigeminal sensory and IX glossopharyngeal sensory nerves) of relaxation to your brain, which then relaxes your throat, face, neck, and upper torso.
Thinking primarily occurs in two forms: images and words. Thought-words often take the form of subvocal talking. It is hypothesized that when a person does subvocal talking, his or her tongue moves in micromovements. In the Sleep Easy procedure we influence that connection in the reverse direction — relaxing the tongue can help quiet internal subvocalizations that are part of thinking and lead to a quieter mind.
Why is it that just allowing your tongue to be slightly calmer can have such an important calming effect on the nervous system? If you remember back to high school science class, a homunculus is a diagram of the human body in which the body parts are depicted in size that corresponds to their complexity and importance of function. In a homunculus, the tongue is HUGE:
* Your tongue is specialized for making small, precisely controlled movements (whereas your knees make large movements that are all relatively similar).
* Humans put great emphasis on speech and the tongue is central to speech.
* The tongue provides a large amount of sensory information.
* Large areas of the brain's cortex, and large number of brain cells control sensation and movement of the tongue.
This provides a clue as to why is it that just allowing your tongue to be slightly calmer can have such an important calming effect on your entire nervous system.
Trying or struggling to relax your jaw often just creates more tension. Jaw muscles are tired of being tense, so instead of forcing them to relax, simply allow the masseter muscles (at the jaw hinges) to relax. When you do this, it diminishes pressure in the temporomandibular joint. People often report that this also generates feelings of relaxation deep inside the ear. What may be occurring is that the third branch of the trigeminal nerve affects the medial and lateral pterygoid muscles around the Eustachian tubes. Through the pharyngeal branch of the vagus nerve, the levator veli palati and tensor veli palatini muscles relax. These muscles also affect the Eustachian tubes.
To support jaw relaxation, relax your tongue above the jaw, relax your throat below the jaw and allow your upper and lower teeth to separate a bit. Your jaw then begins to relax by itself, without your directly trying to make it relax.
When people are stressed, they often constrict their throat muscles. Yet, unlike a tension headache, your throat is fairly easy to voluntarily relax. You do not make your throat relax because force creates tension. Instead, you give your throat permission to relax, you allow your throat to relax. This sends signals to the brain (though the IX glossopharyngeal sensory nerves) that create relaxation in head, neck, and upper torso. Throat relaxation is particularly effective because the throat is located near the brain stem, and engaging brain stem activity shifts us into a more basic state of functioning that occurs without thought.
Many people report that they had not been previously aware of the feeling of constriction they held in their throat, and they are pleased to discover that it is fairly easy to allow the throat to relax. When you feel very safe, it is likely that your throat is more relaxed. We utilize this connection in reverse—relaxing your throat helps you feel safe.
When you yawn, the back of your throat relaxes. Conversely, when you allow your throat to relax, it sends signals to your brain (via the IX Glossopharyngeal sensory nerve) similar to those of yawning. These signals are associated with a feeling of relaxation, letting go, and moving towards sleep.
When you relax your throat, the cricopharangeus (a ring-like muscle in your throat near the top of the esophagus) relaxes and sends neural signals to the brain, which recognizes these as signals of deep relaxation approaching sleep. The brain sends neural signals of relaxation to face, head, neck, and upper torso.
The flow of air in the windpipe gently stimulates the posterior interior wall of the trachea. Through the IX glossopharyngeal sensory nerve, this signals the brain to shift into functions characteristic of deep relaxation.
Allowing the throat to become slightly calmer may also affect the Vagus nerve (the tenth cranial nerve), causing the parasympathetic effect pathway to influence deeper relaxation to flow from the core of the body, outward into the limbs.
When an infant is hungry, she has a lot of tension in the mouth-throat area. After breast-feeding (or bottle feeding) is complete and the infant is satisfied, the mouth-throat tension relaxes and the infant often falls asleep. This is evidence of a neurological connection between primal satisfaction and mouth-throat relaxation. We utilize this connection in reverse. Creating mouth-throat relaxation leads to a feeling of satisfaction that helps create a calmness that opens the inner pathway to sleep.
