Mental Health ConditionsDepression
Explore This Topic

4 Ways Depression Affects Brain Health

4 Ways Depression Affects Brain Health
Giada Canu/Stocksy
By
Updated on May 13, 2025
by

It’s well-known that depression can take a toll on your mental health, but did you know it can affect other aspects of brain health, too?

“People with depression exhibit differences in their brain as revealed through neuroimaging,” says Avigail Lev, PsyD, a clinical psychologist with the Bay Area CBT Center in California. Research shows that, over time, these physical changes in the brain could lead to changes in the way the brain functions.

For instance, the changes that come with depression can make it harder for someone to focus on and complete their usual work-related or personal responsibilities; they may also affect a person’s memory, leading to additional stress or frustration in everyday life.

So, how exactly does depression change the brain? Here are four ways, according to experts.

1. Depression Can Cause Parts of the Brain to Shrink, Leading to Memory Problems

“Depression can take a toll on your memory, and this isn't just a matter of forgetfulness,” says Brent Nelson, MD, an adult interventional psychiatrist and chief medical information officer at PrairieCare, a division of Newport Healthcare in St. Cloud, Minnesota.

The issue with depression and memory is not so much memory loss but obstacles to storing, consolidating, and retrieving memories, says Dr. Lev.

The connection between memory problems and depression may be related to changes in the brain. The hippocampus, a part of the brain that can be altered by depression, is essential for forming memories, says Dr. Nelson. “Studies have found that the hippocampus can decrease in size and activity in those with long-standing depression,” he says.

Shrinkage of the hippocampus may be related to cortisol, a hormone released by the body in response to stress. “Chronic stress and elevated cortisol levels associated with depression can also contribute to hippocampal changes, resulting in memory effects,” says Nelson.

Research shows that the hippocampus is the part of the brain most exposed to high concentrations of cortisol. Long-term stress can lead neurons (brain cells) in the hippocampus to die, resulting in shrinkage of the hippocampus.

Researchers are still learning whether the body’s release of cortisol itself or dysregulation of the body’s release of cortisol is what leads the hippocampus to shrink.

2. Depression May Contribute to Inflammation, Which Can Harm Brain Health

“There’s good evidence that depression contributes to inflammation, and, in general, depressed people have greater levels of inflammation than nondepressed people,” says James C. Jackson, PsyD, the director of behavioral health at the ICU Recovery Center in Nashville, Tennessee.

One theory for why this happens is that stress may cause changes in the immune system. This may contribute to an increased inflammatory response from the central nervous system, which in turn might contribute to the development of depression.

Researchers don’t yet know exactly how the brain’s response to inflammation affects its networks. One hypothesis is that inflammation caused by chronic stress disrupts neural pathways (connected brain cells that send signals from one part of the brain to another), potentially contributing to depression.

“Inflammation is harmful for the brain and likely contributes to adverse effects,” says Dr. Jackson. But how much depression contributes to inflammation versus the other way around is still not known, he adds.

3. Depression May Change the Prefrontal Cortex, Which Can Make It Harder to Pay Attention and Concentrate

“Executive functions, such as planning, decision-making, and problem-solving, can also be impaired by depression, leading to difficulties in daily life and work,” says Nelson. “This is often due to dysfunction in the prefrontal cortex, a key brain region for executive functions.”

Changes to the prefrontal cortex may also affect mood, motivation, and attention among people with depression.

When this happens, people with depression may experience executive dysfunction, meaning a person’s ability to manage their emotions, thoughts, and actions is disrupted. Executive dysfunction can also impact attention and concentration, says Jackson.

4. Depression’s Effects on the Prefrontal Cortex May Lead to Slower Processing Speed

Although the effects of depression on processing speed — “the speed at which you respond to questions, the speed at which you engage in conversation, the length of time it takes you to remember someone’s name,” Jackson says — are not often talked about, these effects can have profound daily implications on someone’s life.

In one study, researchers gave neuropsychological tests to 106 people with current major depression, 119 people with remitted major depression (meaning the symptoms have subsided), and 120 controls without major depression. They did this to study how depression affects processing speed, as well as learning and memory.

The results showed that people with current major depression had slower processing speed compared with both people with remitted major depression and controls.

Among those who have processing speed, attention, and concentration difficulties, the prefrontal cortex tends to show reductions in overall activity as well as reductions in synchronization with other regions, which means different parts of the brain might not be working together on complex tasks, says Nelson.

Are the Brain Health Effects of Depression Permanent?

Researchers don't know yet if the effects of chronic depression on the brain are permanent. But seeking professional treatment for depression — or sticking to your treatment, if you’ve already gotten help — can not only help you feel better emotionally, but it can help improve your brain health and cognitive well-being, too.

