ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

301–320 of 397 studies

E2 ModerateCohortPEM not requiredCase-Control

Attention and short-term memory in chronic fatigue syndrome patients: an event-related potential analysis.

Scheffers, M K, Johnson, R, Grafman, J et al.·Neurology·1992

This study compared brain activity and reaction times between 13 people with ME/CFS and 13 healthy volunteers using brain scans while they performed attention and memory tasks. The ME/CFS patients showed much slower and more variable reaction times, but their memory and thinking abilities appeared normal. The researchers found that the brain's basic attention and memory processes were working similarly in both groups, suggesting the slowness came from problems with how the brain signals muscles to respond.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

Illness perception and symptom components in chronic fatigue syndrome.

Ray, C, Weir, W R, Cullen, S et al.·Journal of psychosomatic research·1992

This study asked 208 people with ME/CFS about their symptoms and how they experience their illness. Researchers found that ME/CFS involves four main types of problems: emotional distress, fatigue, physical symptoms, and difficulty thinking clearly. Emotional distress did not directly determine how sick people felt overall, but negative emotions did make the other symptoms worse.

Cognitive Impairment

E3 PreliminaryCohortPEM requiredCase-Control

Significant aggravation of pre-existing myalgic encephalomyelitis/chronic fatigue syndrome following proton beam therapy for sphenoid wing meningioma: case report.

Fischer, Christian, Seidlitz, Annekatrin, Krause, Mechthild·Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et al]·2026

This is a single case report of a 46-year-old woman with ME/CFS whose condition severely worsened after receiving proton beam radiation therapy for a brain tumor. Over months following treatment, she went from being ambulatory to completely bedridden, with worsening fatigue, pain, dizziness, and cognitive problems. The report suggests that radiation may have triggered this deterioration, but it remains unclear whether this outcome would occur in other ME/CFS patients undergoing similar treatment.

Pain and SensitizationSevere MEEnergy MetabolismCognitive Impairment

E3 PreliminaryMechanismPEM unclearCross-Sectional

Reduced Adenosine Triphosphate-to-Phosphocreatine Ratios in Neuropsychiatric Post-COVID Condition: Evidence From 31P Magnetic Resonance Spectroscopy.

Weber-Fahr, Wolfgang, Dommke, Sandra, Sack, Markus et al.·Biological psychiatry·2026

This study looked at how the brain produces and uses energy in people with long COVID and cognitive problems. Using a special brain imaging scan, researchers found that people with long COVID have lower energy levels in a part of their brain called the cingulate cortex, and this energy shortage is linked to thinking and memory problems. The findings suggest that problems with how brain cells produce energy may be a key reason why some people experience cognitive difficulties after COVID-19.

Cognitive Impairment

E3 PreliminaryMechanismPEM unclearCross-Sectional

Autonomic phenotyping, brain blood flow control, and cognitive-motor-integration in Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome: A pilot study.

Badhwar, Smriti, Pereira, Tania J, Kerr, Kathleen et al.·Autonomic neuroscience : basic & clinical·2025

This study compared how the nervous systems of ME/CFS patients, Long COVID patients, and healthy people respond to physical stress tests like breathing different air mixtures and tilting upright. The researchers found that ME/CFS and Long COVID patients had different patterns of problems: ME/CFS patients showed difficulty controlling blood flow to the brain during one test, which was linked to coordination problems, while Long COVID patients had lower oxygen levels when upright and their nervous systems didn't adapt as well.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryReviewPEM not requiredReview-Narrative

Retracted: Chronic Epipharyngitis Treated with Epipharyngeal Abrasion Therapy: Symptoms, Diagnosis, Pathogenesis, and Treatment Outcomes.

Harabuchi, Yasuaki, Kumai, Takumi, Nishi, Kensuke et al.·JMA journal·2025

This article discusses chronic epipharyngitis—long-term inflammation in the upper throat—and describes a treatment called epipharyngeal abrasion therapy (EAT) that aims to reduce this inflammation. The authors note that this throat inflammation may cause various symptoms including fatigue, brain fog, dizziness, and cough, and they review evidence that EAT might help some patients, including those with long COVID. However, this paper has been retracted and should not be relied upon for clinical decisions.

Cognitive Impairment

E3 PreliminaryCohortPEM unclearCase-Control

Improvement in Upper Limb and Systemic Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Symptoms After Surgical Treatment of Neurogenic Thoracic Outlet Syndrome.

Christoforou, Maritsa E, Lum, Ying Wei, Sroge, Sally C et al.·Cureus·2025

This case study describes a 19-year-old woman with ME/CFS who also had a condition called thoracic outlet syndrome (TOS), where nerves in the upper chest become compressed. After surgery to relieve this compression on both sides of her body, she experienced not only relief from arm numbness and tingling, but also surprising improvements in migraines, brain fog, dizziness, and vision problems. This suggests that some ME/CFS patients might benefit from being evaluated for TOS, as treating it could potentially help with multiple symptoms.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryMechanismPEM requiredPreprintPreprint

Dissecting the genetic complexity of myalgic encephalomyelitis/chronic fatigue syndrome via deep learning-powered genome analysis.