The vocal chords necessary for speech (larynx) are located in the throat, so during speaking there is considerable activity in the throat area. Much of our thinking is in the form of talking to ourselves — subvocal speech. When you allow the throat to relax, you are relaxing a center associated with speech, which can help quiet internal subvocal speech that is part of thinking, thus helping quiet your mind.
The tongue, throat, and larynx are important centers contributing to our ability to communicate, be social and survive. As previously mentioned, in order to sleep, we need to disengage from external social interaction and move into an internal state of relative immobility. When you relax the throat and larynx, it helps activate your ventral vagal nervous system involved with social interaction. This helps reduce sympathetic activity involved in hyperarousal. This brings to the forefront the ventral vagal nervous system involving parasympathetic activity, and relaxation. This helps you feel safe enough to ease into sleep.
The throat physically connects the head with the rest of the body. When you relax and open the throat, it opens a "pathway" for your head and thinking mind to connect with your body.
When you breathe through your nose the incoming air travels first upwards towards the bridge of the nose, the mucosal surface of the rhinion. In contrast, when you relax your tongue and throat and relax into the sleep breath, it feels as though the incoming air moves more horizontally (rather than vertically upward) and stimulates the floor of the interior nasal passage, the inferior aspect of the nasal vestibule. This has a calming effect on the nervous system.
INNER SLEEP BREATH SOUND
When you allow your throat to relax, the sound of your breath moves deeper inside you to your sinuses, inner airways, throat, and upper chest (rather than your nostrils or mouth). This becomes the quiet inner sound your breath makes when you are deeply asleep (different than snoring). It is also the sound your breath makes when you feel very safe.
The ventral vagal nervous system enables us to soothe ourselves. When you engage the ventral vagal nervous system soothe yourself, you breathe more quietly. Conversely, when you breathe more quietly, you engage the ventral vagal nervous system, which helps calm body, mind and emotions into parasympathetic resting state.
PATHWAY FROM INNER SOUND, TO EAR, TO BRAIN
The vagus nerve (X cranial nerve) has a branch connected to the external surface of the eardrum. The vagus nerve carries about 75% of all parasympathetic (relaxation) signals to the internal organs. The inner-breath sound vibrates the bones in the inner ear, which causes mild stimulation of the eardrum. The vibration of the eardrum activates the vagus nerve, which has the effect of relaxing the individual.
With earplugs, you hear that inner-breath sound through bone-tissue conduction inside your body instead of hearing it through the air. Listening through bone-tissue conduction helps shift your nervous system from sympathetic alert functioning to parasympathetic relaxation functioning. Phylogenetically, reptiles with their chin on the ground hear vibrations on the ground through bone conduction. Therefore, bone conduction sounds engage your older reptilian nervous system and brain stem, and this helps disengage your evolutionarily newer cognitive/thinking nervous system. Inner-breath sound has a calming effect on the nervous system, by calming the inner ear and ear drum which then send those signals to the brain.
The ear is completely formed and mature at 4 1/2 months of gestation, making it the first organ to become fully developed. This is an indication of the fundamental importance of our sense of hearing. While in utero, the fetus is able to listen to sounds of mother's breathing, heartbeat, digestion, and blood circulating, as well as mother's speech and sounds in mother's environment. The inner sound of breath accessed by the Sleep Easy procedure is related to the sound of mother's breath heard in the womb through the mother's tissues and the fluids inside the womb. Listening to this sound can engage that neurological memory helping to bring about a primal, protected feeling that helps lead to sleep.
The inner ear, especially the vestibular system (including the cochlea and semicircular canals), gives your body its sense of movement (including rotational movement, acceleration, deceleration, gravity, and balance. This information is transmitted from the ear to the brain and from the brain to every muscle in the body, which makes the ear one of the most important sources of information to the brain and body. Alfred Tomatis, M.D., noted French physician and researcher, claimed that the ear provides the majority of sensory input to the brain. He noted that of the sound-sensing hairs in the cochlea (inner ear), 80% of them are tuned to respond to vibrations 3000 Hz or higher. From this observation, Dr. Tomatis considered ultra high-pitched sounds to be a nutrient for the nervous system. He has written, "The vibration of the inner ear is transmitted as electrical waves to the brain. This 'charging and energizing' the brain is as vital to the brain's functioning as oxygen and glucose are to its metabolism."
