The Human Brain and it's interactions with Anxiety and Depression

Posted on June 2, 2025 by Amanda Hill, LMHC, NCC, BCC

Mental health therapists today are seeing more individuals in need of counseling services for anxiety and depression than any other mental health disorders. These two disorders affect millions of individuals each year and both need to be understood from more than a mental health perspective in order to be effectively treated. 

Anxiety and depression are not just emotional disturbances but are rooted in tangible changes in the brain.When treating these individuals it’s extremely important for therapists to make note of the physical aspects of his/her client’s health while also treating the individual from a psychological standpoint. This includes more in depth education on the brain and its functions, emphasizing how those aspects of our biology also need attention in order for one to achieve the full healing and happiness that they so desire. 

An individual who seeks out therapeutic treatment for anxiety and/or depression may be viewed as someone incapable of managing emotional and behavioral symptoms, but scientific research has actually revealed that both disorders are linked to profound changes in brain structure and function, which play an important role in how one functions in their day to day life.

One of the most consistently observed changes in the brains of individuals with anxiety and depression is increased activity in the amygdala - a small, almond shaped structure in the brain that plays a central role in processing emotions, especially fear and worry. The amygdala tends to be more hyperactive in those who have with anxiety disorders. This contributes to an exaggerated fear response, and with this heightened state of alertness it also feeds into more persistent worry, irritability, and difficulty concentrating.

 

The amygdala also plays a significant role in depression, with research showing it to be more active in depressed individual’s brains than in those who do not struggle with the same disorder. Depression disrupts the ability for the brain to regulate emotions - particularly when repeatedly exposed to negative events in life. This contributes to a person’s tendency to ruminate on negative thoughts and experiences, believing that they don’t have control over their own emotional regulation, which causes them to feel helpless when they so desperately need to feel in control. 

The hippocampus (which is critical for memory and spatial orientation) is another part of the brain that is also significantly affected by anxiety and depression. Studies have shown that individuals with chronic depression exhibit reduced volume in this region of the brain due to prolonged exposure to the stress hormones cortisol, which has long lasting negative effects over extended periods of time. Individuals who are suffering with post-traumatic stress disorder (PTSD) are especially noted to have shrinkage in the hippocampus. This reduction in volume impairs the brain’s ability to distinguish between past and present threats, which then contributes to flashbacks and intrusive memories. Ongoing studies are additionally showing dysfunction associated with cognitive symptoms such as poor memory, reduced attention span, and difficulty making decisions.

 

All of anxiety and depressions’s symptoms are negatively affected by changes in our prefrontal cortex, which is located in the forefront of your brain. The prefrontal cortex is responsible for higher-order cognitive processes such as making “smart” decisions, managing impulses, and regulating emotional responses. Decreased activity in this area of the brain results in poor emotional responses, making it more difficult for individuals to manage their stress effectively.

Imbalances in key neurotransmitters of the brain, such as serotonin, dopamine, norepinephrine and GABA are also being studied in those with anxiety and/or depression, due to their involvement in mood regulation and emotional processing. Serotonin affects your mood, sleep and appetite. Dopamine, which is linked to reward and pleasure, contributes to the feeling of unhappiness and distress. Norepinephrine, which helps us stay alert, fuels hypervigilence (especially with those who are anxious). And GABA is found to be reduced in anxiety disorders, which leads to more anxious tendencies expressing themselves.

Lastly, it has been found that when we contract our muscles, they secrete chemicals and proteins into our bloodstream that are profoundly excellent for brain health - making us resilient to stress and protecting us from mental health disorders such as depression and anxiety. This means that simply by being active (walking, hiking, running, dancing, weightlifting, etc) our muscles are  manufacturing these “hope molecules” that then act as antidepressants within the body, ultimately giving us the strength and courage we need to push through each day, but with more bounce in our step. It’s like we have a pharmacy within our muscles, providing us with almost the equivalent to antidepressant medications! How much cooler can it get than that?

So how does this information tie into every day life? Well… when you become more educated about what’s going on in your brain and body when struggling with anxiety and/or depression, it allows you to truly understand how much control you have over your mental health, which is extremely freeing. Also, if I have learned anything from my 20 years of experience in the mental health field, it’s that those who are willing to put in the work (not just by attending therapy sessions, but also by staying physically active) are the ones who undoubtedly reach their goals at a faster pace. Attacking symptoms of mental health from all angles will get you to a state of healing a lot faster than just focusing one (therapy) or the other (physical fitness). 

My hope, as a mental health therapist, has always been to empower individuals to gain insight into themselves and learn effective coping strategies to help manage emotional distress. This opens the door to better relationships, the capacity for change, and resilience with the right supports. 

If you, or someone you know, is in need of support, Connections of Hope is a private practice open to assisting you in whatever ways you need. Reach out to us at www.connectionsofhope.com and we can help guide you from there.

Author: Amanda Hill, MA, LMHC, NCC, BCC