Brain Fog, Foggy Head Anxiety Symptoms

What causes brain fog, foggy-headed?

Relating to anxiety, there are a number of reasons why brain fog and foggy head symptoms occur. Here are five:

1. An active stress response

Behaving apprehensively activates the stress response, a part of the body’s survival mechanism, which secretes powerful stress hormones into the bloodstream that prepare the body for emergency action.[1][2]

In addition to the many changes the stress response brings about, it also causes a change in brain functioning so that we are better equipped to deal with a threat.

The stress response causes many body-wide changes, including changing how the brain function. For instance, the stress response:

A. Increases activity in the areas of the brain responsible for fear detection and reaction (amygdala and others) and suppresses areas of the brain responsible for executive function (cortex)[2]

This change in brain function heightens awareness and reaction to danger so that we can react to it quickly rather than remaining in it while we figure things out.

While this is beneficial when in real danger, it can make rationalizing seem slow and difficult, which can be experienced as “brain fog” or “foggy brain.”

B. Increases electrical activity in parts of the brain[3]

Increased electrical activity causes an increase in thought generation. This change can cause our attention to be more easily sidetracked, which can cause split attention and focus making it seem like our thoughts are “foggy” and not “clear-headed.”

C. Suppresses the hippocampus – the learning and memory area of the brain[4][5]

Hippocampal suppression can make it more difficult for the brain to store and retrieve information.

Any of the above changes can cause a “brain fog” feeling.

2. Hyperstimulation

When stress responses occur infrequently, the body can recover relatively quickly from the physiological, psychological, and emotional changes the stress response brings about. When stress responses occur too frequently, however, such as from overly apprehensive behavior, the body has a more difficult time recovering, which can cause it to remain in a state of semi stress response readiness. We call this state “stress-response hyperstimulation” since stress hormones are stimulants (also often referred to as "hyperarousal" or HPA axis dysregulation).[6][7][8] Hyperstimulation can cause the changes of an active stress response even though a stress response hasn’t been activated.

As we mentioned, the stress response suppresses the rationalization areas of the brain (the cortex) and increases activity in the fear centers of the brain (the amygdala, others). This combination reduces the ability to logically rationalize and process information while at the same time increases the awareness of danger, fear, apprehension, gloom and doom.

As hyperstimulation increases, so can the persistence of these brain function changes. Chronic brain function changes can cause chronic “brain fog” and “memory problems.”

3. Fatigue

Hyperstimulation taxes the body’s energy resources harder and faster than normal. Chronically taxed energy resources can cause the body to become tired more quickly.[9]  Fatigue can make processing, storing, and retrieving information difficult.

As well, studies have shown that the brain tires more quickly than the rest of the body.[10] An exhausted brain loses its ability to think, remember, and reason sooner than the body fatigues. This is why you can feel physically fine yet experience “brain fog” and mental fatigue.

4. Cognitive load fatigues the brain

Just as hyperstimulation can fatigue the body, psychological and emotional stress (cognitive load) can fatigue brain function.[11] A tired brain can cause issues with thinking, which can be experienced as “foggy” brain.

5. Sleep deprivation

Hyperstimulation often causes problems with sleep. Chronic sleep problems can impact energy levels and brain function, which can cause “foggy brain.”[12]

These are just seven of the many ways stress and chronic stress (hyperstimulation) can adversely affect concentration and short-term memory.

6. Dehydration

Without sufficient fluids, the volume of blood decreases, which can cause blood pressure to drop and the amount of blood and oxygen that reaches the brain to decrease. This change can cause “brain fog,” difficulty concentrating, and confusion symptoms.[13]

7. Medication

Many medications, including common psychotropic medications (anti-anxiety, antidepressants, mood stabilizers, etc.) can cause a variety of side effects when starting them, taking them regularly, missing dosages, switching to another medication, in combination with other medications and over-the-counter medications, and when discontinuing them.[14]

“Brain fog,” difficulty concentrating, confusion, and memory problems are common side effects.

8. Nutritional deficiency

Stress taxes the body’s nutritional resources. A nutritional deficiency can also cause “brain fog,” confusion, and memory problems.

9. Hyperventilation and Hypoventilation[15]

When you are stressed, anxious, or think you are in danger, stress hormones are released into the bloodstream. Stress hormones cause the body to change its breathing patterns from slow, deeper breaths to either rapid, deeper breaths (hyperventilation) or to rapid, shallow breaths (Tachypnea). When your breathing changes to either of these patterns, carbon dioxide (CO2) levels in the bloodstream decrease. Low levels of CO2 can cause difficulty thinking and concentration problems, which can be experienced as “brain fog.”

Moreover, some people hold their breath or under breathe when they are stressed or anxious, which can cause hypoventilation (not enough oxygen). Not enough oxygen increases CO2 in the blood, which can also cause difficulty thinking and concentration problems, which can be experienced as “brain fog.”

Both hyperventilation and hypoventilation can cause “brain fog” symptoms.

10. Chronic pain

Pain stresses the body.[16][17] As such, pain, especially chronic pain, can stress the body sufficiently to cause mild degrees of hyperstimulation and aggravate existing hyperstimulation.

If you have anxiety disorder or hyperstimulation and its symptoms, having to deal with pain, especially chronic pain, can aggravate anxiety, hyperstimulation and their symptoms, including “brain fog.”

11. Inward focused

Another consideration is that many anxiety disorder sufferers become internally focused (ruminate about their health, how they feel, the implications of anxiety disorder and how that might affect their future, concerns about recovery, questions about recovery, what others will think because of their struggle with anxiety, how their struggle might affect loved ones, and so on).

Being internally focused can easily distract us away from external focus by all of the “what if” thinking. It’s common to become so obsessed with trying to figure out anxiety disorder that everything else takes a back seat, including our attention and focus on the external parts of our lives.

Internally focused and “what if” thinking can become so habituated and automatic that many sufferers aren’t even aware that they are doing it.

When short-term memory and concentration problems occur, many anxious people become concerned and think that they may be losing their minds, think that they may be on the verge of a complete mental breakdown, or think that their brain fog is an indication of a serious mental or biological illness. These anxieties can add even more stress to an already hyperstimulated body, making symptoms worse.