One of the most frustrating experiences for any student going to school or working adult is experiencing “brain fog.” When brain fog hits, it’s almost as if our previously efficient brain has filled up with clouds or “fog” that prevents us from thinking clearly. Brain fog is typically characterized as an inability to focus, poor memory functioning, and difficulty learning new things.
Although you may not experience all of the classic brain fog symptoms, most people know when they have foggy mental functioning. Experiencing brain fog is extremely unpleasant and can be depressing in itself because it interferes with our ability to perform on the job and/or maintain a sufficient level of productivity. When you have brain fog, it may seem as if you are thinking in slow-motion, are easily distracted, and daydream a lot.
Brain Fog Causes: A List Of Possibilities
There are many things that can lead a person to experience brain fog; below is a list of possibilities. Realize that it is possible for a person to experience multiple contributing factors to their brain fog (e.g. lack of sleep and medication). It may be of significant benefit to find out what’s causing your particular brain fog so that you can manage it and improve your clarity.
ADHD: People with ADHD tend to show differences in brain activity compared to those who are able to focus. It is thought that brain fog as a result of ADHD can be a result of low levels of dopamine, low arousal, and excessive slow brain wave rhythms. Since there are different types of ADHD, not everyone with this condition will experience brain fog. Those who have the inattentive subtype usually have more difficulty with foggy thinking.
Alcohol: Drinking alcohol is known to lower arousal and depresses the CNS. If you have brain fog, drinking alcohol is likely going to magnify the problem. If you are a frequent drinker and experience brain fog, it could be due to your alcohol consumption. In order to regain your mental clarity, it would help to give up alcohol for awhile and your focus should improve. Those who have ever had a wicked hangover can attest to the brain fog that they experience.
Anxiety: Not all types of anxiety will result in brain fog. Many actually stimulate us so much that there is zero fog in the brain, just hyperarousal. Anxiety can interfere with our ability to perform basic cognitive functions. It may affect memory retrieval, communication processing, and may lead us to experience brain fog. Additionally many anxiolytic medications that are used to treat anxiety tend to increase brain fog as a result of suppressing activity in the CNS.
Brain injuries / brain damage: Any sort of brain injury or damage could result in impaired cognitive abilities. For example, if someone got into a bad accident and experienced a TBI (traumatic brain injury), they may experience significant brain fog as a result of the trauma. Other brain injuries can result from a stroke, or temporary loss of blood flow to the brain – causing damage. In some cases the brain can recover after these injuries, but in other cases the fog only improves with psychostimulant medications.
Brain tumors: Any brain tumors or other lesions throughout the brain can influence brain activity. These will usually show up on an MRI scan. Depending on where the tumor is located, it can have different effects on your cognition. The position and size of the tumor can affect the degree to which you experience brain fog and other mental processing.
Brain waves: If you hook an EEG up to your brain, you will be able to determine the electrical activity or the speed of your brain waves. The electrical or brain waves occurring throughout your brain could be a cause of slow thinking or slow mental processing. An expert will easily be able to assess whether your EEG appears “healthy” or “abnormal” based on the brain waves observed in particular regions. Usually when a person has significant slow-wave activity overpowering fast-wave activity, it is a sign of brain fog.
Chronic Fatigue Syndrome: This condition is characterized by feeling fatigued for at least 6 months. If there’s any condition that brain fog is likely to be potent and overwhelming, it’s this one. Those with chronic fatigue syndrome typically lack the energy to complete tasks and stay productive. The problem is that this fatigue is not only physical, but it’s mental – affecting a person’s entire cognition.
Depression: People who are clinically depressed tend to report brain fog more often than those who aren’t. If you have depression, cloudy thinking and impaired cognition are often common symptoms. Those who are depressed may report slow task performance and/or speaking so slowly that others seem to notice. Psychomotor activity tends to be slower in those who are depressed than among individuals who are happy.
Diabetes: During cases of hypoglycemia, or low blood sugar, brain fog can become a prominent symptom. A person who has low blood sugar may appear dazed, talk nonsensically, and/or exhibit a noticeable communication impairment. The brain relies on glucose to provide it with energy. When glucose levels drop to an abnormally low level, the brain isn’t receiving fuel to properly function and brain fog occurs.