“The good news is that treatment can make a significant difference,” says Nelson. “Therapy, especially cognitive behavioral therapy (CBT), helps individuals develop strategies to address rumination and negative thinking patterns.”

If you suspect you have depression, know that seeking treatment early on can help avoid some of the effects on brain health before they happen, says Jackson. The potential signs and symptoms of depression include:

  • A sad, anxious, or empty mood that won’t go away
  • Feeling hopeless
  • Feeling irritable, frustrated, or restless
  • Losing interest in things you used to enjoy
  • Isolating yourself from friends and family
  • Having trouble sleeping or sleeping too much
  • Eating a lot less or a lot more than usual, leading to unintentional weight gain or loss
  • Having trouble remembering things, concentrating, or making decisions
  • Feeling aches, pains, digestive issues, or headaches that don’t have another medical explanation
  • Losing your desire for sex or intimacy
  • Using alcohol or drugs more frequently
  • Having suicidal thoughts or behaviors

The Takeaway

  • Depression is primarily a mood disorder, but over time, it can also affect brain health in general.
  • Brain changes as a result of depression can affect memory, processing speed, and concentration.
  • Researchers don’t yet know if changes in the brain caused by depression are permanent.
  • Seeking help for depression can improve your symptoms and potentially stave off problems with overall brain health.

Find Help Now

If you or a loved one is experiencing significant distress or having thoughts about suicide and need support, call or text 988 to reach the 988 Suicide & Crisis Lifeline, available 24/7. If you need immediate help, call 911.

Resources We Trust

EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. Recognizing the Lesser-Known Symptoms of Depression. National Alliance on Mental Illness. February 9, 2022.
  2. Dziurkowska E et al. Cortisol as a Biomarker of Mental Disorder Severity. Journal of Clinical Medicine. November 8, 2021.
  3. Han K et al. How Inflammation Affects the Brain in Depression: A Review of Functional and Structural MRI Studies. Journal of Clinical Neurology. September 17, 2021.
  4. Fan H et al. Relationship of prefrontal cortex activity with anhedonia and cognitive function in major depressive disorder: an fNIRS study. Frontiers in Psychiatry. September 18, 2024.
  5. Zaremba D et al. The effects of processing speed on memory impairment in patients with major depressive disorder. Progress in Neuro-Psychopharmacology and Biological Psychiatry. June 8, 2019.
  6. Depression. National Institute of Mental Health. 2024.
Meet Our Experts
See Our Editorial PolicyMeet Our Health Expert Network
Angela-Harper-bio

Angela D. Harper, MD

Medical Reviewer
Castle Connolly Top Doctor

Angela D. Harper, MD, is in private practice at Columbia Psychiatric Associates in South Carolina, where she provides evaluations, medication management, and psychotherapy for adults.  

A distinguished fellow of the American Psychiatric Association, Dr. Harper has worked as a psychiatrist throughout her career, serving a large number of patients in various settings, including a psychiatric hospital on the inpatient psychiatric and addiction units, a community mental health center, and a 350-bed nursing home and rehab facility. She has provided legal case consultation for a number of attorneys.

Harper graduated magna cum laude from Furman University with a bachelor's degree and cum laude from the University of South Carolina School of Medicine, where she also completed her residency in adult psychiatry. During residency, she won numerous awards, including the Laughlin Fellowship from the American College of Psychiatrists, the Ginsberg Fellowship from the American Association of Directors of Psychiatric Residency Training, and resident of the year and resident medical student teacher of the year. She was also the member-in-training trustee to the American Psychiatric Association board of trustees during her last two years of residency training.

Harper volunteered for a five-year term on her medical school's admission committee, has given numerous presentations, and has taught medical students and residents. She currently supervises a nurse practitioner. She is passionate about volunteering for the state medical board's medical disciplinary commission, on which she has served since 2015.

She and her husband are avid travelers and have been to over 55 countries and territories.

See full bio
Rena-Goldman-bio

Rena Goldman

Author
Rena Goldman is a journalist, editor, and content strategist with over a decade of media experience covering health, wellness, mental health, and small business. She has written on a variety of topics, including clinical conditions, lifestyle changes, fitness, new products, food, trends, and sleep.

Curious about what it takes to live your healthiest life in a modern society, Goldman is passionate about empowering readers with the information to make educated decisions about their health. She has spent years interviewing clinicians and working with them to ensure content is medically accurate. This experience has helped her build in-depth knowledge in the health and wellness space.

Goldman's work has been featured in numerous online health and lifestyle publications, including Everyday Health, Health.com, Healthline, Business Insider, Psych Central, and U.S. News & World Report.

She's based in Los Angeles, where she enjoys good vegan food, trying new workout trends, and hiking with her dachshund, Charlie.
See full bio
See Our Editorial PolicyMeet Our Health Expert Network