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We know that it takes a clear intention (a coherent brain) and an elevated emotion (a coherent heart) to begin to change a person’s biology from living in the past to living in the future. That combination of mind and body—of thoughts and feelings—also seems to influence matter. And that’s how you create reality.
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Joe Dispenza (Becoming Supernatural: How Common People are Doing the Uncommon)
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We could simply have used any of a number of reasonably priced handheld devices that train people to slow their breathing and synchronize it with their heart rate, resulting in a state of “cardiac coherence” like the pattern shown in the first illustration above.9 Today there are a variety of apps that can help improve HRV with the aid of a smartphone.10 In our clinic we have workstations where patients can train their HRV, and I urge all my patients who, for one reason or another, cannot practice yoga, martial arts, or qigong to train themselves at home. (See Resources for more information.)
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Bessel van der Kolk (The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma)
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We may properly and profitably amuse ourselves by distinguishing those writers who are respectively 'father-ridden,' 'son-ridden,' and 'ghost-ridden.' It is the mark of the father-ridden that they endeavor to impose the idea directly upon the mind and senses, believing that his is the whole of the work...Among the son-ridden, we may place such writers as Swinburne, in whom the immense ingenuity and sensuous loveliness of the manner is developed out of all proportion to the tenuity of the ruling idea...The ghost-ridden writer, on the other hand, conceives that the emotion which he feels is in itself sufficient to awaken response, without undergoing discipline of a thorough incarnation, and without the coherence that derives from reference to a controlling idea...It may serve as a starting point to say that, whereas failure in the father may be roughly summed up as a failure of thought and a failure in the son is a failure in action, failure in the ghost is a failure in wisdom--not the wisdom of the brain, but the more intimate and instinctive wisdom of the heart and bowels.
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Dorothy L. Sayers (The Mind of the Maker)
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How jealous I am of those I have known afraid to sleep for dreaming. I fear those moments before sleep when words tear from the nervous matrix and, like sparks, light what responses they may. That fragmented vision, seductive with joy and terror, robs rest of itself. Gratefully sunk in nightmare, where at least the anxious brain freed from knowing its own decay can flesh those skeletal epiphanies with visual and aural coherence, if not rationale: better those landscapes where terror is experienced as terror and rage as rage than this, where either is merely a pain in the gut or a throb above the eye, where a nerve spasm in the shin crumbles a city of bone, where a twitch in the eyelid detonates both the sun and the heart.
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Samuel R. Delany (Dhalgren)
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three tiers to the heart: physical, ethereal, Eternal
with each one being more spiritual and subtle
the physical heart a little brain with over 40,000 neurons
it sends and receives by electromagnetic field operations
it's got its own nervous system that senses and remembers
making decisions and giving directions to other centers
emitting enfolded energetic organizational patterns
information, that is—communicative interactions
detected outside the body by magnetometers and other people
for heart coherence listen to Pärt's “Spiegel im Spiegel”
valid are chakras and acupuncture meridians
meditate on the heart chakra to see what this means
energy meridians are strings of polarized crystalline water
bioelectric signals transmitted in connective tissue matter
information is sent along these lengths of collagen proteins
molecules of structured water allowing the transfer of protons
crystal water wires inside protein pathways
with acupuncture points being junctures in the maze
the protons, then, are what have been referred to as “chi”
a current flowing, much like electrical circuitry
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Jarett Sabirsh (Love All-Knowing: An Epic Spiritual Poem)
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Sophie thinks you were offering her a less than honorable proposition before we came to collect her, and modified your proposal only when her station became apparent.” Windham took a casual sip of his drink while Vim’s brain fumbled for a coherent thought. “She thinks what ?” “She thinks you offered to set her up as your mistress and changed your tune, so to speak, when it became apparent you were both titled. I know she is in error in this regard.” Vim cocked his head. “How could you know such a thing?” “Because if you propositioned my sister with such an arrangement, it’s your skull I’d be using that splitting ax on.” “If Sophie thinks this, then she is mistaken.” Windham remained silent, reinforcing Vim’s sense the man was shrewd in the extreme. “You will please disabuse her of her error.” Windham shook his head slowly, right to left, left to right. “It isn’t my error, and it isn’t Sophie’s error. She’s nothing if not bright, and you were probably nothing if not cautious in offering your suit. The situation calls for derring-do, old sport. Bended knee, flowers, tremolo in the strings, that sort of thing.” He gestured as if stroking a bow over a violin, a lyrical, dramatic rendering that ought to have looked foolish but was instead casually beautiful. “Tremolo in the strings?” “To match the trembling of her heart. A fellow learns to listen for these things.” Windham set his mug down with a thump and speared Vim with a look. “I’m off to do battle with the treble register. Wish me luck, because failure on my part will be apparent every Sunday between now and Judgment Day.” “Windham, for God’s sake, you don’t just accuse a man of such a miscalculation and then saunter off to twist piano wires.” Much less make references to failure being eternally apparent. “Rather thought I was twisting your heart strings. Must be losing my touch.” Vim
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Grace Burrowes (Lady Sophie's Christmas Wish (The Duke's Daughters, #1; Windham, #4))
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It couldn’t be. Devon was supposed to be in London! It was a trick of her imagination…a hallucination. Except that the air was hot and humid, spiced with the fragrance that was unmistakably his…a spicy, clean incense of skin and soap.
