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Electroencephalography Network Indices as Biomarkers of Upper Limb Impairment in Chronic Stroke
Published on: July 14, 2023
Alien hand syndrome in stroke - case report & neurophysiologic study -.
Yong Won Park1, Chang Hwan Kim, Myeong Ok Kim
1Department of Rehabilitation Medicine, Inha University College of Medicine, Incheon 400-711, Korea.
Annals of Rehabilitation Medicine
|September 15, 2012
Summary
Alien Hand Syndrome involves uncontrollable limb movements. Neurophysiological studies after anterior cerebral artery infarction revealed reduced motor evoked potential amplitude and impaired intracortical inhibition.
Area of Science:
- Neuroscience
- Neurology
Background:
- Alien Hand Syndrome (AHS) is characterized by involuntary, purposeful-seeming upper limb movements.
- Diagnosis requires a foreign limb sensation and complex, autonomous motor activity outside of known movement disorders.
- AHS can occur after cerebrovascular accidents affecting the corpus callosum, parietal, or frontal lobes.
Purpose of the Study:
- To investigate the neurophysiology of rare Alien Hand Syndrome cases following anterior cerebral artery (ACA) infarction.
- To explore the utility of transcranial magnetic stimulation (TMS) in understanding AHS.
Main Methods:
- Case study of two patients with AHS post-ACA infarct.
- Neurophysiological assessment including single-pulse motor evoked potential (MEP) and paired-pulse TMS for intracortical inhibition (ICI).
- Somatosensory evoked potential (SSEP) was also performed.
Main Results:
- One patient exhibited difficulty releasing objects, while the other experienced intermanual conflict.
- Both patients showed reduced MEP amplitude.
- Both patients demonstrated a lack of intracortical inhibition (ICI) via paired-pulse TMS.
Conclusions:
- Anterior cerebral artery infarction can lead to Alien Hand Syndrome with distinct clinical presentations.
- Neurophysiological findings suggest impaired corticospinal excitability and intracortical inhibition in AHS.
- TMS provides valuable insights into the neurophysiology of Alien Hand Syndrome.
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