Trauma & Childhood Trauma Dysregulates the Nervous System
”Your nervous system plays a role in everything you do.”
Polyvagal Theory by Stephen Porges ☂
(Autonomic Nervous System Regulation)
The Polyvagal Theory, developed by Stephen Porges, focuses on the role of the vagus nerve in emotional regulation, social connection, and fear response. It posits that our autonomic nervous system (ANS) has three hierarchical branches influencing our responses to stress and safety: the ventral vagal complex, the sympathetic nervous system, and the dorsal vagal complex.
What is the Vagus Nerve?
The vagus nerve, also known as the vagal nerves, are the main nerves of your parasympathetic nervous system. This system controls specific body functions such as your digestion, heart rate and immune system. These functions are involuntary, meaning you can't consciously control them.
Parasympathetic Nervous System
Ventral Vagal: Associated with social engagement and connection. When this system is dominant, we feel safe, calm, and can socially engage with others.
Dorsal Vagal: Triggers the freeze response. This system can cause immobilization or dissociation in response to extreme threat.
Sympathetic Nervous System
Activates the fight-or-flight response. This system becomes dominant when we perceive danger or threat.
Survival Modes
Fight: Engaging in confrontation or aggression to protect oneself.
Flight: Escaping or avoiding a threat.
Freeze: Becoming immobilized or dissociating in the face of overwhelming threat.
Fawn: People-pleasing or compliance as a way to diffuse conflict and ensure safety (can involve both sympathetic and parasympathetic activation. The individual may appear calm and socially engaged (ventral vagal state) but is driven by an underlying sense of threat (sympathetic arousal).
Applications
Therapeutic Interventions: Techniques like breathing, mindfulness, humming and chanting, somatic exercises, all the modalities mentioned below and safe relational experiences can help shift the autonomic state towards safety and social engagement.
Trauma Treatment: Understanding the autonomic responses helps therapists tailor interventions to support regulation and healing.
Window of Tolerance
The Window of Tolerance is a concept that describes the optimal zone of arousal where a person can function effectively. Within this window, individuals can manage and respond to everyday stressors without becoming overwhelmed or shut down.
Optimal Zone of Arousal
Inside the Window: Individuals feel calm yet alert, can think clearly, make decisions, and manage emotions effectively. The autonomic nervous system is balanced, supporting adaptive coping and social engagement.
Characteristics: Regulated heart rate, stable breathing, and a sense of control and connection.
Hyperarousal (Above the Window)
Description: When individuals exceed their window of tolerance, they enter a state of hyperarousal, driven by the sympathetic nervous system (SNS). This is the fight-or-flight response.
Symptoms: Anxiety, panic, hypervigilance, anger, and emotional overwhelm.
Physiological Responses: Increased heart rate, rapid breathing, muscle tension.
Hypoarousal (Below the Window)
Description: When individuals fall below their window of tolerance, they enter a state of hypoarousal, driven by the dorsal vagal complex of the parasympathetic nervous system (DVC). This is the freeze response.
Symptoms: Numbness, disconnection, lethargy, and dissociation.
Physiological Responses: Decreased heart rate, low energy, reduced motivation.
Factors Affecting the Window of Tolerance
Trauma and Chronic Stress, Resilience and Coping Skills, Early Life Experiences and Environmental Factors.