Depression is a serious mental illness and, if left untreated, can have terrible effects on the sufferer’s overall health and mental well being. Many people know that depression changes the way a person sees themselves and the world around them, but they may not know that depression actually changes the physiology of the brain. Untreated, or especially hidden depression, can create long lasting changes inside of the brain and can bring about other mental illnesses such as generalized anxiety disorder and suicidal thoughts and behaviors. The aim of this article is to examine 7 ways that hidden and how untreated depression can change the brain.
1. Risky Behaviors
Depression alone can cause the sufferer to engage in risky behaviors, or at least have an indifferent approach to looking at certain situations. Untreated or hidden depression can cause an extra large spike in this line of thinking and acting. Without understanding where the indifference is coming from the sufferer might be more apt to adopt the use of drugs or alcohol to combat the side effects from their hidden depression. This in turn can cause them to be at a higher risk of dependency and addiction which not only changes how the brain works but how the entire body works as well.
2. Suicidal Thoughts
According to Scientific America, two-thirds of those that commit suicide were first afflicted by depression. This may be due to the fact that those with depression have a lower amount of the chemical receptors for GABA within their frontopolar cortex. GABA inhibits neuron activity, it slows down the activity within the brain and having fewer receptors doesn’t allow it to do its job properly. Within the Canadian study referenced by Scientific America it was found that there was a methyl group attached to the GABA-A receptor. This causes the receptors to essentially be invisible to GABA and unable to receive the input necessary to slow the neural activity. While the scientists aren’t entirely sure as to why this abnormality occurs, they have narrowed it down to being influenced by something within the person’s environment, and that it is not a mutation occurring organically within the brain itself.
3. Shrinking of the Hippocampus
The hippocampus is the part of the brain that stores memories of events and responds to stress hormones that are released into our bloodstream. Depression can put undo stress on the body and mind causing the hippocampus to shrink. This can cause the area of the brain to be less effective in dealing with stressors and can slow down the rate at which the dentate gyrus creates new brain cells.
4. Shrinking of the Prefrontal Cortex
The prefrontal cortex is an important part of the brain that controls emotional regulation, decision making, and helps with memory. Depression can shrink this area of the brain as well, which can lead to being emotionally unregulated and can in turn cause the sufferer to have emotional outbursts. It also may effect how the person remembers things and can cause them to become stressed and indecisive or have trouble taking the time to think out all possibilities before making large decisions in life.
5. Enlarged Amygdala
The amygdala is where the brain stores emotional memories and becomes overactive in those that suffer from depression and post-traumatic stress disorder. Having an over active amygdala can lead to sleep disturbances, many of those suffering from depression report insomnia or wanting to sleep non-stop, and issues with physical activity. This can also lead to abnormal hormone secretions that can reek havoc on other areas of the body and systems that keep a person’s body up and running.
6. Changes in Cortisol Levels
Every person’s brain secretes cortisol. The normal elevations of the cortisol are highest during the morning and diminish at night, but for someone with depression the levels vary significantly. With depression, the level of cortisol is always high, no matter what time of day, and can lead to a lowered immune system as well as issues with memory and learning. Cortisol is known as the “stress hormone” and heightened levels of it can lead to depression as well as a host of other mental illnesses.
7. A Decrease in Serotonin
It has long been believed that there is a link between decreased serotonin inside of the brain and depression. One study found that participants who were not at risk for depression who ate a diet to intentionally manipulate the amino acid tryptophan did not have any marked difference in their mood. Those that had a history of depression exhibited short bursts of depressive episodes on the same diet. This along with the fact that medications known as SSRIs are used in the treatment of depression help strengthen the hypothesis that the two are linked in some way. It isn’t known if the lower levels of serotonin are what contribute to depression or if they are there because of the depression.
While all of these things are found within the brains of those that suffer from depression, it is important to note that untreated or hidden depression can cause these effects to last weeks, months, years or even over an entire lifetime. The longer depression is hidden and untreated, the worse these symptoms can become. Leaving depression to chance can cause the sufferer to lose connection with family and friends, can cause them to isolate themselves from others, and can cause any number of other severe mental illnesses. The comorbidity of depression and anxiety is high, as it is between depression and PTSD, and prolonged exposure to the stressors from these conditions can have an even larger list of side effects and brain changes.
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