How Depression Affects the Brain

June 12, 2020

Human beings may display or feel sadness and grief from time to time. Depression and associated symptoms can be (and are) very common amongst Americans. If one considers the rate of diagnosis for the various types of depressive disorders, nearly one hundred million individuals in the United States suffer from some form of depression. That is a staggering number.

What many do not realize about depression is that is isn’t just sadness or a case of “the blues.” As alluded to above, there are several different forms of depression which cause various symptoms and generally impact the population at different ages. Some types of depression are more common in teens and young adults, whereas some have a typical age of onset much later in life. Also, depression does not affect only individual emotional states. Depression also has an impact on the brain itself, and some of these impacts can be permanent if one’s depressive symptoms are not addressed.

What is depression?

Depression is a mood disorder that affects the way a person thinks, feels, and behaves. Depression and its associated illnesses cause feelings of sadness or hopelessness that can last for varying lengths of time, ranging from a few days to a few years.

Some people may only experience a case of depression once in their lives. Others, on the other hand, may have several severe episodes over their lifetime. This pervasive and more intense form of depression is known as a major depressive disorder. It is also sometimes referred to as clinical depression or major depression. The symptoms one experiences with major depressive disorder significantly interfere with their ability to function or complete daily activities such as school, work, and social events. They also impact mood and behavior as well as physical functions such as sleep and appetite. Major depressive disorder affects approximately fifteen million American adults and occurs in roughly one out of every eight teens.

How does depression affect the brain?

Everyone knows depression has an impact on people’s emotions and mood. However, it also has the potential to affect physical structures in the brain. These physical impacts range from inflammation and oxygen restriction to actual shrinkage of the brain. Three primary parts of the brain appear to be impacted or play a role in major depressive disorder. These include the hippocampus, amygdala, and the prefrontal cortex.

The hippocampus

The hippocampus is located near the center of the brain. This part of the brain is responsible for storing memories and regulating the production of the hormone cortisol. During times of physical and mental stress, the body releases cortisol. This release also occurs during times of depression. Problems arise when excessive amounts of cortisol are sent to the brain during a stressful event or during a time of chemical imbalance in the body.

In a healthy brain, brain cells (or neurons) are produced throughout one’s adult life. Production of neurons occurs in the dentate gyrus, which is part of the hippocampus. In people with major depressive disorder, the long-term exposure to increased cortisol levels can slow the production of new neurons and cause the existing neurons in the hippocampus to shrink, resulting in memory problems.

The prefrontal cortex

This part of the brain is located at the very front of the brain. The prefrontal cortex is responsible for regulating emotions, making decisions, and forming memories. When the body produces excess cortisol, the prefrontal cortex also appears to shrink.

The amygdala

The amygdala is the part of the brain responsible for facilitating emotional responses such as pleasure and fear. In people who have a major depressive disorder, the amygdala becomes enlarged and more active. This increased activity occurs as a result of the constant exposure to high levels of cortisol. When the amygdala is enlarged and hyperactive (in conjunction with other abnormal activity occurring in other parts of the brain), it can result in disturbances in sleep and activity patterns. It can also cause the body to release irregular amounts of hormones and other chemicals in the body, which can lead to other medical complications.

Other areas of the brain that are thought to potentially experience size changes due to depressive episodes are the thalamus and the frontal cortex.

In addition to size and other changes, the brain can also become inflamed and suffer from oxygen deprivation due to depressive symptoms.

Brain inflammation

Research has shown new links between inflammation of the brain and depression. However, it is still not clear whether depression causes inflammation or the opposite. Brain inflammation during depression has been linked to the amount of time the person is depressed. The longer the depressive episode (or series of depressive episodes), the more significant the levels of inflammation. Consequently, considerable inflammation of the brain is highly likely if one suffers from a persistent depressive disorder.

Inflammation within the brain can cause the death of brain cells leading to a variety of health-related and neurological complications, including brain shrinkage, decreased neurotransmitter functionality, and a reduction in neuroplasticity (or the ability of the brain to change as a person ages). These functions and structural changes can affect brain development, learning, memory, and overall mood.

