Polyvagal Theory Glossary alphabetical

The Polyvagal Practice™ Glossary of Terms – Alphabetical

These definitions are referenced primarily from Dr. Porges’ book, The Pocket Guide to the Polyvagal Theory: The Transformative Power of Feeling Safe. I have done my best to modify the wording to make the definitions more accessible to people without a science background. I have also taken the liberty to add terms that are not in his book to clarify Dr. Porges’ intended meaning.

While this document is most helpful for looking up terms that you don’t understand, I recommend reading the Logical Glossary of Terms first. There I present the Polyvagal Theory’s definitions more coherently and show you how the ideas interrelate. In addition, I hope reading it first will speed up your understanding of the fundamentals.

Note, I have designed this glossary with pop-up definitions of the vital Polyvagal terms. Just hover your cursor above a number like this one ^[1] (1) The parasympathetic nervous system is one of the two main divisions of the autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ventral vagal complex (the newest circuit) and the dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death.parasympathetic, and the definition text will pop up without losing your place on the page or interrupting your reading flow.

Finally, after becoming familiar with these terms and concepts, consider testing your knowledge on the iDoRecall app. You can find access to this quiz in The Polyvagal Practice™ course.

To do a search function for terms:

Mac – command “f”

PC – ctrl “f”

Adaptive and Maladaptive Behavior. Polyvagal Theory interprets behavior as adaptive if it enhances survival, minimizes distress, or influences physiological state in a manner that would optimize health, growth, and restoration. However, at times behaviors that are initially adaptive may become maladaptive. For example, this would occur if an aggressive or defensive behavior that initially helped with survival or minimized distress when experiencing a threat becomes chronically recruited when there is no threat.

Such behavior would be maladaptive since it would not optimize survival but rather compromises physiological function and amplifies distress. In addition, trauma may result in adaptive reactions in life-threatening situations that become maladaptive if repeated in less threatening situations. For example, becoming immobile or passing out to survive in life-threatening circumstances is adaptive. However, these same behaviors would not be adaptive if recruited in a scenario that is not life-threatening.  

Anxiety. Anxiety is frequently defined from a psychological (emotional feelings of fear or uneasiness) or psychiatric (e.g., anxiety disorders) perspective. Polyvagal Theory points to the ^[2] (2) Autonomic state -The neurological circuit that the autonomic nervous system chooses determines which state is turned OFF or ON in response to the environmental opportunities or threats. In addition, these circuits trigger specific thoughts, feelings, and motivations. Within Polyvagal Theory, autonomic state and physiological state are interchangeable ideas. Polyvagal Theory describes three primary circuits that control how our nervous system turns OFF or ON different autonomic states in response to opportunities or threats in the environment. autonomic state that underlies the psychological feelings that define anxiety. Polyvagal Theory assumes that anxiety is present because of a loss of access to states of safety/^[3] (3) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. ) social engagement system and the over recruitment of the    ^[4] (4) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic nervous system.

Autonomic Nervous System. The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states, it operates automatically without deliberate control. 

• The Traditional View – Traditional definitions divide the autonomic nervous system into two subsystems. These two subsystems are the ^[5] (5) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic nervous system and the ^[6] (6) The parasympathetic nervous system is one of the two main divisions of the autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ventral vagal complex (the newest circuit) and the dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death. parasympathetic nervous system. Furthermore, the traditional view emphasizes that messages travel from the brain to the body/internal organs. Therefore, this orientation states that autonomic control is top-down (the brain controls the body).

• The Polyvagal View – Polyvagal Theory divides the autonomic nervous system into three subsystems. In addition to the traditional subsystems, sympathetic and parasympathetic, Polyvagal Theory adds the              ^[7] (7) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown).  ventral vagal complex. The ventral vagal complex is a newer branch of the ^[8] (8) The parasympathetic nervous system is one of the two main divisions of the autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ventral vagal complex (the newest circuit) and the dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death. parasympathetic nervous system. It is responsible for highly cooperative and reciprocal behaviors. Activation of the VVC transforms the aggressive and defensive energy of the ^[9] (9) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic activation and ^[10] (10) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal shutdown into higher brain behaviors like play and intimacy. 

   

  Polyvagal Theory emphasizes that the communication between the brain and body/internal organs is bidirectional. In this model, 80% of the messages that control neurological states come from the body/internal organs to the brain. Likewise, only 20% of the messages travel from the brain to the body. Therefore, unlike the traditional view, the brain and the body influence each other, and the more significant influence is from the body to the brain (bottom-up regulation, the body controls the brain).

