Symptoms of clinical depression may include cognitive challenges, including difficulty solving problems, recalling information, and focusing on a task. Some people refer to the combination of these symptoms as brain fog.

Brain fog isn’t a formal diagnosis. The term may be used to indicate gradual or sudden challenges in your:

  • ability to think clearly or as usual
  • reaction time
  • memory and learning ability
  • executive functioning abilities like solving problems and making decisions

These challenges are common in people with clinical depression, especially when the condition goes untreated.

Brain fog symptoms in depression are clinically referred to as cognitive dysfunction.

Not everyone with depression will experience the same cognitive symptoms or with the same intensity.

In general, depression has various effects on the brain, and brain fog may manifest as:

  • Difficulty paying attention: You may not be able to complete a thought, follow a conversation, finish a task at work, or focus on a book, movie, or TV show.
  • Challenges with memory: You may have a hard time remembering what you were doing or wanted to do, may have to rely on writing things down to remember them, or find yourself losing things and missing important dates frequently.
  • Trouble with executive functioning: Your decision making may be challenged, which could lead you to persistently worry about possible outcomes. You may also find multitasking harder than usual.
  • Delayed reaction times: You complete tasks much more slowly than you used to, and time management and efficiency have become challenges.

Other possible symptoms of brain fog may involve:

  • difficulty with verbal communication (clarity, conciseness, and organization)
  • feeling distracted
  • not being able to follow instructions

Cognitive challenges aren’t the only symptom of depression, though. It’s also possible that brain fog has other causes, even if you live with depression.

To receive a diagnosis of depression, a healthcare professional will try to identify at least five out of nine formal symptoms. These symptoms must be present for most of the day, most days, for at least 2 consecutive weeks.

Formal symptoms of depression include:

  • low mood (sadness, hopelessness, emptiness)
  • reduced ability to enjoy everyday or special activities
  • low energy and motivation
  • changes in appetite (eating more or less than usual)
  • changes in sleep patterns (sleeping more or fewer hours than usual)
  • changes in movement patterns (moving slower or quicker than usual)
  • cognitive challenges (like brain fog)
  • thoughts of self-harm and death

If a doctor cannot determine depression is the cause of brain fog, they may want to explore other options, like thyroid dysfunction, COVID-19, anxiety, and brain injuries.

If brain fog is associated with depression, treatment for this condition may help brain fog as well. Untreated depression usually leads to more intense and persistent symptoms.

The first line of treatment for depression is psychotherapy. Options include:

CBT may be particularly helpful with symptoms of brain fog if you have depression.

For severe or persistent symptoms of depression, a healthcare professional may recommend antidepressants like sertraline (Zoloft), duloxetine (Cymbalta), or amitriptyline (Elavil).

Lifestyle modifications may also help with symptoms of depression, including brain fog. Depending on your needs and preferences, these may include:

Cognitive dysfunction or brain fog may persist even after depression treatment or in cases when symptoms don’t respond to traditional treatments. Some experts have theorized this may be due to a cognitive subtype of depression, which may require a different management approach than depression without brain fog symptoms.

Some research indicates that drugs like modafinil, vortioxetine, and donepezil may help with cognitive symptoms in some cases. More studies in humans are needed to determine effective treatments for persistent brain fog after depression.

If you continue experiencing symptoms of brain fog even after other symptoms of depression have decreased, consider talking with a healthcare professional. They may want to explore other diagnoses and treatment options.

Brain fog is a possible symptom of depression. It may manifest as difficulty remembering things, completing tasks, following instructions, making decisions, or focusing.

Treatment for depression may help relieve brain fog. Working with a healthcare professional can help you get the support you need.