The effects of trauma can linger. If you sometimes lack mental clarity and feel fatigued, you may be experiencing PTSD-related brain fog.

Post-traumatic stress disorder (PTSD) can arise after you experience a traumatic event. There are many symptoms, including nightmares, flashbacks, and panic attacks, which can occur spontaneously or when something reminds you of the trauma.

Because of its broad effects on the nervous system, PTSD can cause some less well-known symptoms, too, including dissociation, brain fog, and physical pain.

Experiencing trauma can affect your body and mind in various ways. If you’re living with the aftereffects of trauma, you might notice a slow, sluggish mental state known as brain fog getting in the way of your personal or work life.

What is brain fog?

As the name suggests, brain fog is when you’re unable to think clearly. You might experience:

  • spacing out or being unable to focus
  • feeling disconnected from your surroundings
  • difficulty with memory
  • trouble keeping up with conversations
  • a short attention span
  • losing your train of thought
  • feeling disoriented

Brain fog isn’t a condition on its own. Instead, it’s a symptom with a range of possible causes, one of which can be PTSD.

How can trauma cause brain fog?

PTSD and brain fog have something in common: inflammation. PTSD can lead to inflammation in the brain (neuroinflammation), which can contribute to brain fog.

Inflammation is a known contributing factor to physical health problems like cancer and heart disease — so it’s no surprise that PTSD-related neuroinflammation can lead to brain changes, as reported in a 2020 review.

The National Center for PTSD describes the relationship between inflammation and PTSD as bidirectional causal, which means the two cause or contribute to each other. They also identify a link between PTSD and autoimmune disorders, which research shows are also inflammation-driven.

Brain fog and nervous system changes

Your sympathetic nervous system responds to trauma with a fight, flight, freeze, or fawn response. This response protects you by preparing your body for action against a threat. During this response, your body releases the stress hormone cortisol.

At the right time and in the right amounts, cortisol can be extremely helpful. For example, it can give you the energy to save yourself by accessing fuel (glucose and fatty acids) in your liver.

In excessive amounts though, this stress response can lead to inflammation.

After trauma, your nervous system needs a chance to reset and return to the parasympathetic state known as “rest and digest.” This is because staying in fight-or-flight mode maintains a continuous state of stress that can wear out your body and cause unwanted health effects.

If you live with PTSD, you likely experience repeated stress responses in the form of intrusion symptoms. This means you may live with higher amounts of cortisol.

The elevated inflammation can occur anywhere in your body, including in your brain. This can lead to effects like:

Complex PTSD

Trauma-related nervous system effects are amplified in complex post-traumatic stress disorder (CPTSD). CPTSD arises from ongoing trauma, like repeated abuse. It can be current or from your childhood.

If you live with CPTSD, you are more likely to experience a continued stress response with even less recovery time.

The repeated or prolonged stress response from PTSD and CPTSD increases your circulating cortisol, which affects your immune system and causes inflammation.

According to the American Psychiatric Association (APA), PTSD symptoms fall into four categories:

  • Intrusion: unwanted thoughts, such as memories and distressing dreams.
  • Avoidance: refusing to talk about the trauma or avoiding people or situations that remind you of it.
  • Alterations in cognition and mood: distorted or harmful thoughts, like believing you’re to blame, or that no one is trustworthy.
  • Alterations in arousal and reactivity: mood shifts, potentially harmful behavior, hypervigilance, insomnia, and problems concentrating.

Brain fog is a type of alteration symptom that many people with a history of trauma experience.

You may be able to manage PTSD brain fog and reduce its effects. Self-care measures can calm your nervous system which may help you think more clearly.


Diet impacts brain function, and it helps to eat nutrient-dense food, like:

  • vegetables
  • fruits
  • whole grains
  • olive oil
  • fish
  • low fat dairy

The Mediterranean diet is considered beneficial for brain health. Replacing processed food with unprocessed options is another important step you can take.

If you’re feeling too overwhelmed to revamp your entire diet, making one change at a time can still help.


Research links sleep deprivation to neuroinflammation. So, if you’re living with PTSD and you can’t get enough sleep at night, this can intensify your brain fog.

Working on improving your sleep hygiene may help. This means building habits that help you sleep, like a wind-down routine, consistent sleep-wake times, and caffeine and screen cut-offs.


Exercise increases circulation through your body and brain, which helps delivers important nutrients to your brain. It can also help you sleep better.

The Centers for Disease Control and Prevention (CDC) recommends that adults get 150 minutes of moderate to intense exercise, plus two days of strength training, each week. You can distribute those minutes however you like, such as 30 minutes per day over five days.

If this feels like more than you can do right now, some exercise is better than none. It will still help to log more minutes even if you don’t reach 150 weekly.

Trauma-informed mindfulness

Mindfulness is a practice that can help calm your fight-or-flight response. It can help you relax and feel better.

For some people with trauma, mindfulness can trigger PTSD symptoms. If this happens to you, it may be helpful to try trauma-informed mindfulness with the help of a trained therapist.

Your nervous system responds to trauma with a protective stress response. For some people, that response is recurring or continuous, even after the traumatic event is over.

PTSD and CPTSD can make it hard for your nervous system to reset and rest. This results in persistently elevated inflammation, which can lead to brain fog.

You may be able to manage brain fog with some lifestyle interventions like dietary changes, consistent sleep, and regular exercise.

For more information about PTSD and how to manage its effects, you can visit Psych Central’s PTSD resource page.