Polyvagal Theory also finds a link between our nervous system’s ^[11] (11) Neuroception is the process through which the nervous system evaluates risk without requiring awareness. This automatic process involves brain areas that assess environmental cues of safety, danger, and life threat. Once neuroception detects danger, the physiological state automatically shifts to optimize survival. Although we are usually not aware of cues that trigger neuroception, we tend to be mindful of the physiological shift (i.e., interoception). Sometimes we experience this as feelings of unease in body areas like the gut and heart, typically called intuition or a felt sense. Alternatively, neuroception can also trigger physiological states that support trust, social engagement behaviors, and the building of solid relationships. neuroceptive (unconscious) choices and the muscles that control the face, neck, and head. These muscles include ears, eyes, and voice which collectively make up what Polyvagal Theory calls the ^[12] (12) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language.  Social Engagement System. Consequently, an individual’s autonomic state shows up in the sound of their voice and facial expressions.

Autonomic State/Physiological State. The neurological circuit that the autonomic nervous system chooses determines which state is turned OFF or ON in response to the environmental opportunities or threats. In addition, these circuits trigger specific thoughts, feelings, and motivations. Within Polyvagal Theory, autonomic state and physiological state are interchangeable ideas. Polyvagal Theory describes three primary circuits that control how our nervous system turns OFF or ON different autonomic states in response to opportunities or threats in the environment.

1. Ventral Vagal Complex– supports social engagement behaviors and turns ON when we feel safe in our environment. To feel safe in our environment, we must first feel safe in connection with other people also known as ^[13] (13) Co-regulation – Within Polyvagal Theory, co-regulation involves the mutual regulation of physiological states between individuals. The basis for co-regulation starts within the mother-infant relationship. The mother calms her infant, and the infant response by relaxing and settling down. The infant’s calm reaction to the mother’s vocalizations, facial expressions, and gestures has the reciprocal effect of calming the mother. If the mother is unsuccessful in calming her infant, the mother’s physiological state also becomes dysregulated. The quality of co-regulation between the mother, her husband, immediate family, and community largely determines the quality of the co-regulation between the mother and her child.The more successful co-regulation a child experiences growing up, the more likely they will experience health, happiness, and longevity. Conversely, when a mother is easily dysregulated, often because of a lack of support, successful co-regulation with her child may be rare or none. Lack of co-regulation in childhood often leads to a life of struggle in learning, relationships, and career, higher levels of depression, anxiety, and a higher risk of early death from chronic disease. co-regulation. 
   
   
2. Sympathetic Nervous System – turns ON mobility (flight/flight) aggressive or defensive behaviors to face danger.
    
3. Dorsal Vagal Complex– turns ON immobile (shutdown) or defensive actions against life threat and includes behaviors like death feigning/playing dead.

Attachment. Attachment is a psychological construct reflecting a solid emotional bond between two individuals, such as the relationship between a mother and her child. Polyvagal Theory focuses on the features of safety manifested in the ^[14] (14) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language.  social engagement system that enables attachment to occur. For example, prosodic voices, positive facial expressions, and welcoming gestures trigger feelings of safety and trust ( successful ^[15] (15) Co-regulation – Within Polyvagal Theory, co-regulation involves the mutual regulation of physiological states between individuals. The basis for co-regulation starts within the mother-infant relationship. The mother calms her infant, and the infant response by relaxing and settling down. The infant’s calm reaction to the mother’s vocalizations, facial expressions, and gestures has the reciprocal effect of calming the mother. If the mother is unsuccessful in calming her infant, the mother’s physiological state also becomes dysregulated. The quality of co-regulation between the mother, her husband, immediate family, and community largely determines the quality of the co-regulation between the mother and her child.The more successful co-regulation a child experiences growing up, the more likely they will experience health, happiness, and longevity. Conversely, when a mother is easily dysregulated, often because of a lack of support, successful co-regulation with her child may be rare or none. Lack of co-regulation in childhood often leads to a life of struggle in learning, relationships, and career, higher levels of depression, anxiety, and a higher risk of early death from chronic disease. co-regulation ) These thoughts and feelings emerge spontaneously when the social engagement system is activated.

Biological Rudeness. Our nervous system evolved to anticipate reciprocal interactions (safe and friendly) from others when we are engaged socially. When we do not receive a safe, reciprocal response and instead receive a dismissing or a hostile reaction, there is an immediate and massive shift in the ^[16] (16) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states, it operates automatically without deliberate control. autonomic nervous system to a state that supports defense. This violation frequently promotes an emotional response of being hurt and a personal narrative of being offended.

