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mechanism of anxiety — learn to fly tutorial


That auto-shitter that stresses you heavily, pun intended. You may remember it from such films as turning basically everything to mental catch 22 or overlapping worrying circle. Today we are talking about your personal control freak trainer, inner darkness pimp, and panic and depression easter egg.


We kinda know that anxiety happens in the brain. We also kinda know-how. Kinda. Let’s call it the mechanism of anxiety. I’ll try to present it in a few brain steps a bit later on.

First, let’s talk about recent science endeavors regarding this dun dun dun — mental disorder.

Anxiety cells

Neuroscientists have announced they’ve identified the brain cells associated with anxiety in mice.

This was a collaboration of researchers from UC-San Francisco and Columbia University’s Irving Medical Center. Mazen Kheirbek, Ph.D., an assistant professor of psychiatry at UCSF was the senior researcher on this study and together with his colleagues has presented the results in the journal Neuron.

These “anxiety cells” are where the emotion is stored.

Researchers started their search with the hippocampus, a part of the brain primarily known to be associated with anxiety. It’s also involved in emotion and memory.

Researchers placed miniaturized microscopes in the brains of mice and then put the rodents in stressful situations.

Mice are afraid of wide-open spaces, where they can easily be spotted and scooped up by a predator. So the scientists took these newly equipped mice and placed them inside mazes where some of the corridors terminate in an open space.

What we found is that these cells became more active whenever the animal went into an area that elicits anxiety, Kheirbek said.

The reason researchers call them “anxiety cells” is, these special neurons only fire when the animal confronts a situation that’s scary.

Although this showed that such cells are involved with anxiety, it didn’t prove that the feeling originated with them.

The research, however, is at an early stage and lab findings in animals don’t always pan out in humans. The discovery of anxiety cells is just the latest example of the tremendous progress scientists have made toward understanding how anxiety works in the brain.

Let’s see what we know by far about the mechanism of anxiety in our brains.


STEP 1: This is Sparta!

When something frightens you, your amygdalae, two almond-shaped clusters of neurons nestled deep within your brain, tag the event as remarkable to prepare you for similar happenings in the future. Whether the threat is real or perceived, the alert mechanism seems to work the same way.

Even before you are conscious of a feeling of fear, your amygdala has sent an emergency alert to its neighbor, the hypothalamus.

The hypothalamus will then inform the rest of your body by stimulating nerve endings to release two hormones that also act as neurotransmitters: epinephrine, also known as adrenaline, and norepinephrine. Adrenaline and norepinephrine put your body into fight or flight mode: They increase heart rate, dilate arteries to accelerate delivery of blood to muscles, slow down the digestive system to conserve body energy, and nudge the liver to release glucose for more energy.

STEP 2: Show must go on.

The activated hypothalamus’ neurons then release other hormones to fully prep your body for action — vasopressin, to constrict arteries and increase blood pressure to deliver blood supply to your muscles, and oxytocin, which some scientists believe suppresses the hormonal response to stress. The hypothalamus also secretes a third hormone, corticotropin-releasing factor (CRF), which then activates the pituitary gland, a pea-sized organ located at the bottom of the hypothalamus.

STEP 3: Dracarys!

Activated by CRF, the pituitary gland secretes adrenocorticotropic hormone (ACTH). ACTH courses from the brain to the adrenal glands, located down by the kidneys, and prompts them to throw more hormones into the mix—more adrenaline to stimulate the heart rate, and cortisol, a steroid that increases the liver’s production of glucose, which your body needs a lot of to make fast and precise moves. The pituitary gland will continuously produce ACTH to fuel the adrenal glands’ adrenaline and cortisol secretion until the hypothalamus shuts off its CRF release.

STEP 4: Everything is 10-4.

When the stressful situation comes to an end, as most eventually do, the hormonal response initiated by your brain will also stop. As cortisol builds up in the body, it will travel back to the hypothalamus, passing through the blood-brain barrier that separates the brain and cerebrospinal fluid from the blood circulating in your body. Cortisol will inform the hypothalamus to shut off the cascading CRF release system and stop the cycle.

STEP 5: Member?

Cortisol and adrenaline help the brain remember particularly nerve-racking moments for future encounters. But if stressful events happen too often, this biochemical cycle can cause detrimental effects. When cortisol is perpetually produced, roaming around the body and penetrating the blood-brain barrier in constantly elevated numbers, the hippocampus may atrophy or shrink, affecting your ability to learn new information and form memories.

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