Apprehensively Kathleen parted her fingers just enough to peek through them.
Devon was reclining in the copper tub, looking at her in sardonic inquiry. Hot mist rose around him in a smoke-colored veil. Droplets of water clung to the tautly muscled slopes of his arms and shoulders, and sparkled in the dark fleece of hair on his chest.
Kathleen whirled to face the door, her thoughts scattering like the pins in a game of skittles. “What are you doing here?” she managed to ask.
His tone was caustic. “I received your summons.”
“My…my…you mean the telegram?” It was difficult to pull a coherent thought from the wreckage of her brain. “That wasn’t a summons.”
“It read like one.”
“I didn’t expect to see you so soon. Certainly not so much of you!” She went crimson as she heard his low laugh.
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Lisa Kleypas (Cold-Hearted Rake (The Ravenels, #1))
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Though energy fields are invisible, they shape matter. Albert Einstein said that, “The field is the sole governing agency of the particle.” Many studies show that human beings are influenced by the energy fields of others. In a series of 148 1-minute trials involving 25 people, trained volunteers going into heart coherence were able to induce coherence in test subjects at a distance. They didn’t have to touch their targets to produce the effect. Their energy fields were sufficient. When you are in a heart coherent state, your heart radiates a coherent electromagnetic signal into the environment around you. This field is detectable by a magnetometer several meters away. When other people enter that coherent energy field, their heart coherence increases too, producing a group field effect. Not only are we affected by the fields of other people; we’re affected by the energies of the planet and solar system. A remarkable series of experiments, conducted by a research team led by Rollin McCraty, director of research at the HeartMath Institute, has linked individual human energy to solar cycles. McCraty and his colleagues track solar activity using large magnetometers placed at strategic locations on the earth’s surface. Solar flares affect the electromagnetic fields of the planet. The researchers compare the ebbs and flows of solar energy with the heart coherence readings of trained volunteers. They have found that when people are in heart coherence, their electromagnetic patterns track those of the solar system. 8.15. The heart coherence rhythms of a volunteer compared to solar activity over the course of a month. A later study of 16 participants over 5 months found a similar effect. McCraty writes: “A growing body of evidence suggests that an energetic field is formed among individuals in groups through which communication among all the group members occurs simultaneously. In other words, there is an actual ‘group field’ that connects all the members” together. The results of this research confirm a hypothesis McCraty and I discussed at a conference when I was writing Mind to Matter: Not only are these heart-coherent people in sync with large-scale global cycles, they’re also in sync with each other. McCraty continues, “We’re all like little cells in the bigger Earth brain—sharing information at a subtle, unseen level that exists between all living systems, not just humans, but animals, trees, and so on.” When we use selective attention to tune ourselves to positive coherent energy, we participate in the group energy field of other human beings doing the same. We may also resonate in phase with coherent planetary and universal fields. 8.16. The brain functions as receiver of information from the field. The Brain’s Ability to Detect Fields The idea of invisible energy fields has always been difficult for many scientists to swallow. Around 1900, when Dutch physician Willem Einthoven proposed that the human heart had an energy field, he was ridiculed. He built progressively more sensitive galvanometers to detect it, and he was eventually successful.