Co-regulation. Within Polyvagal Theory, co-regulation involves the mutual regulation of physiological states between individuals. The basis for co-regulation starts within the mother-infant relationship. The mother calms her infant, and the infant response by relaxing and settling down. The infant’s calm reaction to the mother’s vocalizations, facial expressions, and gestures has the reciprocal effect of calming the mother. If the mother is unsuccessful in calming her infant, the mother’s physiological state also becomes dysregulated. The quality of co-regulation between the mother, her husband, immediate family, and community largely determines the quality of the co-regulation between the mother and her child.

The more successful co-regulation a child experiences growing up, the more likely they will experience health, happiness, and longevity. Conversely, when a mother is easily dysregulated, often because of a lack of support, successful co-regulation with her child may be rare or none. Lack of co-regulation in childhood often leads to a life of struggle in learning, relationships, and career, higher levels of depression, anxiety, and a higher risk of early death from chronic disease.

Death Feigning/Shutdown System. Under certain conditions, the nervous system reverts to a primitive defense response characterized by appearing dead. This defense pattern is typical for invertebrates, such as reptiles and amphibians, that evolved before mammals showed up on the evolutionary scene. These animals don’t consume much oxygen so playing dead isn’t a risk to their brains. However, mammals are great consumers of oxygen, which can cause trouble during death feigning. Polyvagal Theory sees a connection between states of shutdown that deprives the brain of oxygen and traumatic activation.

Depression. Depression is a common and severe mood disorder that influences feelings, thoughts, and behavior. Polyvagal Theory assumes that depression has a physiological state profile that the Polyvagal Theory could explain. Hypothetically, people who are depressed would have difficulty engaging states of safety through the ^[17] (17) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system and instead are stuck in states of dangers and life threat. Consequently, they tend to get stuck in a loop between too much ^[18] (18) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic activation and too much ^[19] (19) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal shut down with little or no access to feelings of safety, play, or intimacy.  

Dissociation is a process of losing a sense of the present. This disconnection results in a lack of flow between thoughts, memories, surroundings, and actions. For many people, dissociation is within the range of ordinary psychological experiences and manifests as daydreaming. For others, dissociation is sufficiently disruptive and results in a loss of personal identity, and creates severe difficulties in relationships and functioning in everyday life. Trauma history is frequently associated with dissociation’s profound disruptive effects and can result in a psychiatric diagnosis. Polyvagal Theory interprets dissociation in response to life threat as activation of the        ^[20] (20) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal circuit, triggering immobilization, death feigning/playing dead. Thus, Polyvagal Theory sees that dissociation is usually an adaptive reaction to life-threatening challenges. The exception is situations when people become so dissociated that they become traumatized and, in rare cases, die from a lack of oxygen to the brain.

Dorsal Vagal Complex. The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors.

Dysregulation, also known as emotional dysregulation, refers to a poor ability to manage emotional responses or keep them within an acceptable range (window of tolerance). Dysregulation can refer to a wide range of emotions, including sadness, anger, irritability, and frustration. Polyvagal Theory interprets dysregulation as an inability to activate the ^[21] (21) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown).  ventral vagal complex’s feelings of safety. When the VVC can’t turn on, the nervous system will over recruit aggressive energy from the ^[22] (22) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic nervous system. Causes of dysregulation include inadequate ^[23] (23) Co-regulation – Within Polyvagal Theory, co-regulation involves the mutual regulation of physiological states between individuals. The basis for co-regulation starts within the mother-infant relationship. The mother calms her infant, and the infant response by relaxing and settling down. The infant’s calm reaction to the mother’s vocalizations, facial expressions, and gestures has the reciprocal effect of calming the mother. If the mother is unsuccessful in calming her infant, the mother’s physiological state also becomes dysregulated. The quality of co-regulation between the mother, her husband, immediate family, and community largely determines the quality of the co-regulation between the mother and her child.The more successful co-regulation a child experiences growing up, the more likely they will experience health, happiness, and longevity. Conversely, when a mother is easily dysregulated, often because of a lack of support, successful co-regulation with her child may be rare or none. Lack of co-regulation in childhood often leads to a life of struggle in learning, relationships, and career, higher levels of depression, anxiety, and a higher risk of early death from chronic disease. co-regulation, ^[24] (24) Maladaptive neuroception – Damage to the nervous system/components of the social engagement system can cause neuroception to miss interpret the environment. When this happens responses to the environment become ineffective and often harmful to self and others. Danger signals can be interpreted as safe and cues of safety as dangerous. Examples include moving towards someone who is threatening instead of running or seeing a harmless person as a threat and attacking them instead of befriending them. maladaptive neuroception, and damage to the ^[25] (25) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. ) social engagement system components like the vagus nerve.

