How Does Depression Evolve and How to End it?

Did proto-humans feel depression or sadness? The answer is affirmative. Why do people feel sadness? The reason behind it is pretty straightforward- it usually occurs when things do not turn out the way they were desired. A big part of the world lives and functions to satisfy our endless and different desires, yet our desires keep going. It is important to realize our numerous desires and methods of fulfilling them stem from our lack of understanding about the true nature of things. Not knowing how everything exists is the main cause of depression, desire, problem, and suffering in one’s life. For more info go here.

“Getting bad results makes me sad.”

“I am hungry, this makes me sad. Food makes me happy.”

“I had a paper cut, nothing is worse than this, I am so sad.”

According to research, humans experience the most sadness on Mondays, that is a no-brainer, right? Another instance of sadness is seasonal sadness/depression, the symptoms start in the fall and linger till the end of the winter each year. These symptoms typically resolve during the start of summer.

Symptoms may include; losing interest in activities that you used to enjoy, having low energy and feeling sluggish, feeling worthless, losing appetite, oversleeping, weight loss, weight gain, increased irritability, and the list goes on. How can someone tell when you are sad/depressed? When you have a slumped posture, when you walk slowly, a downturned mouth, droopy eyes, etc. Not only are these applicable to humans but also to animals.

And all of these series of complex emotions come from an extremely small part of the brain, the amygdala, which occupies only about 0.3 percent of the total volume of the brain. When depressed, the amygdala becomes overactive which causes disturbances in the sleeping pattern and an imbalance of key mood hormones, this particular area in the brain is distinctly attuned to the neurotransmitter serotonin (5-HT). 5-HT appears to be essential for crucial brain functions, such as emotions (anxiety, sadness, and fear), sleep, appetite, motor activity, and sensory processing. 

According to the analysis of Gerard Sanacora, Ph.D., MS, Rachel Katz, MD, BS, and John Krystal, MD, from Yale Medicine, neurotransmitters are crucial chemical messengers that facilitate between the cells in the brain. With billions of connections between the neurons, the brain is home to approximately a hundred neurotransmitters. While serotonin and norepinephrine have been commonly linked to depression, they may not be the sole culprits responsible for the symptoms. Instead, glutamate and GABA, two neurotransmitters that are predominantly found in the brain’s higher centers, are regarded as possible alternatives and play a significant role in regulating mood and emotions in humans. Glutamate is excitatory which causes neurons to fire more, whereas GABA is inhibitory that tends to shut them off. The loss of connections between nerve cells due to chronic stress and depression can lead to messy and inefficient communications in these circuits, thereby impairing mood and emotion regulation. Consequently, the loss of synaptic connections is believed to be a critical player in the biology of depression.

Scientists also tell that people with a particular genetic variation in the gene that codes for serotonin are more vulnerable to depression which is thought to be the cause of reduced serotonin production in the brain. 

However, depression may not always be the result of a chemical disproportion; brain scanning studies have discovered that individuals with depression seem to have a decreased amount of gray matter in various regions in their brains, for instance; the amygdala, the hippocampus, and the cingulate cortex. The gray matter is the region where most of the neuronal signaling occurs as this area dominantly consists of dendrites, synapses, neuronal cell bodies, and glia, hence, fluctuations in gray matter volume contribute to changes in emotions, memory, and decision-making. This shrinking of brain parts results in difficulty in managing emotions and taking care of oneself.

In accordance to other scientists, depression could also be the outcome of changed neuroplasticity; the ability of the brain to form and rearrange synaptic connections in response to intrinsic or extrinsic stimuli. 

Depression may also be linked to our immune system. Patients with high levels of cytokines which are small proteins that are crucial for the body's immune and inflammatory responses are more susceptible to depression, thus doctors prescribe anti-inflammatory medications to the patients.

Treating this condition with anti-depressants helps to increase the formation of new brain cells, improving neuroplasticity and increasing serotonin levels.

Even though, the research on ketamine dates back several decades, it is only recently that individuals with depression have started to use it. The signaling process of glutamate is interrupted by ketamine. Ketamine also causes the brain to produce more chemicals helping neurons to grow new connections, this helps the patients to better regulate their emotions. When taken in high doses, ketamine can lead to a disconnection between higher and lower brain areas resulting in a feeling of detachment from the external environment. Although ketamine can cause hallucinations and addiction, studies have shown that it has a higher rate of success (about 50% - 80%) compared to other methods of treatment. 

Here is a list links to free resources:

https://psychcentral.com/quizzes/ptsd-quiz

https://www.mayoclinic.org/diseases-conditions/post-traumatic-stress-disorder/diagnosis-treatment/drc-20355973

https://www.mayoclinic.org/diseases-conditions/post-traumatic-stress-disorder/symptoms-causes/syc-20355967

https://www.healthline.com/health/how-to-get-tested-for-ptsd#ptsd-tests

https://www.psychologytoday.com/us/tests/health/depression-test

https://www.healthline.com/health/depression/depression-screening#where-to-take-a-depression-exam

https://www.mayoclinic.org/diseases-conditions/depression/diagnosis-treatment/drc-20356013

Written by Jiana Sumaita.