06/30/2026
Cognitive Dysfunction with Myasthenia Gravis
“Patients with MG frequently experience memory difficulties (60 %) and impaired performance on tests of response fluency, information processing, and verbal and visual learning—issues that show up even when mood is normal, the disease has been stable for years, or they’re on a steady low dose of immunosuppressive drugs. EEG abnormalities and abnormal evoked-potential responses appear in about 80 % of patients with MG. Some studies show real benefit from treatments like plasmapheresis, yet others report no change in cognitive function after the muscle symptoms improve.”
The quick stats:
• Prevalence: 30–60 % (please note that this is still heavily debated with some studies leaning even a little higher than the 60%. Outcomes depend on the tests used and the individuals tested)
• Severity: Usually mild to moderate as an academic assessment but patient self assessments often score between mild to severe with many influencing factors such as overall disease control, fatigue, stress etc…
• Domains most affected: Memory, attention, and executive function (by far the most consistent findings across studies) BUT it is not always limited to these findings as we will explore below.
Generalized fatigue, depression, anxiety, certain medications (especially high-dose steroids), natural aging, co-morbidities and sleep problems can be cofactors and influence some cognitive processes but it certainly does not explain the underlying mechanism or symptoms.
Some researchers believe that there is a central cholinergic dysfunction via anti-AChR antibodies may be interfering with acetylcholine receptors in the brain, though that idea is still being heavily debated as this does not explain the same phenomenon happening in MuSK and SNMG patients.
What the cognitive impairment actually feels like is largely subjective but the general consensus is that the deficits are fatiguable—your thinking/processing speed and accuracy drop faster the longer or the more you do the task, exactly like the muscle fatigue felt in our bodies.
You may also struggle with:
• Memory: trouble forming new memories, slower verbal learning, delayed recall, and forgetting things you just discussed in a conversation. Lists, frequent verbal or written reminders are often needed. Short term memory is usually what is most impacted in MG.
• Attention & processing speed: poor sustained attention, slower thinking, and that classic “brain fog.” Even simple tasks can feel overwhelming.
• Executive function: planning and organization slips, trouble switching between tasks, feeling overwhelmed with what to do next etc…
• Visuospatial / language: sometimes present as mild spatial issues (getting lost in familiar places or struggling with puzzles) and trouble with word recall.
For many years, this was considered to not be part of MG presentation. Many doctors (even MG specialists) were trained to dismiss this or chalk it up to poor sleep habits. But the truth is being affirmed as patients continue to speak up and research is slowly affirming this. While there is no direct treatment, looking at the whole picture can be very helpful. Do not hesitate to connect with your doctor and share this information with them and ask for a plan to move forward.
Author: Rebekah Dorr
MG Hope Foundation
Clinical references:
• Tucker DM, Roeltgen DP, Wann PD, Wertheimer RI. Memory dysfunction in myasthenia gravis: Evidence for central cholinergic effects. Neurology. 1988;38(3):1173–1177. (Classic Boston Naming Test and Wechsler Memory Scale study showing clear cholinergic effects.)
• Riker WF. Memory impairment in myasthenia gravis. Neurology. 1989;39(4):611–612.
• Davidov-Lustig M, Klinghoffer (Strich) V, Kaplan-Dinur A, Steiner I. Memory abnormalities in myasthenia gravis: Possible fatigue of central nervous system cholinergic circuits. Autoimmunity. 1992;14(1):85–86.
• Kazis A, Pappa A, Xafenias D. EEG findings in myasthenia gravis. Electromyogr Clin Neurophysiol. 1984;24(7):577–582.
• Paul RH, Cohen RA, Gilchrist JM, et al. Cognitive dysfunction in individuals with myasthenia gravis. J Neurol Sci. 2000;179(1-2):59–64. (Significant impairments in response fluency, information processing, verbal learning, and memory—moderate effect sizes compared with controls.)
• Paul RH, Cohen RA, Zawacki T, et al. What have we learned about cognition in myasthenia gravis? A review of methods and results. Neurosci Biobehav Rev. 2001;25(1):75–81.
• Marcassoli A, Trucco G, Mazzilli A, et al. Does myasthenia gravis impact cognitive functioning? A systematic review and meta-analysis. Neurol Sci. 2026;47(1):111. (Confirms selective problems in memory recall, processing speed, verbal fluency, and visuospatial skills.)
• Lupica A, et al. Frequency and Correlates of Mild Cognitive Impairment in Myasthenia Gravis. Brain Sci. 2023;13(2):170.
• Cognitive performance in patients with Myasthenia Gravis. Dement Neuropsychol. 2020;14(3): (worse memory and executive function, independent of disease duration or severity).
• Neuro-metabolic and brain functional alterations: Combined 1H-MRS and fMRI evidence of decline in global function, memory, and visuospatial domains (2024)