Faulty/Maladaptive Neuroception. Damage to the nervous system/components of the ^[26] (26) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system can cause neuroception to miss interpret the environment. When this happens responses to the environment become ineffective and often harmful to self and others. Danger signals can be interpreted as safe and cues of safety as dangerous. Examples include moving towards someone who is threatening instead of running or seeing a harmless person as a threat and attacking them instead of befriending them.

Fight/Flight Defense System. Fight and flight behaviors are the predominant mobilized defense behaviors of mammals. Activation of the ^[27] (27) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic nervous system is necessary to support the shift in physiology required to flee or fight. When danger is detected that and not settled by peaceful means, the ^[28] (28) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown). ventral vagal circuit turns OFF, and the ^[29] (29) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system withdraws.  Simultaneously, the sympathetic nervous system turns ON, releasing the intense energy necessary for fight and flight behaviors. Sympathetic activation is our second oldest neurocircuit.

Freeze activates when sympathetic (fight/flight) behaviors have failed to result in a return to safety. When this happens, the dorsal vagal circuit turns ON, mixing immobility with mobility. This balance of energetic forces creates a state of immovability with alertness (freeze).

Interoception. Interception is the process describing both conscious feelings and unconscious monitoring of bodily functions by the nervous system. Interoception, similar to other sensory systems, has four components:

1. Sensors located in internal organs to evaluate internal conditions.

    

    

2. Sensory pathways convey information from the organs to the brain via the ^[30] (30) Vagus nerve – The vagus is the tenth cranial nerve and represents the parasympathetic nervous system’s main element. The vagus nerve oversees numerous crucial bodily functions, including control of mood, immune response, digestion, and heart rate. Additionally, it is a central component of the autonomic nervous system. It establishes a bidirectional connection between the brain and the gastrointestinal tract (the gut-brain axis). Essentially, the vagus nerve functions as an information superhighway sending data about the state of the inner organs to the brain. The vagus nerve also allows for regulation of the internal organs through practices like yoga and mindful breathing. Polyvagal Theory points to the evolutionary changes in the autonomic nervous system/vagus nerve unique to mammals. This special wiring allows mammals to be safe in close connection, facilitating highly cooperative and reciprocal relationships. vagus nerve.

    

    

3. Brain structures interpret sensory information and regulate the organ’s response to the changing internal conditions.

    

4. Motor pathways via the vagus nerve communicate information from the brain to the organs and change the organs’ state.

In Polyvagal Theory, interoception is the unconscious process providing the communication to the brain of changes in the physiological state of the internal organs. For example, in contexts in which there are cues of risk or safety, interoception would occur after neuroception. In some cases, interoception may result in conscious awareness of bodily responses. In contrast, neuroception always occurs outside conscious awareness.

Intimacy. During intimacy, the ^[31] (31) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown). ventral vagal circuit is ON, which engages the ^[32] (32) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system. The VVC safety mixes with the ^[33] (33) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal circuit’s shut down energy. This mix enables immobilization to occur without recruiting defensive behaviors. This state is active during times of intimacy and in trusting relationships.

Mixed States – There are situations when turning ON two circuits at a time will create a nervous system state that is more adaptive than just one. The four mixed states are ^[34] (34) Play – Polyvagal Theory defines face-to-face interactive play as a ” neuro exercise” that enhances our physiological states through co-regulation. Play activates neuro mechanisms that support mental and physical health. Interactive play as a neuro exercise requires synchronous and reciprocal behaviors between individuals. In this manner, face-to-face interaction involves an awareness of each other’s safety level within the exchange. The social engagement system remains active for everyone through mutual feelings and signals of safety. Maintaining joint feelings of security ensures that the sympathetic activation does not hijack the nervous system, resulting in playful movements turning into aggressive behavior.  play, a mix of safety and sympathetic action energy, ^[35] (35) Intimacy – During intimacy, the ventral vagal circuit is ON, which engages the social engagement system. The VVC safety mixes with the dorsal vagal circuit’s shut down energy. This mix enables immobilization to occur without recruiting defensive behaviors. This state is active during times of intimacy and in trusting relationships. intimacy, a mix of safety and dorsal vagal stillness, ^[36] (36) Negotiate/Appease – This group of behaviors engages in the presence of the unknown/novelty. The instinctual response to encountering something novel is finding a reaction to it that doesn’t lead to aggressive or defensive behaviors. Examples include soothing a distressed person, repairing a rupture in a relationship after an upset, and calming a predatory person to save yourself. When this happens, the ventral vagal circuit is ON (states of safety) with just a touch of fear from sympathetic activation.   Negotiate/Appease , a mix of safety with a touch of sympathetic action with fear and ^[37] (37)Freeze activates when sympathetic (fight/flight) behaviors have failed to result in a return to safety. When this happens, the dorsal vagal circuit turns ON, mixing immobility with mobility. This balance of energetic forces creates a state of immovability with alertness (freeze). freeze, an equal mix of sympathetic action energy and dorsal vagal stillness.