Neurological signals from the ear travel not just to the auditory cortex of the brain, but also to the frontal lobes and, most importantly, to the limbic area where information is processed and affects our emotional response. Of special importance is the amygdala, which evaluates and signals if we are in danger or not. The decrease or absence of amygdala-generated signals helps create the feeling of being safe. Andrew Weil, M.D., created a wonderful illustration of the connection between the ears and the limbic or emotional center: When watching a dramatic scene in a video, turn off the sound and notice how the intensity of your emotional experience diminishes. Much of our emotional experience comes from the sounds we hear.
When you hear a loud sound, your heart starts racing. This provides evidence of the neurological connection between ear, brain, nervous system, and heart. Conversely, when your eardrum vibrates with the soothing inner-breath sound, that neurological connection calms your heart, like a lullaby calms a baby.
The soft inner sound of the sleep breath is similar to calm ocean waves or the sound of a gentle breeze. The earth is necessary for life and calming nature sounds bring us back to a comfortable connection with the earth and its natural rhythms.
The field of Psychoacoustics studies the effect sound has on the brain. A sound in a cathedral bounces off the distant walls and creates an expansive reverberation. If this sound is recorded and you listen to this recording (especially when wearing headphones) that expansive sound creates a feeling of being in a large space. In a related way, the inner sleep breath sound is much more resonant and expansive (although quieter) than the regular sound of breath. Listening to this sound can create a feeling of internal expansiveness. While anxiety and tension are accompanied by contraction, relaxation is associated with expansion. Listening to this internal expansive sound can generate deep relaxation.
It is interesting to note that while we have eyelids with which we can close our eyes, we do not have controllable earflaps with which we can close our ears. This is because in earliest times while cave people slept, they still needed to be able to hear if dangerous animals or people were approaching. Our sense of hearing is therefore even more fundamentally connected to survival than our sense of sight. The sympathetic nervous system keeps us alert to attend to perceived survival needs. Many people who have difficulty sleeping report that they become alert at the slightest sound. Sleep Easy gives you a way to turn your sense of hearing inward and, by listening to this special soothing inner-breath sound, to reduce the intensity of neural transmissions generated by the inner ear. This calms the sympathetic nervous system, calming the feeling of hyper-alertness that had been connected with perceived survival needs.
When you are stressed, your breath make a higher pitch sound, perhaps in the range of 170 cycles-per-second (near the note F below middle C). As you use the Sleep Easy procedure, the inner sound of your breath takes on a deeper pitch, vibrating at fewer cycles-per-second, perhaps as low as 98 cycles per second (near the note G, one-and-one-half octaves below middle C). This produces a slower moving sound wave that causes the eardrum to move more slowly. The neurological signal from the ear drum and middle and inner ear gets transmitted to both the auditory cortex and limbic areas of the brain. It is possible that the slower vibration of the sound entrains brainwaves to slow down to fewer cycles-per-second, shifting brain activity from a rate characteristic of waking thought to a rate characteristic of relaxation and then sleep.
When you hear loud sounds, the muscles in your middle ear become tense in response to the noise. Conversely, when you listen to the sleep breath, the muscles of your middle ear relax. The above mechanisms calm the sympathetic arousal nervous system and engage the parasympathetic relaxation nervous system.
As previously stated, the inner ear is anatomically tuned to be especially sensitive to sound above 3000 Hz. While the primary inner sound of the sleep breath may be a deeper pitch, breath sound includes a spectrum of frequencies including the gentle background higher-pitched hiss that is often termed "white noise." That background sound is also soothing and nourishing to your brain.
