6 Alarming Signs of Mental Fatigue (That You Can’t Ignore)

Mental fatigue is more than feeling lazy, bored, or dazed.

It can show up like a day when you feel totally drained to get out of your bed and face the world. When you wake up dreading going to work, it may be a sign that you’re mentally exhausted.

Something needs to change, so you don’t burn out.

Fatigue not only makes you mentally and emotionally exhausted, but it can also empty you out physically. It can make you reluctant to do even the most basic daily tasks. Even the thought of brushing your teeth or taking a bath overwhelms you.

While no one is immune to it, the good news is that mental exhaustion is both preventable and treatable.

What does it mean to be mentally fatigued?

Mental fatigue or mental exhaustion means a state of being drained of energy to perform or pursue anything that requires brain power (cognitive capacity). It is characterized by low mental energy, reduced willpower, and distracted focus. It is usually accompanied by physical tiredness, sleepiness, and lack of motivation.

Missed Signs of Mental Fatigue
Mental fatigue saps our motivation, making us simply want to lie on the couch doing nothing.

What are the stages of mental fatigue?

Most cases of mental fatigue start out languidly before becoming severe. Here is how it progresses:

1. Loss of focus

The first stage of mental exhaustion occurs when a person, who has been concentrating on something for an extended period of time, begins to feel tired and distracted.

They may struggle to concentrate and make the right decisions, but this may be easily fixed with some time off work, a nap, or a few days of vacation.

2. Mood changes

The second stage is when the person begins to feel depressed and irritable, which can lead to feelings of inadequacy, guilt, and self-doubt.

This is also when a person keeps feeling perpetually sluggish, confused, and weary, both in the mind and body.

3. Mental ill-health

The third stage happens when the person is utterly exhausted as a result of the constant mental effort required to perform at their best.

This is when they typically experience feelings of worthlessness and hopelessness that can lead to other mental health issues, including depression, anxiety, or even thoughts of self-harm.

5 Alarming Signs of Mental Fatigue That You Can’t Ignore

We usually assume that mental fatigue is purely a condition of the mind. That, however, is not the case. Mental exhaustion can also present as emotional, intellectual, and physical distress.

Here are the warning signs of mental fatigue:

1. Dull Headache.

Mentally fatigued people may feel unexpected muscle aches, body aches, and headaches.

One of the signs of mental fatigue is a dull headache, and it typically comes on slowly before other symptoms, like mood changes and forgetfulness, become noticeable.

A dull headache feels like a steady, low-grade pain that feels like a tight band around your head, especially your temples. It can be accompanied by odd dull aches anywhere in the body.

It mostly feels like a tension headache (one that you feel when stressed), not accompanied by vomiting, dizziness, blurry vision, or blackouts.

In any case, even if you feel it could be a migraine or sinus headache, consult your doctor.

2. Sense of Detachment.

A common symptom of mental fatigue is a sense of detachment, disinterest, or indifference. However, unlike the Stoics’ positive version of detachment, this detachment is demoralizing.

Mental exhaustion, sometimes known as ‘burnout,’ leads people to lose interest in activities they once enjoyed.

It could start gradually as you lose interest in your work, progressing until nothing thrills you any longer. As a result, you may begin to feel disconnected from reality, which can lead to frustration and despair.

3. Loss of Motivation.

Mental fatigue makes you look lazy and uncaring, but it is actually an extreme lack of energy that causes you to become helplessly unmotivated.

This lack of motivation may make others label you as an ambitionless, lackadaisical, or procrastinating person.

You lose your passion for things. Even the thought of doing the things you liked to do makes you so tired that you change the thought.

You may have loved to play chess or do rollerskating or do realistic sketching. But now, even imagining yourself going through those makes you shudder.

It is such a pitiful state that even the best motivational quotes don’t inspire you to get moving and be productive.

Worse, it may leave you hopeless and prevent you from seeking help. In time, it may lead to symptoms of depression.

4. Sleeplessness or Insomnia.

Insomnia is a major sign of mental fatigue. It involves difficulty falling asleep fast, remaining asleep, trouble going back to sleep after waking up, waking up multiple times during the night, and excessive sleep.

Fatigued people snore more, sleep badly, and sleep too much.

In fact, mental exhaustion can make you sleep for 10 hours or more, and still, you may feel tired and not rested enough upon waking up.

Insomnia is not just a lack of eight hours of sleep; it is more about the quality as well as the quantity of sleep you are getting each night.

This study found that disturbed sleep is an important predictor of mental fatigue, apparently stronger than already known factors such as workload, female gender, and lack of exercise.

What could be happening during the night is that your sleep is getting broken many times due to physical and mental pain, but the wakings are for so little time that you do not remember. A sleep scientist may record your sleep and reveal if it is the real reason behind your troubled sleep.

5. Feelings of Being Overwhelmed.

Feelings of being overwhelmed come when you feel you can no longer cope with a challenge. Mental fatigue makes you feel overwhelmed at things that require even the smallest of your efforts.

Feeling overwhelmed may cause you to respond to people asking you to do something with an irritated and subjugated attitude.

