Generalized anxiety disorder

Generalized anxiety disorder, or GAD for short, is a mental health condition characterized by prolonged and excessive anxiety about everyday situations, such as finances, relationships, or day-to-day tasks. This anxiety is often out of proportion to the actual situation and can cause significant distress in daily functioning.

Imagine you have a big presentation coming up at school. You’ve been preparing for days, your slides look amazing, and you’ve practiced your delivery more times than you can count. But when you finally stand in front of the class to speak, your brain’s fear circuit suddenly kicks in.

The amygdala, which is an almond-shaped structure buried deep in the temporal lobe,

recognizes this situation as a potential threat and sends excitatory signals to the hypothalamus. The hypothalamus then activates the sympathetic nervous system, setting off a chain of reactions in the body, including a fast heartbeat, rapid breathing, sweating, muscle tension, and a dry mouth.

Meanwhile, the locus coeruleus in the brainstem releases norepinephrine, which floods the amygdala, activating beta-adrenergic receptors and pushing it into a state of hyperarousal. Additionally, adrenal glands start pumping out corticosteroids, which are stress hormones that can increase activity in fear-related circuits, making you more sensitive to stressful situations.

All these changes represent a typical anxiety response. It is uncomfortable but temporary and appropriate to the situation.

Once it’s all over and the room fills with applause, that wave of anxiety finally starts to fade. Your brain begins to wind down, and this is when the ventromedial prefrontal cortex comes into play. This part of the cortex directly inhibits the amygdala using the inhibitory neurotransmitter called GABA, quieting its activity and calming the anxiety response. At the same time, the ventromedial prefrontal cortex stimulates the raphe nuclei to release serotonin, which helps indirectly calm the amygdala even further.

Another key player in the fear circuit is the hippocampus. It helps your brain figure out whether a situation is actually dangerous or just feels that way because of something you've experienced before.

Now, in generalized anxiety disorder, the usual brake system between the ventromedial prefrontal cortex and the amygdala isn’t working properly. There’s not enough GABA and serotonin to keep the amygdala calm, while the locus coeruleus is working overtime and flooding the amygdala with norepinephrine. This pushes the amygdala into a constant state of high alert, keeping a person stuck in a state of excessive and disproportionate anxiety, fear, or worry. On top of that, when stress sticks around for too long, the body keeps pumping out corticosteroids, which can, over time, cause atrophy of the hippocampus and further impair the ability to manage stress.