What is Anxiety?

Anxiety is a thief. It steals your time and attention. It locks you in cycles of sleeplessness, rumination, worry, and uncertainty. But what is anxiety, exactly? And why does our brain do this to us?

One of the brain’s core functions is detecting and managing threats. For much of human history, that meant staying alert for immediate physical dangers—like a lion hiding in the bushes. If a potential threat was detected (or even suspected), a network of brain regions, including the amygdala, rapidly activated the body’s stress response. Stress hormones such as adrenaline and cortisol were released, increasing heart rate and breathing, sharpening attention, and redirecting blood flow toward the muscles to prepare for fighting or fleeing. At the same time, activity in parts of the brain involved in deliberation, planning, and nuanced judgment—particularly regions of the prefrontal cortex—was reduced. After all, careful reasoning isn’t especially useful if you believe you’re about to be eaten!

Don’t think, our brains screamed. Run!

This threat-response system—hypervigilance paired with rapid, reflexive action—helped our species survive. Which is great! The problem is that while our environment has changed dramatically, our brains have not fully caught up. Even though the biggest threats most of us face on a day-to-day basis involve things like sales presentations, tinder dates, and Thanksgiving dinner with our in-laws, our brains still tend to treat these things like they’re lions hiding in the bushes.

But let’s not be too mad at our poor, confused brains. They do what they do because they learned long ago that playing it safe beats becoming someone’s lunch. Better to be constantly on the lookout for lions than take a chance of missing one. The downside of this bias toward safety is that it  leaves us consumed with worry and prone to panic and exhaustion as we react again and again to threats that exist largely in our minds.

For some people, this system is especially sensitive and persistent. In any given year, roughly 19% of adults in the United States meet criteria for an anxiety disorder, such as generalized anxiety disorder, social anxiety disorder, panic disorder, or specific phobias. Closely related—but classified separately—is obsessive-compulsive disorder, which also involves threat detection and attempts to neutralize perceived danger.

So what do you to about it? Well, that’s where treatment comes in.