What is the Origin of Human Physiology Stress?

The foundation of this term lies in the pioneering work of Hans Selye, who introduced the concept of the General Adaptation Syndrome (GAS) in the mid-20th century, describing the three stages of alarm, resistance, and exhaustion. The physiological aspect emphasizes the measurable, systemic changes—such as increased heart rate, elevated blood pressure, and glucocorticoid release—that constitute the body's reaction.

What is the Mechanism of Human Physiology Stress?

The initial response is rapid, involving the sympathetic nervous system and the release of catecholamines like epinephrine and norepinephrine from the adrenal medulla. For sustained stressors, the slower-acting HPA axis is activated, releasing cortisol from the adrenal cortex. These hormones act systemically to mobilize energy resources, suppress non-essential functions like digestion and reproduction, and modulate immune activity, all in an effort to enhance immediate coping capacity.

Human Physiology Stress ∞ Area

Human Physiology Stress

Meaning

Human physiology stress is the comprehensive, non-specific biological response mounted by the body to any demand, whether physical, emotional, or environmental, that perturbs its homeostatic balance. This response involves a coordinated activation of the nervous, endocrine, and immune systems, designed to restore equilibrium and ensure survival. Clinically, understanding this response is key to differentiating adaptive, acute stress from pathological, chronic allostatic overload.