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Dawson Church (Bliss Brain: The Neuroscience of Remodeling Your Brain for Resilience, Creativity, and Joy)
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FIELD EFFECTS Emotional contagion is just one explanation for the growth of meditation. Another is field effects. Everything begins as energy, then works its way into matter. Though energy fields are invisible, they shape matter. Albert Einstein said that, “The field is the sole governing agency of the particle.” Many studies show that human beings are influenced by the energy fields of others. In a series of 148 1-minute trials involving 25 people, trained volunteers going into heart coherence were able to induce coherence in test subjects at a distance. They didn’t have to touch their targets to produce the effect. Their energy fields were sufficient. When you are in a heart coherent state, your heart radiates a coherent electromagnetic signal into the environment around you. This field is detectable by a magnetometer several meters away. When other people enter that coherent energy field, their heart coherence increases too, producing a group field effect. Not only are we affected by the fields of other people; we’re affected by the energies of the planet and solar system. A remarkable series of experiments, conducted by a research team led by Rollin McCraty, director of research at the HeartMath Institute, has linked individual human energy to solar cycles. McCraty and his colleagues track solar activity using large magnetometers placed at strategic locations on the earth’s surface. Solar flares affect the electromagnetic fields of the planet. The researchers compare the ebbs and flows of solar energy with the heart coherence readings of trained volunteers. They have found that when people are in heart coherence, their electromagnetic patterns track those of the solar system. 8.15. The heart coherence rhythms of a volunteer compared to solar activity over the course of a month. A later study of 16 participants over 5 months found a similar effect. McCraty writes: “A growing body of evidence suggests that an energetic field is formed among individuals in groups through which communication among all the group members occurs simultaneously. In other words, there is an actual ‘group field’ that connects all the members” together. The results of this research confirm a hypothesis McCraty and I discussed at a conference when I was writing Mind to Matter: Not only are these heart-coherent people in sync with large-scale global cycles, they’re also in sync with each other. McCraty continues, “We’re all like little cells in the bigger Earth brain—sharing information at a subtle, unseen level that exists between all living systems, not just humans, but animals, trees, and so on.” When we use selective attention to tune ourselves to positive coherent energy, we participate in the group energy field of other human beings doing the same. We may also resonate in phase with coherent planetary and universal fields. 8.16. The brain functions as receiver of information from the field. The Brain’s Ability to Detect Fields The idea of invisible energy fields has always been difficult for many scientists to swallow. Around 1900, when Dutch physician Willem Einthoven proposed that the human heart had an energy field, he was ridiculed. He built progressively more sensitive galvanometers to detect it, and he was eventually successful.
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Dawson Church (Bliss Brain: The Neuroscience of Remodeling Your Brain for Resilience, Creativity, and Joy)
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We intuitively know that the heart is the center of love and empathy, and studies are showing this to be true. In fact, empathy manifests in the electromagnetic field (EMF), which is generated by the heart in amounts greater than anywhere else in the body. The heart’s EMF emits fifty thousand femtoteslas (a measure of EMF), in contrast to the ten generated by the brain.37 Other research shows that when separated from the magnetic field, the heart’s electrical field is sixty times greater in amplitude than the brain’s field.38 Through this field, a person’s nervous system tunes in to and responds to the magnetic fields produced by the hearts of other people.39 The heart’s field is therefore one of the means by which a practitioner affects patients. This effect leads to the question, What do you want to share? To generate positive outcomes for a patient, a practitioner must hold positive feelings in his or her own heart. Not only does good will profit the client, but it also benefits the practitioner as a person. A set of studies by researcher Dr. Rollin McCraty of the HeartMath Institute in California, and described in his e-book, The Energetic Heart, helps explain the importance of positive energy.40 For decades, scientists have known that information is encoded in the nervous system in the time intervals between activities or in the pattern of electrical activity. Recent studies also reveal that information is captured in hormone pulses. Moreover, there is a hormone pulse that coincides with heart rhythms, which means that information is also shared in the interbeat intervals of the pressure and electromagnetic waves produced by the heart. Negative emotions such as anger, frustration, or anxiety disturb the heart rhythm. Positive emotions such as appreciation, love, or compassion produce coherent or functional patterns. Feelings, distributed throughout the body, produce chemical changes within the entire system. Do you want to be a healthy person? Be sincerely positive as often as you can. You thus “increase the probability of maintaining coherence and reducing stress, even during challenging situations.”41 What you as a practitioner believe will be shared—everywhere and with everyone you meet.
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Cyndi Dale (The Subtle Body: An Encyclopedia of Your Energetic Anatomy)
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Local and Nonlocal Effects of Coherent Heart Frequencies on Conformational Changes of DNA.” This study showed that thinking and feeling anger, fear, and frustration caused DNA to change shape according to thoughts and feelings. The DNA responded by tightening up and becoming shorter, switching off many DNA codes, which reduced quality expression. So we feel shut down by negative emotions, and our body feels this too. But here’s the great part: the negative shutdown or poor quality of the DNA codes was reversed by feelings of love, joy, appreciation, and gratitude!
