Hearing

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Block A5 - Nervous System and Sense Organs


Physiology
Office:5th floor, Radiopoetro
Lab:5th floor, Radiopoetro
Work-plan:None.
Pre-test:5 questions, multiple-choice.
Post-test:10 questions, multiple-choice.
Lab Report:One report per tutorial group:
  • Introduction
  • Reagents/Equipment
  • Procedure
  • Result
  • Discussion
  • Interpretation
  • References


  • Weber Test:
    • Tuning fork is placed in the center of the the forehead or head and the examiner is asked which ear is the sound louder in.
    • Sensorineural hearing loss: lateralization to (louder in) the normal ear.
    • Conductive hearing loss: lateralization to the abnormal ear.
  • Rinne Test:
    • Tuning fork placed on mastoid process and then when the sound disappears, held in front of ear. If there's sound heard, positive Rinne.
    • Positive test when air conduction (AC) is better than bone conduction (BC).
    • Sensorineural deafness: positive Rinne.
    • Conductive deafness: negative Rinne (BC>AC).
  • Schwabach Test:
    • Tuning fork is placed on patient's mastoid. Patient lets examiner know when they cannot hear the sound anymore. The examiner immediately places the tuning fork on their own mastoid. This can be repeated vice-versa.
    • Sensorineural hearing loss: If examiner hears the sound longer than the patient. Aka "diminished Schwabach".
    • Conductive hearing loss: If patient hears the sound longer than the examiner. Aka "prolonged Schwabach".

In other words...

  • Test results indicating CHL:
    • Prolonged Schwabach
    • Negative Rinne
    • Negative Bing
    • Weber lateralizes to bad ear
  • Test results indicating SNHL:
    • Diminished Schwabach
    • Positive Rinne
    • Positive Bing
    • Weber lateralizes to good ear


  1. The major cation in endolymph is potassium, and there is virtually no sodium.
  2. An influx of potassium ions depolarizes the cell and causes the release of a neurotransmitter that can initiate nerve impulses in the sensory neurons that synapse on the base of the hair cell.