Anxiety vs Anxiety Disorders - Understand the Physiology of Fight or Flight Response
Anxiety and anxiety disorders are related concepts, but they have distinct differences:
Anxiety: Anxiety is a normal and common human emotion experienced in response to perceived threats or stressors. It is a natural response that prepares the body to deal with potential dangers or challenges. Occasional anxiety is a part of life and can even be helpful in certain situations, as it keeps us alert and focused. For example, feeling anxious before a job interview or a big exam is common and can motivate us to prepare adequately.
Anxiety Disorders: Anxiety disorders, on the other hand, go beyond the normal experience of anxiety. They involve excessive, persistent, and uncontrollable worry or fear that significantly impairs a person's ability to function in daily life. These disorders are more intense and chronic, causing distress that can be overwhelming and interfere with various aspects of life, such as work, school, relationships, and social activities.
Physiology of anxiety:
The physiology of anxiety involves a complex interplay between the brain, nervous system, and various neurotransmitters. When a person encounters a perceived threat or stressful situation, the body initiates a series of physiological responses to prepare for a fight-or-flight response, which we will examine in detail later on. This response is an ancient survival mechanism that helped our ancestors react quickly to immediate dangers. In the modern world, however, this response can sometimes become overactive, leading to anxiety disorders. Let's explore the key physiological components of anxiety:
1. The Brain's Role: The amygdala, a small almond-shaped structure deep within the brain, plays a crucial role in processing emotions, including fear and anxiety. When a potential threat is detected, the amygdala signals the hypothalamus to activate the sympathetic nervous system.
2. Activation of the Sympathetic Nervous System (SNS): The SNS triggers the release of stress hormones, such as adrenaline and noradrenaline (also known as epinephrine and norepinephrine). These hormones prepare the body for action by increasing heart rate, constricting blood vessels, and raising blood pressure, among other physiological changes.
3. Fight-or-Flight Response: The activation of the SNS initiates the "fight-or-flight" response, preparing the body to either confront the threat or flee from it. This response can be adaptive in acute stress situations but can become problematic when activated inappropriately or excessively.
4. Activation of the Hypothalamic-Pituitary-Adrenal (HPA) Axis: In response to stress, the hypothalamus releases corticotropin-releasing hormone (CRH), which stimulates the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH, in turn, triggers the adrenal glands to release cortisol, the primary stress hormone. Cortisol helps regulate various physiological processes during the stress response.
5. The Role of Neurotransmitters: Several neurotransmitters play a role in anxiety, with two key ones being serotonin and gamma-aminobutyric acid (GABA). Serotonin is involved in regulating mood and emotions, and imbalances in serotonin levels have been linked to anxiety disorders. GABA, on the other hand, acts as an inhibitory neurotransmitter, reducing neuronal activity and promoting relaxation. Deficits in GABA function have been associated with anxiety disorders.
6. The Role of the Prefrontal Cortex: The prefrontal cortex, the brain's executive center, is responsible for higher-order cognitive functions, such as decision-making and impulse control. In anxiety disorders, there can be an imbalance between the amygdala (responsible for emotional responses) and the prefrontal cortex, leading to difficulties in regulating fear and anxiety.
7. Chronic Activation and Chronic Stress: In chronic anxiety, the physiological response of the body can become persistently activated. Over time, chronic stress and elevated cortisol levels can lead to various health issues, including cardiovascular problems, weakened immune function, and other physical and psychological symptoms.
Fight or flight response
The fight-or-flight response, also known as the acute stress response, is a physiological reaction that occurs in response to a perceived threat or stressor. It is a fundamental survival mechanism that prepares the body to either confront the threat (fight) or escape from it (flight). The fight-or-flight response is an ancient evolutionary adaptation that allowed our ancestors to respond quickly to immediate dangers, such as encountering predators.
When the brain perceives a threat, it sends signals to various parts of the body to initiate the fight-or-flight response. Here's a step-by-step explanation of the process:
Perception of Threat: The process begins with the amygdala, a small almond-shaped structure in the brain responsible for processing emotions, particularly fear and anxiety. The amygdala detects potential threats in the environment or perceived dangers based on past experiences.
Activation of the Sympathetic Nervous System (SNS): Once the amygdala identifies a threat, it signals the hypothalamus, a region of the brain that controls various bodily functions, including the autonomic nervous system. The hypothalamus activates the sympathetic nervous system (SNS), one of the two divisions of the autonomic nervous system.
Release of Stress Hormones: When the SNS is activated, it triggers the release of stress hormones, such as adrenaline (epinephrine) and noradrenaline (norepinephrine), from the adrenal glands. These hormones flood the bloodstream, preparing the body for action.
Physiological Changes: The release of adrenaline and noradrenaline leads to several physiological changes aimed at enhancing physical abilities and preparing the body to deal with the threat:
Increased Heart Rate: The heart rate increases, pumping more blood to deliver oxygen and nutrients to muscles and vital organs.
Dilation of Pupils: The pupils dilate to improve visual acuity, allowing the person to better assess the environment.
Bronchial Dilation: The airways widen, facilitating rapid breathing to supply oxygen to the body.
Increased Blood Flow to Muscles: Blood flow is redirected from non-essential organs (e.g., digestive system) to the muscles, providing them with additional energy.
Heightened Awareness: The senses become more acute, making the person hyper-alert to potential dangers.
Suppression of Non-Essential Functions: Non-essential bodily functions, such as digestion, may be temporarily suppressed to conserve energy for the immediate threat.
5. Fight or Flight Decision: The physiological changes prepare the individual to either confront the threat and fight back or to flee from the danger. The response is determined by a combination of factors, including the nature of the threat, the individual's past experiences, and their assessment of their ability to cope with the situation.
6. Return to Homeostasis: Once the threat is perceived as no longer present, the parasympathetic nervous system, the other division of the autonomic nervous system, kicks in to counteract the effects of the fight-or-flight response. This allows the body to return to its normal state of homeostasis and rest.
The fight-or-flight response is a rapid and automatic physiological reaction that prepares the body to respond to potential threats. While this response is essential for survival in dangerous situations, chronic or excessive activation of the fight-or-flight response can contribute to stress-related health problems. Understanding this response can help individuals manage stress and anxiety more effectively and promote overall well-being.
In conclusion, anxiety is a normal emotional response to stress or perceived threats, while anxiety disorders involve intense and persistent anxiety that significantly disrupts an individual's life. When anxiety becomes chronic, excessive, and impacts daily functioning, it may indicate the presence of an anxiety disorder that can benefit from professional evaluation and treatment. If you or someone you know is experiencing severe anxiety or symptoms of an anxiety disorder, please reach out to book an appointment at The Psychology Alley to see a psychologist in Surry Hills if you would like anxiety treatment.