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Caroline Leaf (Switch On Your Brain: The Key to Peak Happiness, Thinking, and Health (Includes the '21-Day Brain Detox Plan'))
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The Institute of HeartMath, an internationally recognized, nonprofit research organization that helps people reduce stress, discusses an experiment titled “Local and Nonlocal Effects of Coherent Heart Frequencies on Conformational Changes of DNA.” This study showed that thinking and feeling anger, fear, and frustration caused DNA to change shape according to thoughts and feelings. The DNA responded by tightening up and becoming shorter, switching off many DNA codes, which reduced quality expression. So we feel shut down by negative emotions, and our body feels this too.
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Caroline Leaf (Switch On Your Brain: The Key to Peak Happiness, Thinking, and Health (Includes the '21-Day Brain Detox Plan'))
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In fact, the energy that is created when the heart opens makes the heart become more orderly and coherent, just like the brain, so it produces a measurable magnetic field.3 It’s this action that connects us to the unified field. And when we marry an intention (the electric charge) with that energy (the magnetic charge), we create a new electromagnetic field. Since energy is frequency and all frequency carries information, it is that elevated energy that carries your thought or intention.
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Joe Dispenza (Becoming Supernatural: How Common People are Doing the Uncommon)
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BROADCASTING RESONANCE Anchored in nonlocal consciousness, your local life begins to change. As you resonate with the cycles of nature, as your heart’s coherence conditions the energy space around you, as you vibrate to the signal of love and joy in your consciousness, you attract people and conditions that match your states and traits. Without effort, as your magnificent new signal broadcasts out around you, resonating with the music of the universe, you’ll come into synchrony with people and events that bless and delight you. You’ll discover that you’re not alone. As you tune to the great symphony of life each day, you’ll find that you’re tuned to millions of other people who are likewise attuned. With no effort at all, you’ll discover wonderful new friends and companions wherever you travel. As the light shines from your eyes, it meets the light in the eyes of others. When you’re awake, you naturally enjoy others who are awake. 9.3. Coming into synchrony. LOVING THE SLEEPER Not everyone is awake, and that’s fine. Sometimes your friends and family members are tossing in their sleep, suffering unnecessarily. Their plight touches you. You feel their misery. You would love to see them wake up, and shed those beliefs, thoughts, and habits that drag them down. You can’t force them to do so, no matter how much you love them. Everyone makes their own choice. What you can do for people who are suffering is shine brightly yourself. If they’re ready, they’ll wake up. If they don’t, trust the universe. We each wake up when the time is right. Their time might come later; it’s not up to you. You can share this book and other resources with them. You can share your story as I have shared mine, and perhaps these examples will inspire them. If and when each of us wakes up is our choice. UNLOCKING YOUR POTENTIAL As you live in synchrony with the universe, enjoying the community of other Bliss Brainers, you find new possibilities opening up. You start to unlock potential that’s been trapped inside the suffering, selfing self. Increasingly, you’re not just in Bliss Brain during meditation. You’re in the Awakened Mind state with your eyes open, going about your day. All kinds of possibilities that were previously unavailable to you now become available.
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Dawson Church (Bliss Brain: The Neuroscience of Remodeling Your Brain for Resilience, Creativity, and Joy)
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Sara took a deep breath, inhaling for five seconds, then exhaling for five seconds, then continuing the cycle until her heart didn’t feel like it was going to burst inside her chest. The breathing exercise was a version of cardiac coherence. The heart rate increases slightly when you inhale and decreases when you exhale, so timing them out could theoretically calm the parasympathetic nervous system, the central nervous system, and the brain.
