The HPA Axis, the Stress Response, and You: Countering Anxiety

What is the hypothalamic-pituitary-adrenal axis (HPA axis) and how does it create a stress response that triggers anxiety? Anxiety that comes up without any rhyme or reason is frustrating and a sign of the HPA axis in action. You can be feeling relaxed and calm doing something you enjoy, and yet somehow your body still starts telling you it's time to feel anxious. When this happens, it can be really difficult to cope because there isn't anything you can identify that is making you feel this way. In these times, understanding the physiological process involved in the experience of anxiety can help you relax through the experience and reduce your anxiety, so today I'm going to discuss the HPA axis and its role in anxiety. 

What Is the HPA Axis?

The HPA axis is comprised of the hypothalamus, the pituitary gland, and the adrenal gland. Signals are sent from the hypothalamus to the pituitary, and from the pituitary to the adrenals, resulting in the release of the aptly named "stress hormone": cortisol.

Cortisol is responsible for many regulatory functions in the body, but when we are feeling anxious it is in part because cortisol has been released in the body to a greater degree than normal. This release of cortisol prepares the body to either escape from or engage with a threat, and so it produces increases in blood pressure and heart rate while also reducing blood flow for less important functions like digestion. These changes prompted by cortisol produce the majority of physical symptoms you may experience while anxious -- feeling like your heart is beating too fast, stomach pain or nausea, feeling light-headed, or like your vision is different than normal ("Physical Side Effects of Anxiety in the Body"). When the threat is gone, the body begins regulating itself, reducing circulating cortisol and the physical sensations you feel during anxiety. 

With anxiety, the HPA axis' regulatory process can be disrupted, leading to unnecessary increases in cortisol or preventing the body from reducing cortisol secretion after a threat has been dealt with. Consequently, when a threat is encountered, anxiety makes the body think it has to be ready for a threat even after that threat is no longer there. This is one explanation for why you may feel anxious even after you've faced something you were afraid of -- it just takes time for the body to recognize that it doesn't have to be on high alert anymore. 

The Stress Response and You 

So, how does this information about the HPA axis help you with your anxiety? Here's the key takeaway: this information provides you with a story to tell yourself when you're experiencing anxiety that allows you to counter your anxious thoughts. If you get anxious and your body feels different, you can now say, "Okay, I'm feeling really anxious and my heart is racing. That means my body is releasing extra cortisol right now so I can protect myself. One way it is protecting me is by increasing my heart rate so I can run away easily." 

Having this explanation ready to go when you feel anxious is a fantastic tool for breaking down your anxious thoughts and feelings, and it can help you regulate your body and reduce anxiety more quickly.

Anxiety often causes the most trouble when you engage with your anxious thoughts and believe the story they tell -- that something is horribly wrong and you can't do anything about it. Understanding that your anxiety is the result of a natural process in your body that is meant to protect you breaks down those anxious thoughts, and allows you to recover from anxiety more quickly. Try using this explanation the next time you experience anxiety, and let me know what experiences you have with it. 

Sources

1. Watson, Stuart. "HPA Axis Function in Mood Disorders". Psychiatry. March 2009.