Glossary of Terms in Otolaryngology

Ewald’s Laws

  • Ewald’s Laws are 3 laws that describe behaviours of the vestibular system. They were initially described by the German physiologist J.R. Ewald in 1892.1
  • Ewald’s 3 Laws are:2
    1. Ewald’s First Law: Stimulation of a semicircular canal results in nystagmus in the same plane as the stimulated canal.
    2. Ewald’s Second Law: In the lateral canal, ampullopetal flow (towards the ampulla) causes more stimulation than ampullofugal flow.
    3. Ewald’s Third Law: In the anterior and posterior canals, ampullofugal flow (away from the ampulla) produces a stronger response than ampullpetal flow.

Anatomy of the Inner Ear and Semicircular Canals

  1. Ewald, Julius Richard. “Physiologische Untersuchungen uber das Endorgan des Nervus octavus.” Bergman (1892). ↩

  2. Fife, Terry D. “Overview of anatomy and physiology of the vestibular system.” Handbook of Clinical Neurophysiology 9 (2010): 5-17. ↩

Last updated October 08, 2022
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