What happens when we’re too connected to our phones?
It begins subtly—maybe you lose your train of thought mid-sentence, forget why you walked into a room, or reread the same paragraph three times without absorbing a word. You’re not tired, not distracted, and yet, your mind feels like it’s trying to swim through quicksand.
For millions, this isn’t a one-off moment. It’s a daily struggle known as brain fog. Once casually mentioned in support groups and chronic illness forums, the term has now earned a spotlight in scientific discourse, especially in the aftermath of COVID-19.
But what is brain fog, really? Where does it come from, and why does it strike so many, so differently? From immune system misfires to the mysteries of the microbiome, click through this gallery to uncover the science of brain fog.
Despite its prevalence, brain fog remains a poorly defined medical phenomenon, often lacking a clear diagnostic criterion. Scientists have only recently started piecing together what causes it.
A significant number of individuals who recover from COVID-19 experience lingering cognitive symptoms referred to as brain fog. These can include poor concentration, memory lapses, and difficulty with daily tasks, all of which severely impact their quality of life post-infection.
Although COVID-19 brought the term “brain fog” into public awareness, it has long been recognized in people suffering from chronic conditions such as fibromyalgia, lupus, chronic fatigue syndrome, and even as a side effect of medications or chemotherapy.
Patients battling chronic conditions frequently describe brain fog as one of the most debilitating symptoms. Common complaints include an inability to focus, mental confusion, forgetfulness, and a general slowing down of thought processes that interfere with everyday living.
Regardless of the underlying condition, brain fog manifests similarly across different illnesses. Neuropsychologists have noted that this includes clouded thinking, poor memory, and sluggish cognition.
The term “brain fog” lacks a strict clinical definition and isn’t considered a standalone diagnosis. Instead, it serves as a catch-all for cognitive issues stemming from various medical conditions, which can complicate both diagnosis and treatment.
Experts believe brain fog reflects issues in critical cognitive functions. It indicates that the brain is not operating optimally, even if standard medical tests don’t show measurable abnormalities.
Patients often feel invalidated when test results fail to confirm their cognitive struggles. Many undergo extensive evaluations, only to be told their brain function appears normal. This leads to frustration and feelings of being misunderstood or dismissed by clinicians.
There is a tendency among some healthcare providers to attribute brain fog purely to psychological causes. This bias particularly affects people with long COVID or chronic illnesses, and contributes to a delay in treatment.
Researchers now believe that brain fog likely stems from a variety of causes, differing between individuals and conditions. This growing consensus may open doors to more nuanced and targeted approaches to understanding and addressing this complex symptom.
One prevailing hypothesis is that brain fog results from neuroinflammation. Conditions like long COVID can trigger an overactive immune response, which persists even after the initial illness subsides, and disrupts brain function through ongoing inflammation.
Research suggests that COVID-19 may activate immune cells in the brain and disrupt neuronal growth. This leads to cognitive decline and structural brain changes, including reduced gray and white matter, all of which contribute to long-term brain fog.
In some cases, COVID-19 prompts the production of autoantibodies, which mistakenly attack healthy brain cells. This autoimmune response may further aggravate neuroinflammation and cause persistent cognitive deficits in individuals recovering from the virus.
Scientists believe remnants of the virus may even linger in the brain, keeping the immune system in a state of high alert. This continuous immune activity can result in prolonged inflammation and cognitive issues among long COVID sufferers.
A recent study found that many long COVID patients with brain fog had leaky blood-brain barriers. This barrier normally protects the brain from harmful substances, but when compromised, it can let in toxins and worsen cognitive dysfunction.
When the blood-brain barrier becomes permeable, it allows harmful elements to enter the brain, which can ignite inflammation and interfere with metabolism. This further contributes to the onset and persistence of brain fog symptoms.
Changes in hormone levels, such as during menopause, have been associated with reductions in brain region sizes and cognitive performance. These hormonal shifts might be a significant but underexplored factor contributing to brain fog symptoms.
In people with hypothyroidism, insufficient thyroid hormones are linked to reduced brain volume. This is especially true in the hippocampus, which may impair memory and thinking.
Brain fog symptoms are also common after traumatic brain injuries. These cases often involve low levels of growth hormone, which can affect brain function and mimic the same cognitive difficulties seen in long COVID and other conditions.
Interestingly, the gut microbiome might also influence brain fog. Some studies have linked digestive conditions to cognitive haziness, potentially through microbial imbalances that promote systemic inflammation and affect brain health.
Researchers believe the gut-brain connection might play a role in long COVID-related brain fog as well. Disruptions in gut bacteria could contribute to inflammation and brain changes, although this hypothesis still requires further investigation.
Experts recommend addressing lifestyle factors like exercise, diet, and sleep first. These foundational habits can improve overall brain health and may reduce mild cases of brain fog.
Persistent or severe brain fog should prompt a visit to a doctor. Clinicians can rule out reversible causes (such as sleep apnea or nutritional deficiencies) and look for signs of inflammation or neurodegenerative diseases.
Cognitive rehabilitation therapy can help patients with significant cognitive impairments. This type of therapy targets the brain’s weakest areas, functioning like mental exercise to rebuild cognitive strength and enhance overall mental performance.
Some patients (especially those with chemo-related brain fog) report improvements with ADHD medications. These treatments may help improve focus and attention, though more research is needed to determine their broader effectiveness.
Antihistamines and drugs like famotidine (which possess anti-inflammatory properties) are being investigated for their potential to relieve brain fog. Early results are promising, particularly for reducing inflammation associated with long COVID.
Medical practitioners are also looking into intravenous immunoglobulin (IVIG) as a means of treatment. It involves the infusion of donated antibodies, which is typically done for autoimmune diseases. The goal is to suppress harmful immune activity and protect brain cells from damage.
Researchers are also looking into checkpoint inhibitors (used in cancer immunotherapy) as a treatment for long COVID. These drugs may help recalibrate the immune response and reduce the neuroinflammation believed to cause brain fog.
Despite its vague terminology, brain fog is a real and deeply disruptive symptom for many people. Instead of dismissing it, researchers and doctors are now viewing it as a valuable window into broader neurological dysfunctions that they could potentially treat in the future.
Sources: (National Geographic) (News-Medical)
See also: Understanding the concept of brain rot
Brain fog: the new long COVID symptom
The emerging science on cognitive dysfunction
HEALTH Coronavirus
It begins subtly—maybe you lose your train of thought mid-sentence, forget why you walked into a room, or reread the same paragraph three times without absorbing a word. You’re not tired, not distracted, and yet, your mind feels like it’s trying to swim through quicksand.
For millions, this isn’t a one-off moment. It’s a daily struggle known as brain fog. Once casually mentioned in support groups and chronic illness forums, the term has now earned a spotlight in scientific discourse, especially in the aftermath of COVID-19.
But what is brain fog, really? Where does it come from, and why does it strike so many, so differently? From immune system misfires to the mysteries of the microbiome, click through this gallery to uncover the science of brain fog.