The Upward Spiral

The structure of the human brain explains how people fall into deep depressions.

If you tell a friend that you’re feeling depressed, he’ll probably assume there must be an external cause for your mood and ask “why?” But if you want to understand the dark spiral of depression, you need to start somewhere else entirely.

To begin with, you can divide the brain into the feeling brain and the thinking brain.

The feeling brain is the limbic system. Also known as the reptile brain, it’s composed of several older brain sections. These areas are responsible for making people feel emotions – particularly stress and anxiety.

Then there’s the thinking part of the brain or the prefrontal cortex. It’s located behind the forehead and is the newest development in the evolution of the human brain. In addition to playing a key role in determining human intelligence, it regulates the limbic system.

In normal conditions, the prefrontal cortex lets us think in an abstract way about negative emotions like guilt, shame or worry, and this creates some distance that helps us process them. When a person becomes depressed, the prefrontal cortex can no longer do its job properly, and emotions start getting out of control, triggering greater stress and anxiety.

So, a malfunctioning prefrontal cortex leads to depression and a downward spiral.

Just consider the author, who has a tendency toward loneliness, especially when he spends all day writing. He could make plans to meet a friend after work, but planning causes him stress. The worse he feels because of his loneliness, the harder it is for him to make plans, which only locks him deeper into the downward spiral.

In the worst case, such downward spirals can cause chronic depression, but the factors triggering them vary from person to person. So, while the author requires social contact to stave off a vicious circle of low moods, a friend of his falls into a downward spiral when she doesn’t get enough exercise.

That being said, for many people, anxiety and worry are the main factors that cause a downward spiral. In the next blink, you’ll learn more about these primary culprits.