Mothers in all cultures sing lullabies to their infants. This is an indication that we are neurologically "wired" to be soothed by calming sounds. Even for someone who had a traumatic in-utero or childhood experience and who did not experience being soothed by their mother, listening to the inner sound of the sleep breath can help provide nurturing that was not provided in early childhood. This is deeply calming and helps you feel protected and safe enough to sleep.
With the Sleep Easy procedure, your eyes and eyelids relax and become still by themselves. Creating and looking at internal images is a primary form of thinking. Looking at internal images is usually accompanied by eye movement. When your eyes become more still, you create fewer images, which helps calm thought activity.
CARDIORESPIRATORY SYSTEM: BREATH
With the Sleep Easy procedure, your breath becomes more comfortable. Constricted breathing patterns loosen and the feeling of your breath begins to move into the diaphragm area. Your diaphragm becomes softer and more flexible. Your lungs, chest, and diaphragm send signals to your brain (via X dorsal vagus sensory nerve), which recognizes these as signals of relaxation approaching sleep.
When you inhale, your heart beats a bit more quickly. When you exhale, your heart rate slows down. This coupling of heart rate and breath cycle is called respiratory sinus arrhythmia (RSA) or breathing heartwave. It is thought that RSA occurs due to several primary mechanisms:
a. When you inhale, stretch receptors in your thorax (chest cavity) and lungs sense when your lungs inflate. These receptors send afferent (from-body-to-brain) signals to the medulla in the brain to stop sending inspiratory signals to the lungs, so the lungs stop inflating. The heart also responds to signals sent by these thoracic stretch receptors by increasing its rate.
When you inhale, your diaphragm moves down, creating a negative pressure in your thoracic chest cavity. This directs more blood into the heart, which increases its rate to accommodate the increased rate of filling.
b. During exhalation the sensory neurons that respond to lung stretching decrease their firing rate. This signal is sent to the brain, which increases parasympathetic signals to the heart resulting in a decrease in heart rate.
c. The rhythmic firing of respiratory neurons from the medulla in the brainstem cause the lungs to inflate and deflate. These medullary respiratory neurons also have a direct influence on cardiomotor neurons, influencing heartbeat patterns.
d. Respiratory movements affect blood pressure, which influences heart rate.
With Sleep Easy, you learn a variety of ways to have your breath bring a feeling of safety and comfort to your heart. This association fosters a phase integration of the breath pattern and heart activity. Since this phase integration is strongest during sleep or rest, Sleep Easy helps you replicate the breath-heart interaction that occurs during sleep.
CARDIORESPIRATORY SYSTEM: HEART
The nervous system within the heart is so sophisticated that some neurologists qualify the heart as a "little brain." It is a "central switch" in the nervous system. As we calm the heart, it helps calm the brain, mind and body.
When you are in deep non-dream (non REM) sleep, your heart beats more slowly and your blood pressure decreases. You also experience a decrease in cardiac contractility—the amount of force in each heartbeat—which affects how strong and loud or calm and quiet your heart seems. Sleep Easy helps your heart beat more slowly, decreasing your blood pressure and cardiac contractility—patterns associated with sleep.
When you measure a pulse rate, you are measuring beats over a period of time. However, beats do not occur in perfect metronomic rhythm. Some beats are slightly faster, some are slightly slower. Pulse rate is an average of those varied rates. The variation of pulse rate is due to the interplay of the parasympathetic (relaxation) nervous system (which establishes the baseline heart rate) and the sympathetic (arousal) nervous system (which makes the heart beat more quickly). This beat-to-beat variation is called heart rate variability (HRV). One element of this is that your heart rate increases as you inhale and decreases as you exhale. When you are healthy or relaxed or feeling good, your heart is more "flexible." This means there is actually greater variation between the faster heartbeat that occurs as you inhale and the slower heart rate that occurs as you exhale. When you are feeling relaxed, your heart rate also changes in rhythm with your breath, creating a smooth sine wave. When you are stressed, your heart is less "flexible," so there is less variation in your heart rate. Your heart rate changes in a more erratic way that is not synchronized with your breathing. It is postulated that the Sleep Easy procedure helps create heart rate variability to patterns associated with well-being and sleep.
