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Central positional nystagmus: Characteristics and model-based explanations.

Jeong-Yoon Choi1, Ji-Soo Kim1

  • 1Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea; Department of Neurology, Seoul National University College of Medicine, Seoul, South Korea.

Progress in Brain Research
|July 22, 2019
PubMed
Summary

Central positional nystagmus (CPN) arises from disruptions in the vestibular system. Lesions can cause transient (paroxysmal) or persistent CPN, impacting rotational velocity and gravity estimation.

Keywords:
Central positional nystagmusNodulusNystagmusUvulaVelocity-storageVertigo

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Area of Science:

  • Neuroscience
  • Ophthalmology
  • Vestibular System Research

Background:

  • The central vestibular system interprets ambiguous peripheral vestibular input to determine head orientation and motion.
  • Lesions affecting this system can lead to central positional nystagmus (CPN).

Purpose of the Study:

  • To classify and differentiate the characteristics of paroxysmal and persistent forms of central positional nystagmus.
  • To explore the neural mechanisms and potential lesion locations underlying CPN.

Main Methods:

  • Clinical observation and classification of nystagmus based on patient positioning.
  • Correlation of nystagmus characteristics with suspected central vestibular pathway involvement, particularly the velocity-storage circuit and cerebellar structures.

Main Results:

  • Paroxysmal CPN exhibits features indicative of semicircular canal involvement, with latency, duration, and direction varying by provoking position.
  • Persistent CPN typically manifests as downbeat or horizontal (apogeotropic/geotropic) nystagmus depending on head position.
  • Both forms may stem from disruptions in the velocity-storage circuit, with specific cerebellar regions implicated in paroxysmal (nodulus, uvula) and persistent CPN (gravity estimation).

Conclusions:

  • CPN presents in distinct paroxysmal and persistent forms, each with characteristic nystagmus patterns.
  • Erroneous neural processing within the velocity-storage circuit is a likely cause of CPN.
  • Lesion overlap in the cerebellum can explain the frequent co-occurrence of both paroxysmal and persistent CPN in patients.