Fight-or-Flight Response

Definition

The fight-or-flight response is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It is a survival mechanism that prepares the body to fight or flee from a perceived threat or stressful situation.

5 Must Know Facts For Your Next Test

1. The fight-or-flight response is triggered by the sympathetic nervous system, which prepares the body for intense physical activity.
2. During the fight-or-flight response, the adrenal glands release hormones like adrenaline and cortisol to increase heart rate, blood pressure, and glucose levels.
3. The hypothalamus plays a key role in the fight-or-flight response by activating the sympathetic nervous system and the HPA axis.
4. Chronic activation of the fight-or-flight response can lead to negative health effects like high blood pressure, weakened immune system, and mental health issues.
5. Relaxation techniques like deep breathing, meditation, and exercise can help counteract the physiological effects of the fight-or-flight response.

Review Questions

• Describe the role of the sympathetic nervous system in the fight-or-flight response.
  • The sympathetic nervous system is the primary driver of the fight-or-flight response. When the body perceives a threat, the sympathetic nervous system is activated, triggering a cascade of physiological changes. This includes increasing heart rate, blood pressure, and respiration to prepare the body for intense physical activity. The sympathetic nervous system also stimulates the adrenal glands to release hormones like adrenaline and cortisol, further amplifying the body's stress response.
• Explain the role of the hypothalamus-pituitary-adrenal (HPA) axis in regulating the fight-or-flight response.
  • The hypothalamus-pituitary-adrenal (HPA) axis is a complex neuroendocrine system that plays a crucial role in the body's stress response, including the fight-or-flight reaction. The hypothalamus senses a threat and activates the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete cortisol, a hormone that helps the body mobilize energy and cope with the stressful situation. This HPA axis feedback loop ensures the fight-or-flight response is appropriately regulated to maintain homeostasis.
• Discuss the potential long-term health consequences of chronic activation of the fight-or-flight response.
  • Prolonged or frequent activation of the fight-or-flight response can have negative impacts on overall health. Chronic stress and elevated levels of hormones like cortisol can lead to high blood pressure, weakened immune function, and increased risk of mental health issues like anxiety and depression. Additionally, the constant state of physiological arousal can contribute to the development of conditions such as heart disease, diabetes, and gastrointestinal problems. Implementing stress management techniques and lifestyle changes to counteract the fight-or-flight response is essential for maintaining long-term health and well-being.

Related terms

Sympathetic Nervous System: The part of the autonomic nervous system responsible for the body's rapid response to stressful or dangerous situations, triggering the fight-or-flight response.

Adrenal Glands: Two small endocrine glands that sit atop the kidneys and release hormones like adrenaline and cortisol during the fight-or-flight response.

Hypothalamus-Pituitary-Adrenal (HPA) Axis: The complex interaction between the hypothalamus, pituitary gland, and adrenal glands that regulates the body's response to stress, including the fight-or-flight reaction.