The sleep breath also helps the diaphragm feel more soft and flexible, which calms the heart. "When the diaphragm is open, the heart is free to act without fear or apprehension." (Stone, R., Polarity Therapy Vol. 2, p. 46, CRCS Publications, Sebastopol CA, 1986). Heart begins to beat more slowly and quietly, heart rate variability (HRV) increases (an indicator of health), and your heart feels safe, comfortable, and peaceful—generating the feeling that occurs when you are deeply asleep.
Chinese medicine postulates that when we sleep, spirit/mind rests in the heart, and that insomnia is caused by agitation in the heart so the mind has no place to rest. Chinese medicine also talks about "overheating" in the heart from stress, and overwork. The Sleep Easy procedure gives you a way to calm your heart, cultivating a comfortable resting place for your mind.
HEART CALMING ADRENAL OVERACTIVITY
Many people who have difficulty sleeping describe feeling both tired and "wired." The wired feeling is often due to chronic overactivity of the adrenal glands, which flood the body with stress hormones. The hormones and neurotransmitters produced by a calm heart can have a calming effect on the adrenal glands.
HEART AFFECTING BRAIN
The heart sends "relaxation signals" to the brain via the following pathways:
a. Neurological: The heart communicates with the brain through the afferent vagal fibers in the spinal column. It is significant that there are a greater number of neural connections going from the heart to the brain (afferent) than there are going from the brain to the heart (efferent) indicative of the heart's effect on the brain.
The heartbeat pattern signals the brain stem which then sends "calming signals" to the heart and body. Heart-to-brain stem signals also cascade up into higher centers of the brain and influence their activity and function. One area affected is the cortex—the part of the brain that governs higher thought and reasoning capacities. With Sleep Easy a calmer heart reduces cortical processes, thus helping quiet the mind.
When your blood pressure reduces, the baroreceptors (pressure receptors in the wall of the heart) send this information to the brain, which slows cortical activity.
The heartbeat pattern afferently signals the amygdala through the tractus solitarius—the brain area that processes emotional experience, especially the data that indicates whether you are safe or in danger. Thus, the heart sends signals to the brain that it is safe enough to relax into sleep.
b. Biophysical: With every beat, the heart generates a pressure wave (pulse) that travels rapidly though the arteries. This blood pressure wave affects the brain's electrical activity and affects the cells of the body. In addition, the heart sounds spread through the chest and abdomen affecting the organs. The contraction of the heart also affects the cerebrospinal fluid that influences brain activity.
c. Hormonal: The heart secretes a hormone called atrial natriuretic factor (ANF). Nicknamed the "balance hormone," it affects many of the regulatory regions of the brain, as well as the blood vessels, kidneys, and adrenal glands. This hormone also inhibits the release of stress hormones and reduces sympathetic (excitatory) activity.
When you protect and calm your heart with the Sleep Easy procedure it helps your heart release oxytocin, a hormone involved with bonding and love. This helps you feel more comfortable to relax into sleep.
d. Electromagnetic: The neural activity of the heart generates a strong electromagnetic field. Using devices that detect electromagnetic fields, this field can be measured anywhere on the body. It is postulated that the heart's electromagnetic energy acts as a synchronizing signal for the entire body-mind system.
As the body's central rhythmic oscillator, the heart continually transmits neural, hormonal, rhythmic, pressure and electromagnetic signals to the brain and throughout the entire body. With elements of the Sleep Easy method, you calm your heart, which sends calming signals to your brain and your brain sends calming signals that calm your thoughts, emotions, the nervous system, and the entire body.