Negotiate/Appease . This group of behaviors engages in the presence of the unknown/novelty. The instinctual response to encountering something novel is finding a reaction to it that doesn’t lead to aggressive or defensive behaviors. Examples include soothing a distressed person, repairing a rupture in a relationship after an upset, and calming a predatory person to save yourself. When this happens, the ^[38] (48) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown).) ventral vagal circuit is ON (states of safety) with just a touch of fear from ^[39] (49) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic activation.   

Neuro Exercise. Polyvagal Theory focuses on specific neuro practices that provide opportunities to optimize our conscious and autonomic unconscious (neuroceptive) responses to our environment. In the Polyvagal perspective, neuro exercises work best in the context of social interaction. These interactions consist of a challenge that disrupts an individual’s equilibrium, followed by a repair back to balance. When practiced effectively, neuro exercises promote greater resilience/self-regulation.

Neuroception. Neuroception is the process through which the nervous system evaluates risk without requiring awareness. This automatic process involves brain areas that assess environmental cues of safety, danger, and life threat. Once neuroception detects danger, the physiological state automatically shifts to optimize survival. Although we are usually not aware of cues that trigger neuroception, we tend to be mindful of the physiological shift (i.e., ^[40] (38) Interception is the process describing both conscious feelings and unconscious monitoring of bodily functions by the nervous system. interoception ). Sometimes we experience this as feelings of unease in body areas like the gut and heart, typically called intuition or a felt sense. Alternatively, neuroception can also trigger physiological states that support trust, ^[41] (39) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement behaviors, and the building of solid relationships.

Neurofeedback (NFB) is also called Neurotherapy and EEG (electroencephalogram) biofeedback. NFB is a type of biofeedback used to teach self-regulation resulting in reduced symptoms and better function. Typically, sensors are placed on the scalp to measure activity, with measurements and feedback coming from video displays, sound or visual signals. In some forms of neurofeedback, like LENS (low energy neurofeedback system), radio waves are sent through the cranial nerves.  These waves stimulate the brain and help it consider more expansive connections. All forms of NFB training stimulates the brain to reorganize itself, affecting symptoms controlled by the central nervous system. Examples include anxiety, ADD and ADHD, anger, depression, panic attacks, learning disabilities, traumatic brain injuries, concussions, PTSD, headaches, and chronic stress. Essentially neurofeedback rewires the brain and retunes ^[42] (40) Neuroception is the process through which the nervous system evaluates risk without requiring awareness. This automatic process involves brain areas that assess environmental cues of safety, danger, and life threat. Once neuroception detects danger, the physiological state automatically shifts to optimize survival. Although we are usually not aware of cues that trigger neuroception, we tend to be mindful of the physiological shift (i.e., interoception). Sometimes we experience this as feelings of unease in body areas like the gut and heart, typically called intuition or a felt sense. Alternatively, neuroception can also trigger physiological states that support trust, social engagement behaviors, and the building of solid relationships. neuroception allowing for more adaptive behavioral responses to daily stressors.

Parasympathetic Nervous System. The parasympathetic nervous system is one of the two main divisions of the ^[43] (41) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states, it operates automatically without deliberate control.  autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ^[44] (42) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown). ventral vagal complex (the newest circuit) and the ^[45] (43) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death. 

Phylogeny. The study of relationships among different groups of organisms and their evolutionary development. Phylogeny attempts to trace the evolutionary history of all life on the planet based on the hypothesis that all living organisms share a common ancestry. The phylogenetic tree shows the relationships among organisms. Relationships are determined by shared characteristics, as indicated through the comparison of genetic and anatomical similarities.

Phylogenetically Ordered Hierarchy. Polyvagal Theory proposes that the components of the autonomic nervous system react to challenges following a hierarchy. In this model, the phylogenetically newer circuits respond first. Therefore, the autonomic nervous system faces challenging events in the following way:

1. Ventral Vagal Complex – In response to potential danger, our ^[46] (44) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states, it operates automatically without deliberate control.  autonomic nervous system will turn ON the social engagement system in an attempt to create safety and peace by befriending, appeasing, soothing, or making a truce with a potential threat.

