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July 25, 2023

Decoding Brain Fog: Origins, Neurological Mechanisms, and Recovery  

by Brianna Rauchman

Brain fog can disrupt memory, focus, and overall well-being. Discover its diverse origins and how it affects neurological mechanisms. Plus, learn effective coping strategies to regain mental clarity and improve cognitive health.

Do You Suffer From Brain Fog?

Brain fog, a complex cognitive phenomenon, impacts countless lives, disrupting memory, focus, and overall well-being. Understanding the multifaceted nature of brain fog is vital, as it can stem from diverse origins, ranging from medical treatments like chemotherapy, neurological conditions such as multiple sclerosis, to the lingering effects of COVID-19 or stress-induced burnout. Keep reading to explore the causes of brain fog and effective coping strategies.  

Brain Fog Caused by Chemotherapy

What is “Chemo Brain”?

“Chemo Brain,” experienced by cancer patients undergoing chemotherapy, refers to cognitive difficulties that emerge during or after treatment. Studies have revealed that up to 75% of cancer patients may experience chemo brain to varying degrees. 

Female cancer patient sits in hospital chair while nurse gently touches her arm at Pacific Neuroscience Institute.


Chemo brain symptoms include memory lapses, difficulty concentrating, and a reduced ability to multitask. Patients might also struggle with word-finding and have trouble recalling recent events. 

Coping Strategies

Managing chemo brain involves cognitive exercises, such as puzzles and brain games, to stimulate neural pathways. Additionally, adopting a well-rounded lifestyle with regular physical activity, adequate sleep, and a balanced diet may mitigate its impact. 

Brain Fog Linked to Neurological Conditions

Overview of Neurological Conditions

Neurological conditions like multiple sclerosis (MS), Parkinson’s disease (PD), dementia, and stroke can lead to brain fog due to their impact on cognitive function. Each of these conditions affects the brain in distinct ways, contributing to cognitive impairments and causing brain fog as a prominent symptom. 

Multiple Sclerosis

Female doctor and male patient look at brain scan at Pacific Neuroscience Institute.

MS is classified as an autoimmune disease. Ordinarily, the immune system distinguishes the body as “self” and shields it against external agents like germs. Typically, the central nervous system (CNS), encompassing the brain, optic nerve, and spinal cord, restricts the entry of immune cells.

Barbara Giesser, MD, internationally recognized MS neurologist at Pacific Neuroscience Institute® (PNI®), explains that in patients with MS, “the immune system no longer recognizes parts of the CNS as ‘self.’” Consequentially, the immune system is able to infiltrate the CNS and target the nerves. This disruption affects cognitive abilities, causing brain fog along with other symptoms like fatigue and mobility issues. 

Parkinson’s Disease

In Parkinson’s disease, the gradual loss of dopamine-producing neurons in the brain leads to motor symptoms, such as tremors and stiffness, but can also result in cognitive changes, including memory problems and difficulties with attention and problem-solving. 

Natalie Diaz, MD, neurologist and Parkinson’s disease specialist at PNI, emphasizes that “the exact cause (of PD) remains unknown. Most people who develop PD are over 50 years old consequently making age the most significant risk.” However, there are a few genetic mutations that may predispose an individual to PD. Even so, risk is still influenced by environmental factors and lifestyle choices.


Dementia encompasses a range of neurological disorders, including Alzheimer’s disease, which progressively impairs cognitive function. According to Karen Miller, PhD, Senior Director of the Brain Wellness and Lifestyle Program℠ at PNI,“dementia is an overall decline in cognitive ability, usually impacting short-term memory (learning/recalling new information) and another cognitive ability (or more), such as decline in executive skills (organization, decision making) or language, or visual-spatial skills.” 

The accumulation of abnormal proteins in the brain, such as amyloid plaques and tau tangles, has been linked to Alzheimer’s disease and is thought to disrupt neuronal communication, leading to profound cognitive changes.