Diet: If you aren’t eating enough food, you are essentially depriving your brain of the energy that it needs to function properly. The foods that you eat give your body energy and help you think clearly. By eating enough food and a healthy diet, you are giving your brain the best possible chance to think clearly and stay focused. Nutritional deficiencies can lead a person to experience brain fog and impair mental health.
Excessive exercise: There are many psychological benefits of exercise – one of which can be improving concentration and healthy brain activity. However, if a person overexerts themselves physically by spending too much time at the gym, they are exhausting themselves mentally too. If you noticed that you are feeling mentally foggy after working out too long, it’s probably related to your workout. Take a break or consider being a little bit less hardcore so that you don’t have as much brain fog.
Fibromyalgia: Although this condition is characterized by pain at various sites throughout the body, fatigue and foggy thinking are also very common. Various changes in arousal and neurotransmitters are thought to contribute to fibromyalgia. Individuals with this condition tend to experience significant difficulties organizing their thoughts and memories.
Hormonal imbalances: A variety of conditions can lead to hormone imbalances. Medical conditions, medications, drugs, and menopause can all result in hormonal fluctuation. There is evidence that suggests hormone changes can impair our thinking; thus leading to brain fog.
Hypothyroidism: This condition is characterized by the thyroid not producing adequate amounts of thyroid-stimulating-hormone. When the body is deficient of thyroid hormone, it leads to impairments in mental processing and learning. Once properly treated, the brain fog should gradually subside.
Illicit drugs: Using illicit drugs, especially those that act as depressants (e.g. heroin) can lead to foggy mental processing. Even stimulants such as cocaine may initially help brain fog, over the long-term it can create even more impairments in cognition. Additionally coming down or “crashing” from an illicit stimulant can result in excessive brain fog until the brain repairs itself.
Low arousal: Individuals who have naturally low levels of arousal may be more prone to brain fog. Low levels of arousal are usually related to depression and ADHD. They tend to be characterized by slow brain waves, less stimulating neurotransmitters (i.e. less dopamine) and changes in brain activation. In other words, the stimulation throughout an individual’s nervous system can be abnormally low during waking hours, thus leading to deficiencies in beta waves, dopamine, and prefrontal cortex activation.
Lyme Disease: This can be very tricky to deal with because most people that have severe cases of Lyme have no clue that they have it. They may notice a severe decline in ability to think critically and may become easily confused. This condition can cause people to become emotionally irritable and result in difficulty controlling impulses. Some individuals have claimed that they lose their entire memory functioning as a result of swelling in the brain. If this isn’t detected early enough, the symptoms of brain fog may end up becoming permanent.
Menopause: During menopause, it is common for hormone levels to change. The changing hormones can lead a person to experience increased tiredness and in some cases, brain fog. If you experience foggy thinking during menopause, it’s likely due to changes in hormone levels. In most cases the fog will subside as soon as the hormones return to homeostasis.
Lupus: This is essentially a diagnosis for autoimmune diseases in which the immune system attacks the body, and compromises its health. A person with lupus may experience a variety of physical symptoms, as well as unwanted mental symptoms. Many people report experiencing low energy and a significant amount of brain fog.
Multiple sclerosis: This is a disease in which nerve cells responsible for protecting the brain and spinal cord become damaged. The damage affects the entire nervous system and usually impairs physical and mental functioning. This disease can lead to permanent neurological problems such as chronic fatigue, poor cognition, and severe brain fog – especially over the long-term.
Neurodegenerative disorders: A variety of neurodegenerative disorders are known to cause brain fog. In cases of these specific disorders, usually a person will lose brain functioning and exhibit structural changes in their brain. This affects all forms of cognition and makes it difficult to retrieve memories, process information, and learn. Most of these diseases are believed to be influenced by genetic factors and can kill brain cells and/or permanently impair cognition.