    

2. Sympathetic Nervous System – If ^[47] (45) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement strategies fail, the autonomic nervous system turns OFF the VVC and turns ON mobility in an attempt to fight off a threat. If fighting doesn’t work, our ^[48] (46) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states, it operates automatically without deliberate control.  ANS will attempt to avoid the danger by running away.
    
3. Dorsal Vagal Complex – If fighting or running fails to result in safety, the autonomic nervous system turns OFF the SNS and turns ON freeze or shut down behaviors. The DVC will attempt to hide from or placate the life threat by becoming immobile and non-threatening.  

Physiological State. See autonomic state. 

Play. Polyvagal Theory defines face-to-face interactive play as a ” neuro exercise” that enhances our physiological states through co-regulation. Play activates neuro mechanisms that support mental and physical health. Interactive play as a neuro exercise requires synchronous and reciprocal behaviors between individuals. In this manner, face-to-face interaction involves an awareness of each other’s safety level within the exchange. The ^[49] (47) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system remains active for everyone through mutual feelings and signals of safety. Maintaining joint feelings of security ensures that the sympathetic activation does not hijack the nervous system, resulting in playful movements turning into aggressive behavior.  

Polyvagal (poly- “many” + vagal “wandering”) The many branches of the wondering vagus nerve.

Polyvagal Theory.  A collection of evolutionary, neuroscientific, and psychological claims which point to the vagus nerve’s role in emotional regulation, social connection, fear response, and trauma. Dr. Stephen Porges is the author of Polyvagal Theory.

Prosody. Prosody is the tone, pitch, and rhythm of a voice that conveys emotions. Polyvagal Theory emphasizes that mechanisms of the vagus nerve control prosody. Therefore, prosody reflects the physiological state of the speaker and changes accordingly. Furthermore, prosody is the primary way mammals broadcast their physiological state to other mammals, e.g., “It’s not what you said, it’s how you said it.”  

Safety. Polyvagal Theory proposes a neurophysiological model of safety and trust. The model emphasizes that safety is defined by the neurological capacity to feel safe and not by removing threats. Feeling safe is dependent on three conditions:

1. The ^[50] (50) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states it operates automatically without conscious control. autonomic nervous system cannot be in a state that supports defense.

    

2. The social engagement system must be ON to down-regulate ^[51] (51) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic activation and contain the sympathetic nervous system and the ^[52] (52) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal circuit. This down-regulation keeps aggressive and defensive energies within an optimal range to support health, growth, and restoration.

    

3. ^[53] (53) Neuroception is the process through which the nervous system evaluates risk without requiring awareness. This automatic process involves brain areas that evaluate environmental ques of safety, danger, and life threat. Once neuroception detects danger, the physiological state automatically shifts to optimize survival. Although we are usually not aware of cues that trigger neuroception, we tend to be mindful of the physiological shift (i.e., Interoception). Sometimes we experience this as feelings of unease in body areas like the gut and heart, typically called intuition or a felt sense. Alternatively, this system also triggers physiological states that support trust, social engagement behaviors, and the building of solid relationships. neuroception must report that the environment is safe. States of safety turn on when the window of individual stress tolerance is maintained. When the window of tolerance is functionally limiting (maladaptive), neuro exercises can expand it.  

Self-regulation. Emotional self-regulation describes an individual’s ability to regulate behavior without another person’s aid. Examples include monitoring and managing their energy states, emotions, thoughts, and behaviors in acceptable ways resulting in positive well-being, loving relationships, and deep learning. It is how we deal with stressors and, therefore, lays the foundation for all other activities. Moreover, it is often a defining feature of an individual’s ability to deal with stress in a novel situation.

Polyvagal Theory does not view self-regulation as a learned skill. Instead, it interprets self-regulation behaviors resulting from the nervous system that can maintain feelings of safety in the absence of receiving cues of safety from another person. The theory emphasizes that co-regulation builds up an individuals’ capacity to self-regulate. In this framework, mutual, synchronous, and reciprocal interactions between individuals that define co-regulation are considered potent neurological exercises. These exercises enhance self-regulation by building and reinforcing neuropathways to states of safety.    

Singing. Polyvagal Theory interprets singing as a neuro exercise of the ^[54] (54) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system. Singing combines breathing that speeds up and slows down the heart in conjunction with the activation of the face and head muscles, middle ear muscles for listening, and vocal intonation muscles. Thus, singing provides an opportunity to exercise the entire integrated social engagement system. Chants, oral readings, and playing a musical instrument would also offer opportunities to exercise the system.    