In the case of stroke, a sudden interruption of blood flow to the brain can result in a lack of oxygen and nutrients, leading to the death of brain cells in the affected area. Jason Tarpley, MD, PhD, Director of the Stroke and Neurovascular Center at PNI, explains that “a patient may appear normal for one second, and then suddenly undergo a neurological change that may present in various ways physically,” such as balance issues, facial droop, or blurred vision. 

Depending on the location and severity of the stroke, brain fog can manifest as a short-term or long-term effect, resulting in memory deficits, confusion, and difficulty understanding or expressing language. 

Importance of Early Detection for Neurological Conditions

Early diagnosis and intervention for neurological conditions play a crucial role in slowing disease progression and effectively managing cognitive symptoms. Engaging in lifestyle interventions such as regular physical and cognitive exercises can contribute to maintaining cognitive function and alleviating brain fog. 

If you suspect you or a loved one may be experiencing a neurological condition like MS, Parkinson’s, or dementia, it is essential to seek prompt medical attention from a healthcare provider. Developing a treatment plan early can significantly impact the course of the condition and improve overall well-being. Additionally, in the event of stroke symptoms, immediate contact with emergency services is critical to ensure swift and appropriate care

Brain Fog Following COVID-19

Understanding Post-COVID Brain Fog

Covid virus

The long-lasting effects of COVID-19, known as “Long COVID,” can include persistent brain fog even after the illness has resolved. Some individuals experience lingering cognitive difficulties, such as brain fog and mental fatigue, long after recovering from the initial infection. This condition affects people of all ages and can persist for several months. 

Possible Mechanisms

Post-COVID brain fog might be linked to inflammation affecting the brain or neurological impacts caused by the virus itself. The exact mechanisms are still under investigation. 

Rehabilitation and Recovery

Recovering from post-COVID brain fog may involve specialized cognitive and physical rehabilitation, alongside adopting a healthy lifestyle that includes proper nutrition and adequate rest. 

Brain Fog Resulting from Burnout and Stress

Identifying Burnout-Related Brain Fog

Woman at desk in a dimly lit room, illuminated by the soft glow of her computer screen. She appears overwhelmed and fatigued, as indicated by her closed eyes and a hand gently pressing against the bridge of her nose, suggesting she is experiencing burnout and stress.

Chronic stress and burnout have profound effects on mental clarity, contributing to brain fog. Burnout is a state of emotional, mental, and physical exhaustion resulting from prolonged stress and overwhelming work demands. The constant release of stress hormones can negatively impact brain function. 

Cognitive symptoms related to burnout can include forgetfulness, difficulty concentrating, and a general feeling of mental cloudiness, making it challenging to focus on tasks. 

Restoring Mental Clarity

Effective stress management techniques, such as mindfulness practices, regular exercise, and seeking support from friends, family, or mental health professionals, are essential for restoring cognitive clarity and combating brain fog. 

Personalized Support for Brain Wellness and Cognitive Health

Ryan Glatt, MS, CPT and a client in the FitBrain gym at Pacific Neuroscience Institute

Brain fog presents a complex array of causes and challenges. From medical treatments to neurological conditions, COVID-19, and stress-induced burnout, the origins of brain fog are diverse and often interconnected. Recognizing the importance of early detection and intervention for specific conditions is crucial. Seeking professional help and adopting lifestyle modifications, cognitive exercises, and stress management techniques offer promising avenues to mitigate the impact of brain fog on daily life.  

Fortunately, the Brain Wellness and Lifestyle Program at Pacific Neuroscience Institute offers personalized guidance to optimize your cognitive health. Our program incorporates curated courses that blend science-based interventions with holistic care, offering comprehensive support for your cognitive health.  Backed by reputable research, our methods have been specifically designed to empower individuals to take control of their cognitive well-being. Courses are available in-person or virtual, as well as group or individual sessions.

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About the Author

Brianna Rauchman

Brianna Rauchman, BA, is the Communications Coordinator for the Lifestyle Program, where she helps develop outreach strategies to connect with an expanding audience. Her responsibilities include providing launch support, developing content, assisting with collateral design, and planning social media strategies.

Last updated: July 28th, 2023