COHERENCE OF HEART, BRAIN, BREATH AND BODY
With the Sleep Easy procedure, the breath can shift the heart rhythm into a smooth sine wave-like pattern. Mathematical analysis of the low-frequency band (0.1 Hz) of heart-rate variability shows an orderly pattern called heart rhythm coherence. Through these mechanisms, this heart rhythm can inhibit brain cortex activity causing the brain to create more relatively harmonic, sine-like waves. This influences the autonomic nervous system, cognitive function, and emotions, thus setting up a more ordered and harmonious interaction among respiration, heart, rhythmic oscillations in blood pressure, low-frequency brain rhythms, sympathetic and parasympathetic branches of the autonomic nervous system, craniosacral rhythms, organs, immune system functioning, cognition and emotions. It therefore has been proposed that the heart is the primary conductor in the body-mind system. Even considering the importance of the heart, impairment of HRV is probably based on brain/autonomic dysregulation due to trauma. Coherence allows the whole system to operate more efficiently and effectively, creating a feeling of well-being that has a beneficial effect on health and performance. Coherence among mind-body systems occurs during peaceful non-dream sleep, especially in younger people. It also occurs during the experience of sustained positive emotions as well as during deep relaxation. Creating mind-body coherence makes it easier to sleep.
DIAPHRAGM, SOLAR PLEXUS AND ABDOMEN
The Sleep Easy method provides a way for the diaphragm, solar plexus and abdomen to feel softer, looser and calmer.
The diaphragm affects the vagus nerve, which affects our ability to be calm.
A common symptom of stress or anxiety is a feeling of tension in the solar plexus, as well as in the area of the stomach and upper and lower abdomen. People commonly hold tension in the rectus abdominus muscles, which then put pressure on the solar plexus.
The abdominal area is richly endowed with neurotransmitters and neuromodulators. Many substances are found in both the bowel and the brain. Because of this, the abdomen is sometimes referred to as the Enteric Nervous System (ENS). Recent work has also shown a vast overlap of neuropeptide activity in the gut and the brain. Ninety-five percent of the body's serotonin is contained in the nerves of the small intestine, which helps explain that we feel strong emotions like fear, anticipation, and love deep in our guts as well as our minds.
When the diaphragm, solar plexus and abdomen are calmed with the Sleep Easy method, those areas transmit signals to the brain, in part through the vagus nerve, which then shifts into brain activity characteristic of reduced anxiety. This can signal the adrenal glands to reduce production of stress hormones such as adrenaline and cortisol.
Neural signals from your tongue, soft palate, jaw, neck, throat, ears, lungs, chest, diaphragm, and especially your heart are transmitted to the amygdala and thalamus in the brain stem. The primary role of the amygdala is to identify threatening sensory input based on past experience. The absence of threat-identification signals from the amygdala make sleep easier. Your brain then signals other body regions, calming your emotions and creating the experience of safety and security. Neural signals are sent from the brain stem to the cerebral cortex, modulating brain waves to slow their frequency and become smoother and more even. By changing brain wave activity from beta waves (waking) to alpha waves (relaxation and light sleep) and quieting thoughts, this eventually leads to theta and delta brain waves (deeper sleep).
Your brain also reduces the number and intensity of signals sent to the muscles in your face, head, neck, shoulders, and chest. Reduced neural activity causes those muscles to relax as muscle fibers elongate and decrease the number and intensity of nerve firings among muscle cells.
The suprachiasmatic nucleus (SCN), located in the hypothalamus, is the body's internal clock. The SCN relays the information to the pineal gland, which releases melatonin. Melatonin release lowers the body temperature and promotes sleep.
As you begin to move towards sleep, neurons in your lower brain stem and anterior hypothalamus inhibit production of alertness-promoting neurotransmitters, including: norepinephrine (noradrenaline), histamine, cortisol, adrenocorticotropic hormone (ACTH), acetylcholine, excitatory amino acids glutamate and aspartate, thyroid stimulating hormone (TSH), serotonin, aminergic neurotransmitters, and peptides such as corticotrophin releasing factor (CRF), thyrotropin releasing factor (TRF), and vasoactive intestinal peptide (VIP).