- Alzheimer’s: This is the most common type of dementia and is usually prevalent among those over age 65, but can appear earlier. Those with Alzheimer’s tend to experience reductions in cognition and memory processing.
- Dementia: This is a symptom of many diseases that affects an individual’s ability to think logically and with reason. In general people with dementia experience a significant loss of cognitive abilities.
- Huntington’s: This is another disorder characterized by uncontrollable movements and impaired cognition. It tends to affect middle-aged adults and will inevitably result in brain fog, among many other mental symptoms.
- Parkinson’s: This is a degenerative disease that affects the CNS. People often experience movement disorders and significant mental impairment as a result of an inability to produce the neurotransmitter dopamine.
Neurotransmitters: An individual with neurotransmitter imbalances can exhibit symptoms of brain fog. Usually when there is an imbalance, a person will have a very difficult time thinking clearly. This is especially common when a person withdraws from an antidepressant and they experience a newly-created chemical imbalance. (Read: Antidepressants cause a chemical imbalance). Brain fog can also be created when a person has abnormally low levels of dopamine production – as in the case of ADHD.
Oversleeping: Getting too much sleep can be detrimental to one’s physical and mental health. Sleeping too much or “hypersomnia” is associated with depression, fatigue, and obesity. If you frequently get too much sleep, this could cloud your thinking. Sleep is known to be restorative, but when a person sleeps in excess, it is thought to slow cognitive functioning.
Overworking: Even though over-working may result in a person becoming increasingly stressed, this stress can lead to brain fog. In other cases, too much work may just cause someone to become fatigued or tired. You may notice that when you get too caught up in your work and don’t take enough time to recover that you feel mentally foggy. The solution is to simply cut back on work hours and take more time to manage your health.
PTSD: In some cases of PTSD, a person eventually experiences so much stress that their focus improves. In the event that a person becomes hypervigilant and the anxiety overpowers their depression, the person may not experience brain fog. However, in other cases of those with PTSD, they may frequently daydream and experience significant depression and brain fog. This is characterized by theta waves on an EEG, making the person feel emotionally traumatized and cognitively impaired.
Schizophrenia: Many individuals with schizophrenia experience reduced cognition and extremely low energy. This can be a result of taking antipsychotic medications and/or a result of the disease itself. Individuals with schizophrenia tend to experience negative symptoms, which increase depression and brain fog to a significant extent. The cognitive symptoms of the disease may also make it very difficult to think clearly.
Side effects: Sometimes certain drugs can make people feel tired, drowsy, and a significant degree of brain fog. This is very common for individuals taking antipsychotics and in some cases brain fog is reported as an antidepressant side effect. Even illicit drugs that tend to lower our arousal may also have a detrimental effect on cognition; making it more difficult to think clearly.
Sleep deprivation: Getting little sleep or depriving yourself of adequate sleep can lead to significant brain fog. Adequate sleep is considered healing, a good protector against stress, and tends to improve mental functioning. Those who skip sleeping or don’t get enough of it will usually notice some sort of brain fog. Lack of sleep results in EEG changes, hormone changes, and results in concentration difficulties.
Stress: When stress levels become high, brain functioning can change significantly. Some types of stress such as PTSD can cause us to become less focused and easily distracted by our trauma. Although some stress may actually improve our cognition and brain fog, other types may serve as a detriment to our mental functioning.
Withdrawal: People often report feeling brain fog during withdrawal from drugs. Whether you are withdrawing from a psychotropic drug or an illicit drug – brain fog is often reported. The specific chemical causes of brain fog can differ based on the drug. For example, during opioid withdrawal lack of endorphins could be causing the fog, while during stimulant withdrawal, lack of dopamine could be contributing to the fog. In general, when a person stops using a drug, their brain needs time before it will readjust to normative functioning.
Note: There are likely more causes of brain fog than what’s listed above. If you are aware of another specific cause of brain fog, feel free to share it in the comments section below.
My personal experiences with brain fog
There have been many times throughout my life when I’ve experienced brain fog. In fact, as I’m writing this article, I have an extremely bad case of it. It’s so bad that during my outline for this article, all of my main points were jumbled. I couldn’t think of the words that I wanted to say, and the writing process is taking significantly longer than it probably should.