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Karin Slaughter (After That Night (Will Trent, #11))
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When these ancient parts of your brain are active or rehearsing the next disaster using the DMN, they effortlessly hijack your attention. You try to meditate and repetitive negative thinking takes over. In the cage match between Caveman Brain and Bliss Brain, Caveman Brain always wins. Survival is a more important need than happiness or self-actualization. You can’t self-actualize if you’re dead. In 2015 the US National Institutes of Health estimated that less than 10% of the US population meditates. One of the primary reasons for this is that meditation is hard. Most people who start a meditation program drop out. GETTING THE BEST OF ALL WORLDS When writing my first best-selling book, The Genie in Your Genes, I experimented with many schools of stress reduction and meditation. Heart coherence. Mindfulness. EFT tapping. Neurofeedback. Hypnosis. One day I had a Big Idea: What happens when you combine them all? I began playing with a routine that did just that. Here’s what I came up with: First, you tap on acupressure points to relieve stress. Second, you close your eyes and relax your tongue on the floor of your mouth. This sends a signal to your vagus nerve, which wanders all over your body, connecting all the major organ systems. It’s the key signaling component of the parasympathetic nervous system, which governs relaxation. 4.8. The vagus nerve connects with all the major organ systems of your body. Third, you imagine the volume of space inside your body, particularly between your eyes. This automatically generates big alpha in your brain, moving you toward the Awakened Mind. Fourth, you slow your breathing down to 6 seconds per inbreath and 6 seconds per outbreath. This puts you into heart coherence. Fifth, you imagine your breath coming in and going out from your heart area, and you picture a sphere of energy in your heart. Sixth, you send a beam of heart energy to a person or place that makes you feel wonderful. This puts you into deep coherence. After enjoying the connection for a while, you send compassion to everyone and everything in the universe. Feeling universal compassion produces the major brain changes seen in fMRI scans of longtime meditators. As we’ll see in Chapters 6 and 8, compassion moves the needle like nothing else. At this point, most people drop into Bliss Brain automatically. They’re in a combination of alpha, heart coherence, and parasympathetic dominance. They haven’t been asked to still their minds, sit cross-legged, follow a guru, or believe in a deity. They’ve just followed a sequence of simple physical steps. After a few minutes of universal compassion, you again focus your beam on a single person or place. You then gently disengage and draw the energy beam back into your own heart. Seventh, you direct your beam of compassion to a part of your body that is suffering or in pain. You end the meditation by returning your attention to the here and now.
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Dawson Church (Bliss Brain: The Neuroscience of Remodeling Your Brain for Resilience, Creativity, and Joy)
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Sitting in your favorite position and closing your eyes, you tiptoe over the threshold of experience and into the mystery. You drop into the heart of the universe. You’re there. The cascade of SONDANoBe floods your brain. You’re hooked, drawn up into the light. When you emerge from meditation, you’re more compassionate, emotionally balanced, mentally coherent, effective, kind, creative, healthy, and productive. The effects ripple through the whole community around you. At the center of that circle is a great-feeling you. The Gregs of this world go for heroin, weed, or alcohol to make themselves feel good. That’s simply because they don’t realize that a far better drug is available. SONDANoBe is what addicts are really craving. They want to feel good, but they’re looking for exogenous chemicals to meet their needs. They don’t understand that what they’re searching for is right inside their own brains. The only reason those drugs feel good to the Gregs of this world is that they’re facsimiles of the substances that their own brains produce. Bliss Brain is a formula, just like the World’s Best Cocktail. It’s the World’s Best High, and it’s just as addictive. The brain that experiences SONDANoBe once can never go back to its old state. By remodeling neural tissue, SONDANoBe consolidates learning and hardwires bliss. While street drugs shrink and damage vital brain regions, SONDANoBe does the opposite. It grows your brain. It expands the brain regions that regulate your emotions, synthesize great ideas, stimulate your creativity, acquire new skills, heal your body, extend your longevity, improve your memory, and boost your happiness. The next chapter shows how a brain bathed in the chemicals of ecstasy starts to change its fundamental structure, as the software of mind becomes the hardware of brain.
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Dawson Church (Bliss Brain: The Neuroscience of Remodeling Your Brain for Resilience, Creativity, and Joy)
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A few lines from Wordsworth’s “Prelude” come to mind: “There is a dark inscrutable workmanship that reconciles discordant elements, makes them move in one society.”100 I think of the continual flux, the deconstructing and cohering of patterns of connection in the brain, moment by moment. Whether you call it Tao or dharma or God or I-don’t-have-the-slightest-idea, there is certainly a sense that we are participating in something quite extraordinary and mysterious. This time together has been like a bell ringing for five sessions over two and half days. The bell has now rung, but the reverberations have the potential to go out infinitely. We do not know what the consequences are of having eavesdropped on this conversation in His Holiness’s portable living room, but whatever the consequences may be, they will have something to do with all the questions that didn’t get answered. The challenge is to ask where those questions come from in the first place, and what your job on the planet is, whether it has to do with children, with trauma, with the military, with government, or with something else. The challenge is to ask, “What is my job on this planet, in this moment, given who I am and everything I know—including whatever has come from this dialogue? Might this inquiry begin to cohere and synchronize for us, individually and collectively, into some deeper manifestation of what it might actually mean to belong to Homo sapiens sapiens, the species that knows, and knows that it knows, in other words, the species of awareness and awareness of awareness?” Or will we go back to sleep on our way home? I was so touched by what Richie said, and I want to bow to him for holding seemingly different worlds in a way that truly has heart. I value our friendship tremendously and am deeply appreciative of the opportunity to have been able to work together to develop this meeting and host it together.
