taistelupakoreaktio

Taistelupakoreaktio, often translated as fight-or-flight response, is an involuntary physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It is a fundamental survival mechanism that prepares the body to either confront the danger or escape from it. This response is orchestrated by the sympathetic nervous system, a division of the autonomic nervous system.

When the brain detects a threat, it signals the adrenal glands to release hormones, primarily adrenaline and cortisol. These hormones trigger a cascade of physiological changes. The heart rate increases, blood pressure rises, and blood is redirected from non-essential functions like digestion to the muscles, providing them with more oxygen and energy. Respiration rate also increases, further enhancing oxygen intake. Pupils dilate to improve vision, and the body may begin to sweat to regulate temperature during intense activity.

These changes collectively equip an individual with heightened alertness, strength, and speed, enabling them to react swiftly to the perceived danger. Once the threat has passed and the body perceives safety, the parasympathetic nervous system takes over, initiating the "rest and digest" response to calm the body and return it to its normal state. While evolutionarily advantageous for immediate physical threats, chronic activation of the fight-or-flight response due to modern stressors can have negative long-term health consequences.