- Anxiety: In my case, I have always had generalized anxiety and some degree of social anxiety. Although many people equate anxiety with increased stimulation and less brain “fog” – this is not always the case. Although anxiety can help increase focus for some, in my case it actually decreases it. My thinking becomes sporadic and in many cases everything inside my head seems foggy.
- Brain waves: I have noted that brain fog tends to be influenced somewhat by brain waves. Although slower brain waves don’t always lead to “foggy” thinking, in general a lack of sufficient beta waves on an EEG can be a factor. I have noticed that when I am aroused with high beta waves, I experience significantly less overall brain fog.
- Depression: When I become depressed, I lack the capability to think clearly and express my thoughts. It becomes difficult to verbalize certain words and I have a tough time thinking of the words I’m trying to say when communicating. Even when I’m typing, I know the general concepts that I’m going to type, but the details become a total blur. It’s almost as if I wish my head could spit out the ideas because when it comes time for me to verbalize and/or write the concepts I’m trying to convey, my brain becomes foggy.
- Diet: I notice that when I eat a poorer diet or don’t eat enough food, my thinking becomes cloudy and less focused. When I make sure I’m eating a breakfast, lunch, and diner and feel “full” after each meal, I usually notice less brain fog. During times when I am not as stringent about eating breakfast, I may notice brain fog throughout the entire morning of my work day.
- Introversion: When I’m in social situations, it’s almost as if my mind goes completely blank. Instead of being quick-witted, I’m actually extremely slow witted. I do my best to think of conversational topics and/or prime myself for conversation, but it’s almost as if I’m trying to start up an old car engine just for spurts to get me through a conversation. Not all introverts have the same “foggy” introversion that I do, in fact many usually never experience brain fog.
- Low arousal: When I have a low level of arousal, I notice that my brain fog tends to increase. When I get riled up and physiologically aroused to a high degree, my focus and thinking improves. My thoughts become more organized. As I noted in my article about adrenaline levels and depression – low levels of adrenaline don’t really improve brain fog. But when they become high enough to act as a naturally-produced stimulant, they relieve depression and clear up all brain fog.
- Side effects: Over the course of years taking psychotropic medications, I’ve noticed that certain ones resulted in my thinking becoming foggy. I remember when I took Cymbalta I experienced some of the foggiest thinking in my entire life. Other medications that turned my brain to a fog cloud included Effexor, Lexapro, and Celexa. The worst culprit for brain fog though was Xanax – which makes total sense; it reduces CNS activity. I also experienced it during a brief stint taking an antipsychotic.
- Withdrawal: I experienced very extreme brain fog when I quit Paxil cold turkey, as well as during many other antidepressant withdrawals. It is common to experience brain fog during withdrawal from any drug. Over time, I reverted back to a homeostatic level of “clarity.” Unfortunately for me, I was born with somewhat “foggy” thinking and always had a difficult time processing things in school. I’d see the teachers lips moving, writing information, and hear the words, but nothing really sank in – making it tougher to learn.
Determining the cause of brain fog
For many individuals it can be beneficial to know what is causing their brain fog. In the event that there is a treatment for a particular cause that is causing your clouded thinking, you can pursue it. Often times it may be difficult to pinpoint a specific cause for the foggy thinking, but with the help of a doctor, psychologist, or psychiatrist, you can likely figure out some contributing factors.
Let’s say you experience brain fog as a result of having ADHD. After you’ve figured out that you are naturally inattentive and have a difficult time thinking clearly, you may benefit significantly from daily meditation, exercise, and/or a psychostimulant. On the same token, someone who is experiencing brain fog from sleep deprivation may need to just improve their sleep and their cognition and mental clarity will also improve.
Understand that brain fog is usually different based on the individual circumstances. For one person it may be a result of drug withdrawal, for another it may be due to a condition such as chronic fatigue syndrome. If you have personally dealt with brain fog and/or have identified what caused it, feel free to share your experience in the comments section below.
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