Zhang, Sai, Jahanbani, Fereshteh, Chander, Varuna et al.·medRxiv : the preprint server for health sciences·2025

Researchers used advanced artificial intelligence to analyze the genes of ME/CFS patients and discovered 115 genes that may contribute to the disease. They found that people with ME/CFS have lower levels of these risk genes active in their immune cells and nervous system. This genetic analysis could eventually help doctors diagnose ME/CFS more accurately and identify new treatment targets.

BiomarkersImmune SystemCognitive ImpairmentPost-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

[Modern approaches to diagnosis and treatment of postinfectious asthenic syndrome in children].

Nemkova, S A·Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova·2025

This review article discusses postinfectious asthenic syndrome—a condition causing severe tiredness and weakness that develops after infections like colds, flu, and COVID-19 in children and teenagers. The authors examine how this condition develops, its symptoms, and how a medication called Mexidol may help reduce fatigue and improve thinking, mood, and nervous system problems that often accompany it.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryGuidelinePEM unclearGuideline

Improving quality in adult long covid services: Findings from the LOCOMOTION quality improvement collaborative.

Darbyshire, Julie, Greenhalgh, Trisha, Bakerly, Nawar D et al.·Clinical medicine (London, England)·2024

This study looked at how ten long COVID clinics across the UK could improve their care for patients by sharing what they were learning with each other. From 2021 to 2023, clinic staff and patients met regularly to discuss the best ways to help people with long COVID, focusing on problems like breathing difficulties, heart rate issues, tiredness, and brain fog. The team created practical guides to help doctors provide better, more consistent care.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryReviewPEM not requiredReview-Narrative

The interplay between Sars-Cov-2 infection related cardiovascular diseases and depression. Common mechanisms, shared symptoms.

Gonjilashvili, Ana, Tatishvili, Sophio·American heart journal plus : cardiology research and practice·2024

This review examines how COVID-19 can affect both the heart and mental health, and why these problems often occur together. The authors explain that inflammation, unhealthy lifestyle changes, and communication between organs may all play a role. They note that long COVID shares many symptoms with heart and brain problems—like fatigue, brain fog, dizziness, chest pain, and depression—which is why patients need care from multiple medical specialists.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryMechanismPEM unclearMechanistic

Six-Week Supplementation with Creatine in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Magnetic Resonance Spectroscopy Feasibility Study at 3 Tesla.

Godlewska, Beata R, Sylvester, Amy L, Emir, Uzay E et al.·Nutrients·2024

Researchers gave 11 people with ME/CFS a creatine supplement (a natural substance that helps cells produce energy) for 6 weeks. Brain scans showed the supplement increased creatine levels in key brain regions, and participants reported feeling less fatigued, had faster reaction times on thinking tests, and showed stronger hand grip strength. The supplement was well tolerated with no side effects reported.

Cognitive Impairment

E3 PreliminaryMechanismPEM not requiredMechanistic

Effect of electroacupuncture on expression of protein phosphorylation in hippocampus tissues of rats with chronic fatigue syndrome.

Yang, Yan, Sun, Zhong-Ren, Li, Chao-Ran et al.·Zhen ci yan jiu = Acupuncture research·2024

Researchers tested whether acupuncture with electrical stimulation could help rats with an artificially induced fatigue-like condition. After 28 days of treatment, the acupuncture-treated rats showed improvements in their overall condition, anxiety levels, and memory compared to untreated rats. The researchers found changes in brain proteins that might explain how the treatment helped.

Cognitive Impairment

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

The Cognitive and Behavioural Responses to Symptoms Questionnaire (CBRQ): Development, reliability and validity across several long-term conditions.

Picariello, Federica, Chilcot, Joseph, Chalder, Trudie et al.·British journal of health psychology·2023

This study tested a questionnaire called the CBRQ that measures how people think about and respond to their symptoms in ways that might make them worse or keep them the same. The researchers checked whether this questionnaire works well across different long-term illnesses, including chronic fatigue syndrome (ME/CFS), and found that it reliably measures seven different thought and behaviour patterns. They also created and tested a shorter version of the questionnaire that works just as well.

Cognitive Impairment

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Asthenia, mental fatigue and cognitive dysfunction].

Titova, N V, Bezdolny, Yu N, Katunina, E A·Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova·2023

This article discusses asthenia, which is a condition characterized by extreme tiredness that affects daily functioning and productivity. The authors explain that it's important to distinguish between simple chronic tiredness and chronic fatigue syndrome (CFS), and that fatigue can affect both the body and the mind. The article reviews how the brain may be involved in causing fatigue and cognitive problems, and suggests that a combination treatment using specific medications may help patients with fatigue and thinking difficulties.

Cognitive Impairment

E3 PreliminaryMechanismPEM unclearCross-Sectional

Altered brain connectivity in Long Covid during cognitive exertion: a pilot study.