Since our brain has limited resources, it can make us feel overwhelmed when it is overworked and unrested. In mental fatigue, the brain preserves its resources to carry out the vital functions of survival and makes them unavailable for other things.

6. Mental Fatigue Anxiety (And Irritation).

Fatigue is a common sign of chronic anxiety. Fatigue is also often seen as a result of long-term anxiety. And anxiety in itself is an overwhelming condition.

So, if you feel mental fatigue, it is highly possible that you also have anxiety.

“Mental fatigue keeps the engine of anxiety humming all the time.”

Long-term anxiety can lead to major issues, such as panic attacks, inflammatory bowel syndrome (IBS), nausea, palpitations, and uneasiness.

In their quest to find out what aspects of stress are linked to fatigue, Hardy et al. identified work demands and role conflicts as two key causes.

Irritation is a state of feeling annoyed, impatient, or slightly angry.

In mental fatigue, irritation is the result of many factors, like unproductivity, apathy, lethargy, indecision, poor sleep, and fear of being judged.

By showing irritation, fatigued persons isolate themselves, so they can rest themselves as well as keep their distance from the demands and expectations of others.

So, a fatigued person tends to snap at others and withdraw from their social circles.

How to overcome mental fatigue?

Here are three simple ways to overcome mental fatigue:

1. Spot the early signs.

We already discussed the signs of mental fatigue above. Here are a few quick pointers:

  • Have you been feeling that getting out of your bed in the morning is a tough task?
  • Do you feel crushing tiredness coming over within hours of starting your work?
  • Do you find your focus and ability to take quick decisions going haywire?

If yes to any of them, then you could be suffering from mental fatigue.

2. Change your work-life habits.

If you can’t help but think about work while you’re on a break, you may be inching closer toward mental fatigue. Stop doing that.

Even if you work from home, leave work at work. When you meet people outside your work circle, try not to bring up business.

Let yourself truly relax when you are on a holiday.

3. Reduce exposure to the triggering event.

Sometimes, overexposure to any major event can lead to mental exhaustion, like “pandemic fatigue.”

It is mostly a milder form that can be easily treated by cutting back exposure to the situation, like limiting your access to news about the Covid-19 pandemic.

A related one is “quarantine fatigue.” If you’ve felt any of these, you’re likely to be going through quarantine fatigue: irritable, stressed, anxious, eating more or eating less, insomnia, unmotivated or unproductive, have racing thoughts, and generally tense.

4. Start a meditation routine.

Meditation improves mental function and teaches the mind to be still and calm.

Normally, our mind’s focus wanders for about half a second right after we focus. But after three months of meditation training, “attentional blink” was greatly reduced in the meditators (Slagter et al., 2007).

Researchers from Harvard, Yale, and MIT found evidence that meditation thickens the cerebral cortex, which is associated with improved cognitive abilities like memory.

Meditation enhances your ability to handle stress better (as shown in Mindfulness-Based Stress Reduction programs), and this can help you stop your exhaustion from worsening.

Here is a Beginner’s Guide To Start Mindfulness Meditation (with a free infographic and PDF).

Podcast 304: Sneaky signs of mental fatigue + a Neurocycle to heal mental fatigue
Dr. Caroline Leaf: How to manage mental fatigue and exhaustion


What does mental fatigue feel like?

Mental fatigue can make us feel exhausted, lethargic, sleepy, confused, unmotivated, and inactive. It dulls the feeling of positive emotions, and makes a person generally apathetic. It is more commonly felt by adults in high-stress jobs, although preteens and teenagers are increasingly reporting it.

What are the causes of mental fatigue?

Mental fatigue is often caused by long-term stress or disease, high work demands, lack of social support, lack of exercise, prolonged mental or physical exertion, and sleep deprivation.

In addition, researchers found that overweight and physical inactivity were predictors in men, whereas underweight was a factor in women (Bultmann & Kant, 2002).

Long periods of high mental concentration, unresolved emotional issues, unable to stop thinking about work during leisure time, and relationship conflicts may also trigger it.

Mental fatigue is a key feature of Burnout syndrome, Brain Fog, and Chronic Fatigue Syndrome (Holmes & Kaplan, 1998).

Is there a mental fatigue test?

For patients receiving mental fatigue treatment, the Mental Fatigue Scale (MFS) can be a helpful tool for getting a good picture of the current situation and tracking whether it is improving or worsening the condition.

Further Reading:

Final Words

If neglected for long, mental fatigue can lead to depression or worsen an underlying anxiety condition.

If identified early, mental fatigue is usually not very damaging and can be easily treated with professional help.

Get help from an expert. Consult your doctor or mental health professional.

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What Is Self-Kindness? How To Have More of It?

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Author Bio: Written and reviewed by Sandip Roy — medical doctor, psychology writer, and happiness researcher. Founder and Chief Editor of The Happiness Blog. Writes on mental health, happiness, mindfulness, positive psychology, and philosophy (especially Stoicism).

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When it comes to mental well-being, you don't have to do it alone. Therapists can help you work through your trauma triggers and emotional patterns. Reaching out to a professional to feel better is a positive choice.