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Updated: Jul 2, 2026
06:35
In Vivo Electrophysiological Measurement of Compound Muscle Action Potential from the Forelimbs in Mouse Models of Motor Neuron Degeneration
Published on: June 15, 2018
Primary progressive myoclonus of aging.
Maria Alvarez1, John N Caviness
1Department of Neurology, Wilford Hall Medical Center, San Antonio, Texas, USA.
Summary
A new syndrome, primary progressive myoclonus of aging (PPMA), affects older adults. This condition is characterized by action myoclonus without dementia or other neurodegenerative features.
Area of Science:
- Neurology
- Geriatrics
Background:
- Myoclonus in older adults often indicates underlying neurological disorders.
- A newly identified syndrome, primary progressive myoclonus of aging (PPMA), presents without typical associated neurological features.
Purpose of the Study:
- To characterize the clinical and electrophysiological features of primary progressive myoclonus of aging (PPMA).
- To differentiate PPMA from other neurodegenerative conditions in the elderly.
Main Methods:
- Retrospective review of medical records and electrophysiology data for 7 patients meeting PPMA criteria.
- Criteria included asymmetric action myoclonus, age ≥65, cortical myoclonus physiology, absence of dementia, and no secondary causes.
Main Results:
- Seven patients met PPMA criteria, presenting between ages 70-87.
- Electrophysiology confirmed cortical myoclonus; no patients had dementia or remarkable brain imaging.
- The mean duration of symptoms was 2.9 years.
Conclusions:
- Primary progressive myoclonus of aging (PPMA) is a distinct syndrome in older individuals.
- Differentiating PPMA is crucial to avoid misdiagnosis with dementias or other neurodegenerative diseases.
- Levetiracetam showed potential therapeutic benefit in some cases.
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