Social Engagement System. The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language.

When our social engagement is successful, we will feel in synch with others, i.e., co-regulation supports health, happiness, and longevity. However, suppose our social engagement system is underdeveloped from lack of adequate co-regulation in childhood, traumatic experiences as an adult, and/or damage to a part(s) of the social engagement system. In that case, it can cause problems with co-regulating, which creates challenges with self-regulation. Damage to physical or neurological parts of the social engagement system can also create difficulties with co-regulation. For example, autistics have trouble processing sounds in their environment, including trouble processing human speech. This challenge makes social engagement a lot more stressful for the autistic, which makes self-regulation more difficult.   

Social Connectedness. The state of being connected and having a close relationship with other things or people. From a Polyvagal perspective, social connectedness, present in trusting relationships, is biologically essential for our health and happiness. Humans can also feel connected to animals. Typically, this happens with other mammals who have a reciprocal ^[55] (55) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language.   social engagement system similar to ours. Common examples include pets like dogs, cats, and horses.      

Sympathetic Nervous System. The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors.

The Focus System is a therapy based on equivalent science to the safe and sound protocol with the addition of movements and mental exercises associated with therapeutic play. The Focus System uses these building blocks to improve the foundational parts of the brain-body connection. As a result, this therapy builds up the nervous system’s ability to handle many environmental stressors without becoming overwhelmed. After building a solid foundation, the therapy increases mental and emotional resilience. This change commonly manifests as better self-regulation, more rewarding relationships, and improved academic and professional achievement. The Safe and Sound Protocol sets the foundation for a resilient nervous system by expanding access to states of safety. The Focus System expands on this foundation and completes organizational neurological connections essential for successful life outcomes.

The Polyvagal Practice. The application of Polyvagal Theory, as opposed to an intellectual examination of it. The practice’s goal is to optimize health, growth, and healing in oneself, loved ones, and the greater community. Better outcomes are accomplished by exercising the nerves, muscles, and organs of the social engagement system to allow more access to states of safety and greater self-regulation/stress resilience.

The Practice. The application or use of an idea, belief, or method, instead of an intellectual examination of theories relating to it. The activity of doing something, again and again, to become better at it.

The Safe and Sound Protocol. The SSP developed from Dr. Porges’s research project focused on figuring out how to help autistic children with their ^[56] (56) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement and learning challenges. He discovered that a dysfunction of the middle ear muscles was a significant factor in why autistics have trouble processing sound. He also found that their trouble processing sound connected to their challenges with regulating emotional states. From these findings, Dr. Porges and his colleges designed a sound therapy using modified popular songs to wake up the dysfunctional middle ear muscles. The autistic children that received this therapy experienced more successful social engagement, less sound sensitivity, and better self-regulation.

The initial studies showed so much promise that Dr. Porges tested SSP therapy on people with other health issues. These people’s health problems included difficulties with social engagement and sensory sensitivities. In multiple studies, this therapy has been proven effective in helping individuals with multiple sensory sensitivity, learning disabilities, PTSD, anxiety, and depression. Essentially, the Safe and Sound Protocol expands the nervous system’s capacity to feel safe by correcting a hearing system that misinterprets the everyday sounds in the environment as threatening. This misinterpretation of the environmental sounds causes ^[57] (57) Maladaptive neuroception Damage to the nervous system/components of the social engagement system can cause neuroception to miss interpret the environment. When this happens responses to the environment become ineffective and often harmful to self and others. Danger signals can be interpreted as safe and cues of safety as dangerous. Examples include moving towards someone who is threatening instead of running or seeing a harmless person as a threat and attacking them instead of befriending them. maladaptive neuroception.

The Vagal Brake. A metaphor that reflects the effect of the ^[58] (58) The ventral vagal complex is the evolutionarily newest circuit of the parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of sympathetic activation (fight/flight) or dorsal vagal (shutdown). ventral vagal pathways on the heart when neuroception perceives the environment as safe. The vagal brake slows the heart rate lower than the normal levels. Additionally, the vagal brake inhibits the evolutionarily older circuits of fight/flight and shutdown. When the vagal brake is engaged, it has a calming effect on the ^[59] (59) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states it operates automatically without conscious control. autonomic nervous system ))autonomic nervous system. This calm state transforms aggressive ( ^[60] (60) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic ) and defensive ( ^[61] (61) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal ) circuits into behaviors that support social bonding, health, growth, and restoration.

