When you or a loved one are experiencing depression, it can feel like a challenging puzzle to solve. In this state, all you want to do is feel happier; it can be overwhelming not to have any answers and not know if you will ever get better. Depression is the 4th leading cause of disability worldwide and can result in loss of life, increased chances of contracting other illnesses, substance abuse, and lost work time. Scientists are still hard at work uncovering new information about this complicated disease. Understanding the mechanisms behind depression can help provide comfort and confidence in moving forward and selecting the right treatment.
Getting to Know Neurotransmitters
In order to understand depression, it is crucial to know a little about neurotransmitters. These chemicals send signals throughout your nervous system and body – neurotransmitters are like the hormones of your brain. While they exist in other areas of the body, neurotransmitters are most common in your central nervous system and are implicated in a wide variety of brain functions beyond emotional regulation, such as: thought formation, movement, reward response, fight-or-flight reactions, sleep, and many more. The neurotransmitters implicated in depression are dopamine, norepinephrine, glutamate and brain-derived neurotrophic factor, although serotonin is the neurotransmitter most commonly implicated in both the development of depression and in its treatment.
Serotonin – Your Happy Brain Chemical
The main neurotransmitter implicated in depression is serotonin and this chemical is a target for many antidepressant medications. Patients with depression have lower levels of serotonin in their brain and nervous system , though 90% of serotonin is produced in the digestive tract. Depletion of tryptophan, the chemical precursor to serotonin, causes relapse of depression in those who previously had remission.
Although serotonin is responsible for many actions, from heart function to sleep to gut movements, its role in mood is undeniable and yet undeniably complex. While scientists are constantly uncovering new information on depression, they have found that most treatments for major depressive disorder tend to affect serotonin breakdown and/or processing in some way. Current depression therapies target or increase these neurotransmitters in attempt to rebalance the chemical dysfunction that occurs in the brain during depression, although there is more work to do to help patients.
What Causes Depression?
There are many factors than can contribute to depression. Stress can be a significant factor in depression as chronically high levels of stress hormones can change the very structure of our brains; these changes can affect the delicate serotonin balance simply by shrinking the prefrontal cortex, the area of the brain responsible for our behavior and personality.  Other contributors to depression, such as early life stress, learned helplessness, repeated victimization and social isolation have been studied and verified in rodents and humans to change brain functionality and therefore, change mood.
Those who understand the impact of this disorder know that it is a powerful, invisible disease and people should feel no shame or resistance in seeking treatment.. There are many different treatments for depression, and dTMS (deep TMS) has been shown to be an effective option to give relief. Whichever treatment is chosen, depression is a treatable condition. Hopefully a deeper understanding of its causes can help de-stigmatize this disorder and remove barriers to treatment.
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