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Cognition

Brain FogEvidence & Dosage

Multifactorial: sleep, blood sugar, inflammation, thyroid, long COVID.

Studies last updated

Evidence at a glance

Total studies
1,000
With abstract
46
Meta / Systematic / RCT
66
Highly cited
21
Publication years
2002–2026

Brain Fog in the context of Cognition

This topic is part of our "Cognition" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.

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Top studies on Brain Fog

Ranked by influential-citation count and publication year.

  1. Meta-analysis on the interrelationship between sarcopenia and mild cognitive impairment, Alzheimer's disease and other forms of dementia.

    J Cachexia Sarcopenia Muscle2024n=58meta160 influential citations

    Sarcopenia has been associated with adverse health outcomes, including cognitive dysfunction. However, its specific interrelationship with neurocognitive disorders such as mild cognitive impairment (MCI), Alzheimer's disease (AD) or other…

  2. Outcomes associated with postoperative cognitive dysfunction: a systematic review and meta-analysis.

    Age Ageing2024n=20Meta-Analysis105 influential citations

    <h4>Background</h4>Postoperative cognitive dysfunction (POCD) manifests as a subtle decline in cognition, potentially leading to unfavourable postoperative outcomes. We explored the impact of POCD on physical function, length of hospital…

    Finding: Postoperative cognitive dysfunction was not associated with functional decline after surgery.

  3. Neuroimaging Insights into the Public Health Burden of Neuropsychiatric Disorders: A Systematic Review of Electroencephalography-Based Cognitive Biomarkers.

    Medicina (Kaunas)2025Systematic Review66 influential citations

    <i>Background and Objectives</i>: Neuropsychiatric disorders, including schizophrenia, bipolar disorder, and major depression, constitute a leading global public health challenge due to their high prevalence, chronicity, and profound…

  4. Positive Impacts of a Four-Week Neuro-Meditation Program on Cognitive Function in Post-Acute Sequelae of COVID-19 Patients: A Randomized Controlled Trial.

    Int J Environ Res Public Health2023n=34RCT65 influential citations

    Study objective: Long COVID patients can experience high levels of impairment in their cognitive function and mental health. Using a parallel randomized control trial, we evaluated the effectiveness of a neuro-meditation program to reduce…

  5. The Prevalence of Cognitive Impairment in Relapsing-Remitting Multiple Sclerosis: A Systematic Review and Meta-analysis.

    Neuropsychol Rev2025n=5,859Meta-Analysis62 influential citations

    It is increasingly recognized that cognitive symptoms are a common sequelae of relapsing-remitting multiple sclerosis and are associated with adverse functional consequences. However, estimates of cognitive impairment (CIm) prevalence vary…

  6. Cognitive reserve and cognition in mood disorders: A systematic review and meta-analysis.

    Psychiatry Res2024Meta-Analysis59 influential citations

    Cognitive functioning heterogeneity is a well-recognized phenomenon in individuals diagnosed with mood disorders. Cognitive Reserve (CR) has been linked to multiple positive outcomes, including cognitive performance in these patients. This…

  7. Cholinergic system in schizophrenia: A systematic review and meta-analysis.

    Mol Psychiatry2025n=295Meta-Analysis51 influential citations

    <h4>Background/objectives</h4>Studies have shown widespread alterations in different components of the cholinergic system in schizophrenia, but to date the evidence has not been systematically reviewed and summarized. Here, we…

  8. Intervention modalities for brain fog caused by long-COVID: systematic review of the literature.

    Neurol Sci2024n=17systematic48 influential citations

    Individuals suffering from long-COVID can present with "brain fog", which is characterized by a range of cognitive impairments, such as confusion, short-term memory loss, and difficulty concentrating. To date, several potential…

  9. Association of Vestibular Disorders and Cognitive Function: A Systematic Review.

    Laryngoscope2024Systematic Review46 influential citations

    <h4>Objectives</h4>The purpose of this study is to consolidate and condense the available evidence about the potential association between vestibular diseases and cognitive impairment.<h4>Data sources and methods</h4>A systematic search…

  10. Cognition in cerebellar disorders: What's in the profile? A systematic review and meta-analysis.

    J Neurol2025n=3,140Meta-Analysis43 influential citations

    <h4>Objective</h4>This systematic review and meta-analysis aim to examine the profile and extent of cognitive deficits in patients with cerebellar disorders, and to provide a complete overview of the cognitive domains that might be…

Frequently asked

What dosage was studied?
• Postoperative cognitive dysfunction (POCD) assessment (Not reported)
Are there safety considerations for Brain Fog?
• Postoperative delirium may confound POCD-outcome associations. • Not reported • Theta burst stimulation caused transient dizziness and headache. • Scalp pain occurred in 4/23 patients after TMS.

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