Trauma/Post-Traumatic Stress Disorder (PTSD). PTSD is a psychiatric diagnosis reflecting the consequences of experiencing a traumatic event such as sexual assault, severe injury, war, earthquake, hurricane, or a bad accident. From the Polyvagal Theory perspective, many of the problems associated with PTSD point to a dysfunctional ^[62] (62) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system, an inability to access feelings of safety, and a low threshold of stress tolerance. This focus on the response is consistent with the observation that there are significant variations in individual reactions to events that are considered traumatizing.

Examples of experiences regarded as traumatizing include war, rape, and the death of a loved one. Therefore, a typical ‘traumatic’ experience may be devastating to one individual and disrupt their life. In contrast, others may experience the same event and be more resilient and less affected. Because of the range of reactivity and recovery trajectories, Polyvagal Theory focuses on the profile of an individual’s autonomic/neuroceptive reaction, not the factual details of the event. In other words, specific events don’t traumatize people; a lack of resources to generate feelings of safety during and after an event is what causes trauma. Additionally, events generally considered safe and non-threatening to most people can cause trauma in other people.

Vagus Nerve. The vagus is the tenth cranial nerve and represents the ^[63] (63) The parasympathetic nervous system is one of the two main divisions of the autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ventral vagal complex (the newest circuit) and the dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death. parasympathetic nervous system’s main element. The vagus nerve oversees numerous crucial bodily functions, including control of mood, immune response, digestion, and heart rate. Additionally, it is a central component of the ^[64] (64) The autonomic nervous system regulates the body’s internal organs without conscious awareness. As the name states it operates automatically without conscious control. autonomic nervous system. It establishes a bidirectional connection between the brain and the gastrointestinal tract (the gut-brain axis). Essentially, the vagus nerve functions as an information superhighway sending data about the state of the inner organs to the brain. The vagus nerve also allows for regulation of the internal organs through practices like yoga and mindful breathing. Polyvagal Theory points to the evolutionary changes in the autonomic nervous system/vagus nerve unique to mammals. This special wiring allows mammals to be safe in close connection, facilitating highly cooperative and reciprocal relationships.

Ventral Vagal Complex(VVC). The ventral vagal complex is the evolutionarily newest circuit of the                         ^[65] (65)The parasympathetic nervous system is one of the two main divisions of the autonomic nervous system. The parasympathetic nervous system has two subdivisions, the ventral vagal complex (the newest circuit) and the dorsal vagal complex (the oldest circuit). The primary neuro pathway of this system is the vagus nerve and primarily support health, growth, and restoration. However, under certain life-threatening conditions, the dorsal vagal complex, which would typically support homeostasis and health, can respond defensively and inhibit functions that support wellbeing. When the dorsal vagal complex is over activated it can cause trauma or even death. parasympathetic nervous system. It includes nerves of the brain stem, gut, face, middle ear, voice, and neck. These nerves can influence heart and lung regulation, which can optimize our responses to opportunities or threats. The VVC is the neuro circuit that allows us to feel safe and act “civilize.” The VVC reduces the influence of the more ancient circuits of ^[66] (66) The sympathetic nervous system is one of the two main divisions of the autonomic nervous system and is the second oldest neurocircuit. It functions to increase metabolic outputs throughout the body, like blood flow to support body movement. Polyvagal Theory focuses on the SNS’s role in increasing cardiac output to support body movements and fight-flight behaviors. sympathetic activation (fight/flight) or ^[67] (67) The dorsal vagal complex consists of behaviors oriented towards defensive immobility, including death feigning. For example, suppose fight and flight behaviors fail to create a safe resolution to danger. In that case, the sympathetic circuit turns OFF, and the DVC turns ON. This change shuts down mobility and prepares the body to survive by being still and non-threatening. The dorsal vagal complex is the most ancient of our neurocircuits and is associated with our reptilian ancestors. dorsal vagal (shutdown). 

Yoga. Polyvagal Theory breaks down yoga practices involving breath into specific neuro exercises of the vagus nerve. Pranayama yoga is functionally a yoga of the ^[68] (68) The social engagement system emerges from a heart–face connection that coordinates the heart with the face and head muscles. The initial function of the social engagement system is to coordinate sucking-swallowing-breathing-vocalizing of an infant. As we grow, it is what we use to communicate with other humans/animals. We convey our physiological state to others and receive information about the physiological state of others through our social engagement system. This information is shared using voice tone, pitch and rhythm (prosody), facial expressions, and body language. social engagement system. It involves neuro activities of both breath and the face and head muscles and is commonly practiced with other people.