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Jon Kabat-Zinn (The Mind's Own Physician: A Scientific Dialogue with the Dalai Lama on the Healing Power of Meditation)
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But what was even more stunning was what breathing like this did to the subjects. Whenever they followed this slow breathing pattern, blood flow to the brain increased and the systems in the body entered a state of coherence, when the functions of heart, circulation, and nervous system are coordinated to peak efficiency. The moment the subjects returned to spontaneous breathing or talking, their hearts would beat a little more erratically, and the integration of these systems would slowly fall apart. A few more slow and relaxed breaths, and it would return again.
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James Nestor (Breath: The New Science of a Lost Art)
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Whenever they followed this slow breathing pattern, blood flow to the brain increased and the systems in the body entered a state of coherence, when the functions of heart, circulation, and nervous system are coordinated to peak efficiency. The moment the subjects returned to spontaneous breathing or talking, their hearts would beat a little more erratically, and the integration of these systems would slowly fall apart. A few more slow and relaxed breaths, and it would return again.
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James Nestor (Breath: The New Science of a Lost Art)
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techniques that had been developed by the Institute of HeartMath. These positive emotion-focused techniques help individuals learn to self-generate and sustain a beneficial functional mode known as psychophysiological coherence, characterized by increased emotional stability and by increased synchronization and harmony in the functioning of physiological systems.
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Rollin McCraty (The Coherent Heart: Heart-Brain Interactions, Psychophysiological Coherence, and the Emergence of System-Wide Order)
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we discuss how sustained positive emotions facilitate an emergent global shift in psychophysiological functioning, which is marked by a distinct change in the rhythm of heart activity. This global shift generates a state of optimal function, characterized by increased synchronization, harmony, and efficiency in the interactions within and among the physiological, cognitive, and emotional systems. We call this state psychophysiological coherence.
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Rollin McCraty (The Coherent Heart: Heart-Brain Interactions, Psychophysiological Coherence, and the Emergence of System-Wide Order)
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You can use the Freeze Frame technique and worksheet to quickly move from recognizing a problem or stressful issue to finding a solution that can be put into action. You can also use the Freeze Frame technique for accessing creative ideas or intuitive insights on projects you are planning or engaged in. The more you increase your coherence baseline, the more access you will have to your creative capacities.
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Rollin McCraty (HeartMath Brain Fitness Program: Connecting Heart and Mind for Optimal Performance (HeartMath Solution Book 1))
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The realization that the brain used so many different kind of chemicals, in addition to classical neurotransmitters, to communicate beween neurons was just the first step in a major conceptual shift in neuroscience. Many of these substances are neuropeptides, and most of those affect mood and behavior. The specificity of their effects resides not in the anatomical connectivity between neurons, but in the distribution of receptors within the brain. Different receptors have very different patterns of distribution, and the distributions differ between species in ways that correlate with differences in behavior.
The mere fact of a receptor-peptide mismatch in a particular brain area might have no great importance. It might be that many cells are promiscuous in the receptors that they express: If some receptors see no ligand, the cost to the cells is negligible. Profligate receptor expression might contribute to the evolvability of neural systems, and might be common because organisms with a liberal attitude to receptor expression are those most likely to acquire novels functions. Because extrasynaptic signaling does not require precise point-to-point connectivity, it is intrinsically 'evolvable': a minor mutation in the regulatory region of a peptide receptor gene, by altering the expression pattern, could have functional consequences without any need for anatomical rewiring.
That peptide receptors have distinctive patterns of expression, and that peptides produce coherent behavioral effects when given quite crudely into the brain, suggests that volume transmission is used as a signaling mechanism by many different populations of peptidergic neurons. We thus must see neuropeptides as 'hormones of the brain'.
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Gareth Leng (The Heart of the Brain: The Hypothalamus and Its Hormones)