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Mental deterioration in Lafora's disease
A Cukiert1, M M Vilela, H B Scapolan
1Department of Neurology, São Paulo University, School of Medicine, Brasil.
Arquivos De Neuro-Psiquiatria
|June 1, 1990
Summary
Lafora disease, a progressive myoclonic epilepsy, causes early dementia even before social life is disturbed. Neuropsychological testing reveals significant cognitive decline, particularly in non-dominant hemisphere functions.
Area of Science:
- Neuroscience
- Neurology
- Epilepsy Research
Background:
- Lafora disease is a rare, fatal neurodegenerative disorder.
- It is classified as a progressive myoclonic epilepsy.
- Dementia is a hallmark symptom, but its early progression is understudied.
Observation:
- Two early-diagnosed Lafora disease cases underwent comprehensive neuropsychological testing.
- Testing occurred before patients reported mental deterioration.
- Subsequent tests documented rapidly progressive dementia.
Findings:
- Severe impairment of right parietal lobe functions was consistently observed.
- Cognitive deficits included constructional praxis, memory, and abstract processing.
- Language and intellectual functions were relatively preserved.
- Dominant hemisphere cognitive functions showed less impairment than non-dominant ones.
Implications:
- Mental deterioration is an early, potentially presymptomatic, manifestation of Lafora disease.
- The disease causes asymmetrical cognitive deficits, suggesting complex neuropathology.
- Further research is needed to understand the mechanisms behind this asymmetry.
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