Barnden, Leighton, Thapaliya, Kiran, Eaton-Fitch, Natalie et al.·Frontiers in neuroscience·2023

Researchers used advanced brain imaging to compare how the brains of Long Covid patients and healthy people respond during a challenging thinking task. They found that Long Covid patients showed different patterns of communication between brain regions, particularly in areas that control alertness, heart rate, and sleep. These brain connection differences were linked to how disabled patients felt and their autonomic nervous system symptoms.

Cognitive Impairment

E3 PreliminaryCohortPEM not requiredCross-Sectional

What is brain fog?

McWhirter, Laura, Smyth, Heather, Hoeritzauer, Ingrid et al.·Journal of neurology, neurosurgery, and psychiatry·2023

This study looked at how people describe 'brain fog' by analyzing online discussions on Reddit. Researchers found that brain fog involves many different experiences—trouble remembering things, difficulty concentrating, feeling disconnected from reality, thinking slowly, trouble communicating, and fatigue. Brain fog appeared in discussions about many conditions, with long COVID being the most commonly mentioned cause.

Cognitive Impairment

E3 PreliminaryReviewPEM not requiredReview-Narrative

Exploring the arcuate fasciculus from a clinical perspective.

Shao, Zhi Ding, Gong, Yu Juan, Ren, Jing et al.·Frontiers in neuroscience·2023

This review examines a bundle of nerve fibers in the brain called the arcuate fasciculus, which helps connect language centers. Researchers found that several conditions—including ME/CFS, stroke, brain tumors, and others—can damage these nerve fibers in measurable ways. New brain imaging techniques can now visualize and measure this damage, which may help doctors understand what goes wrong and develop better treatments.

Cognitive Impairment

E3 PreliminaryReviewPEM not requiredSystematic-Review

Understanding mental fatigue and its detection: a comparative analysis of assessments and tools.

Kunasegaran, Kaveena, Ismail, Ahamed Miflah Hussain, Ramasamy, Shamala et al.·PeerJ·2023

Mental fatigue is a common problem that makes it harder to concentrate, process information, and make decisions. Currently, doctors mainly ask patients to describe their fatigue using questionnaires, which can be unreliable because people's answers are subjective. This review compared different methods of detecting mental fatigue—including questionnaires, heart rate measurements, stress hormones, brain scans, and eye movement tests—to find the most objective and accurate tool.

Cognitive Impairment

E3 PreliminaryCommentaryPEM not required

The Potential Role of Hypothalamic Phospholipid Liposomes in the Supportive Therapy of Some Manifestations of Post-COVID-19 Condition: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Brain Fog.

Menichetti, Francesco·Journal of clinical medicine·2023

This article discusses how a treatment called hypothalamic phospholipid liposomes might help with ME/CFS and brain fog symptoms in people with Long COVID. These liposomes are small fatty particles that are already available as a supportive treatment for brain and hormone-related problems. The authors suggest this treatment could be helpful based on how it works and their early clinical experiences, though more rigorous testing is still needed.

Cognitive Impairment

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Attention and short-term memory in chronic fatigue syndrome patients: an event-related potential analysis.

Illness perception and symptom components in chronic fatigue syndrome.

Significant aggravation of pre-existing myalgic encephalomyelitis/chronic fatigue syndrome following proton beam therapy for sphenoid wing meningioma: case report.

Reduced Adenosine Triphosphate-to-Phosphocreatine Ratios in Neuropsychiatric Post-COVID Condition: Evidence From 31P Magnetic Resonance Spectroscopy.

Autonomic phenotyping, brain blood flow control, and cognitive-motor-integration in Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome: A pilot study.

Retracted: Chronic Epipharyngitis Treated with Epipharyngeal Abrasion Therapy: Symptoms, Diagnosis, Pathogenesis, and Treatment Outcomes.

Improvement in Upper Limb and Systemic Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Symptoms After Surgical Treatment of Neurogenic Thoracic Outlet Syndrome.

Dissecting the genetic complexity of myalgic encephalomyelitis/chronic fatigue syndrome via deep learning-powered genome analysis.

[Modern approaches to diagnosis and treatment of postinfectious asthenic syndrome in children].

Improving quality in adult long covid services: Findings from the LOCOMOTION quality improvement collaborative.

The interplay between Sars-Cov-2 infection related cardiovascular diseases and depression. Common mechanisms, shared symptoms.

Six-Week Supplementation with Creatine in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Magnetic Resonance Spectroscopy Feasibility Study at 3 Tesla.

Effect of electroacupuncture on expression of protein phosphorylation in hippocampus tissues of rats with chronic fatigue syndrome.

The Cognitive and Behavioural Responses to Symptoms Questionnaire (CBRQ): Development, reliability and validity across several long-term conditions.

[Asthenia, mental fatigue and cognitive dysfunction].

Altered brain connectivity in Long Covid during cognitive exertion: a pilot study.

What is brain fog?

Exploring the arcuate fasciculus from a clinical perspective.

Understanding mental fatigue and its detection: a comparative analysis of assessments and tools.

The Potential Role of Hypothalamic Phospholipid Liposomes in the Supportive Therapy of Some Manifestations of Post-COVID-19 Condition: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Brain Fog.

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