The reticular activating system (RAS) is a group of neural structures from the brain stem to the top layer of the cerebral cortex, which activate the cerebral cortex, and thus thinking. As we move towards sleep, there is an increase in neuronal discharge in the raphe nucleus, the nucleus tractus solitarius (NTS), and ventrolateral preoptic nucleus (VLPO). This inhibits the reticular activating system, which causes us to quickly lose interest in demanding thought. GABA-containing neurons shut off neurons within the reticular activating system, which also inhibits neural activity in the thalamus and cortex (thinking). The basal forebrain begins firing a pattern of neuronal discharge that accompanies the initial stages of sleep.
As you come closer to sleep, chemicals with sleep-promoting properties are released into your bloodstream. These include endorphins, melatonin, insulin, adenosine, cholecystokinin, prostaglandins, interleukins, growth hormone, and prolactin. Like tipping the first domino, relaxing your tongue triggers this entire neurophysiological cascade that facilitates sleep.
OTHER IMPORTANT ELEMENTS
Bringing Awareness Inside Your Body: Your mind travels quickly (it can go to the moon and back in an instant). Your body travels infinitely more slowly. Therefore, bringing your awareness (mind) inside your body helps mental activity become slower. Many of our thoughts are about things that are outside of us, such as work, other people, and situations. Bringing your awareness back inside your body helps bring it away from those external stressors, which helps your mind slow down.
Downward Movement: We do not rise asleep, we fall asleep. Mental overactivity is often experienced as activity in the head. The sequence of creating comfort in your tongue, jaw, throat, breath (chest-lungs), heart and abdomen is a neurophysiological "step ladder" that brings awareness from the head, down into your more comfortable body.
Kinesthetic-Auditory Sensory Channels: As noted in the Session One CD, creating and maintaining internal images often involves effort that can keep you awake. Note that the Sleep Easy procedure does not depend upon visualization. Instead, this procedure engages primarily the kinesthetic and auditory sensory systems. This combination of kinesthetic and auditory (but not visual) is the set of senses we experienced while in utero. Perhaps by reengaging this particular sensory experience we help the nervous system remember the state in which (for most of us) we were protected and safe.
Circadian Clock: Our bodies have an internal clock that affects our sleep-wake cycle or circadian rhythm. Unusual hours resulting from shift work, crisis work, or being in a different time zone can create a circadian rhythm disturbance. Trying to sleep at unusual hours is often difficult because your body and mind do not feel sleepy. This problem is exacerbated by the internal struggle that comes from trying to get to sleep. With Sleep Easy, people often find that bringing deep comfort to the core physiological functions presented here can help move their body and mind towards sleep, even at unusual hours. In these situations, the goal is to have sleep be reliably easier.
REFERENCES AND ACKNOWLEDGMENTS
For a detailed understanding of the Polyvagal Theory: Porges, S.W. (1995). Orienting in a defensive world: Mammalian modifications of our evolutionary heritage. A Polyvagal Theory. Psychophysiology, 32, 301-318.
For a simpler understanding of the Polyvagal Theory: Chitty, J. Polyvagal Theory, the Triune Autonomic Nervous System, and Therapeutic Applications. Go to www.energyschool.com and click on "Writings."
Appreciation to John Chitty and Michael Gismondi, M.A., for helpful information about the vagal nervous system. John has created a training for polarity therapy and craniosacral therapy. For more information, visit www.energyschool.com, or call 303-443-9847. Michael produces seminars on trauma resolution.
Much of the information in the sections on breath, heart and brain comes from McCraty, R., & Atkinson, M. Psychophysiological Coherence. In A. Watkins & D. Childre (Eds.), Emotional Sovereignty. Amsterdam: Harwood Academic Publishers. Further information can also be found at http://www.heartmath.org, or 831-338-8500.
Some of the neurological information in the Ear-To-Brain section came from Ron Minson, M.D., Director of the Center For Inner Change, Denver, Colorado. 303-320-4411.
If the elements described in this paper seem complex, that is just due to this way of explaining them in detail. The Sleep Easy method is very simple to use and will work well if you do not know the information contained in this paper. When you learn the Sleep Easy method, these elements blend together in an easy and natural feeling—the natural feeling of sleep.