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Published on: March 11, 2020
Abnormal intracortical facilitation in early-stage Huntington's disease
Summary
Early Huntington's disease (HD) patients show reduced paired-pulse intracortical facilitation (ICF), indicating motor cortex changes. This neurophysiological evidence supports altered NMDA receptor function in HD pathogenesis.
Area of Science:
- Neuroscience
- Neurology
- Neurophysiology
Background:
- Neuronal degeneration in Huntington's disease (HD) is advanced by the time clinical symptoms appear.
- Early detection of neurophysiological changes is crucial for understanding HD pathogenesis.
Purpose of the Study:
- To detect neurophysiological changes using transcranial magnetic stimulation (TMS) in early-stage HD.
- To investigate motor cortex excitability in relation to early HD pathogenesis.
Main Methods:
- Examined motor cortex excitability in 12 early-stage HD patients and 15 controls using TMS.
- Assessed central motor conduction time, motor thresholds, cortical silent period, short-interval intracortical inhibition (SICI), and paired-pulse intracortical facilitation (ICF).
Main Results:
- Early-stage HD patients exhibited a statistically significant reduction in paired-pulse intracortical facilitation (ICF).
- No significant differences were observed in other TMS measures between HD patients and controls.
Conclusions:
- Findings provide neurophysiological evidence of motor function changes in early HD.
- Reduced ICF suggests altered intracortical glutamatergic excitatory circuits, supporting a role for NMDA receptor dysfunction in HD.
- These insights may aid in earlier HD diagnosis and intervention.
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