HPA Axis
Also known as: Hypothalamic-Pituitary-Adrenal Axis
The three-gland communication chain that manages your stress response — and the reason chronic stress can rewire your brain.
The hypothalamic-pituitary-adrenal axis — a communication chain between three glands that manages your stress response. When you perceive a threat, this system releases cortisol. In depression and chronic anxiety, the HPA axis can become stuck in 'on' mode, flooding the body with stress hormones even when there is no immediate threat.
How it works
Your hypothalamus, pituitary gland, and adrenal glands form a feedback loop that releases cortisol in response to stress. When this system is chronically activated, it can become dysregulated — either over-responding to small triggers or failing to respond when needed.
Think of it like
It's like a thermostat that's been stuck on 'high' for so long that it forgets what 'normal' temperature feels like.
What it feels like
You feel either constantly on edge or strangely flat — your stress dial has lost its sense of proportion.