Oxygen restriction

Depression has also been linked to reduced oxygen levels in the body. When the brain does not get enough oxygen, it can cause inflammation, cellular change, or injury (of the cells within the brain) and brain cell death. Even short-term oxygen deprivation to the brain can cause confusion and memory difficulties, although these usually are temporary. With long term deprivation as can occur with depression, the changes may be irreversible.

How can treatment change the brain?

Research has shown that balancing the amount of cortisol and other chemicals in the brain can help to reverse the brain’s shrinking processes. Correcting these chemical imbalances can also help to reduce the symptoms of major depressive disorder while helping to treat memory challenges associated with the changing sizes of various brain structures.

Several medications commonly prescribed for depression (and related illnesses such as anxiety) can help mitigate the adverse effects of depression on the brain. These include:

  • Selective serotonin uptake inhibitors (SSRIs)-These drugs help alleviate the symptoms of major depressive disorder by changing the serotonin levels in the brain.
  • Serotonin-norepinephrine reuptake inhibitors (SNRIs) and tricyclic antidepressants- when used together, these medications can help to alleviate symptoms by altering both serotonin and norepinephrine levels in the brain. These chemicals are responsible for boosting mood and elevating energy levels.
  • Norepinephrine-dopamine reuptake inhibitors (NDRIs)- These help those with major depressive disorder by stimulating the production of norepinephrine and dopamine in the brain.
  • Monoamine oxidase inhibitors (MAOIs)- These are drugs that help ease major depressive disorder symptoms by increasing the amount of norepinephrine, serotonin, and dopamine in the brain. They are also known to help improve brain cell communication.

In addition to therapy, there are other things you can do to help reduce the effects of depression on the brain. They include:

  • Following a healthy diet and staying active- Healthy foods and routine activity can help to stimulate brain cells and strengthen communication between the cells of the brain.
  • Sleep-Sleep is essential for all of the restorative functions of the body. Where the brain is concerned, sleeping hours are the time where your brain works to grown and repair cells.
  • Avoid alcohol, and non-prescription drugs-research has shown both substances are known to destroy and inhibit the function of brain cells.
  • Reduce stress levels- the best way to prevent brain changes associated with depression (and to reduce the possibility of depressive onset) is to reduce stress. Considerable research links psychological stress to the emergence of depressive symptoms in many forms of depression.

Therapy for depression and brain changes

Research also indicates that psychotherapy can alter the brain structure and help to relieve many symptoms associated with major depressive disorder. Specifically, psychotherapy (or talk therapy) appears to help strengthen the function of the prefrontal cortex. There are several different types of psychotherapy, including dialectical behavior therapy (DBT) and cognitive-behavioral therapy (CBT). These therapies are designed to help someone identify triggers or events which may lead to feelings of depression. Additionally, treatment is guided towards developing new and positive belief systems, developing new coping strategies (use to deal with adverse events and emotions), and to identify detrimental beliefs that they hold, which can lead to depressive symptoms. Psychotherapy should be geared towards the individual and their specific needs and symptoms.

Psychotherapy can take place in a variety of setting depending on what is necessary and the most comfortable for the person. For many teens, individual and group therapy settings tend to work best. Individual therapy is helpful for someone who experiences only mild symptoms or form whom depression is not pervasive in their day to day lives. These treatment sessions can take place in a private therapy office while your teen continues to live at home and continue with their normal activities.

Solo - Depression - Hillcrest

For other teens who have been experiencing depression symptoms for a long time, a residential treatment program may be a better choice. California residential programs like Hillcrest Adolescent Treatment Center are suggested if your teen has been struggling with depression, are unable to keep themselves safe, or are experiencing particularly severe symptoms.

Depression is a severe and debilitating illness that is so much more than people consider it to be. When people think of depression, they commonly think of feelings of sadness or someone being upset. Depression can have physical and lasting impacts on the body, which can permanently change how the brain and other body systems function. If your teen is experiencing severe and persistent depression, don’t wait to seek treatment. Depression and its associated impacts are treatable; however, the earlier treatment is sought, the more likely your teen is to see successful results. If your son or daughter is struggling with depression, contact Hillcrest Adolescent Treatment Center today.