II. Physiology: Hearing

  1. See Vestibular Function
  2. Outer Ear
    1. Sound waves enter the external auditory canal and reach the Tympanic Membrane (Ear Drum)
    2. Tympanic Membrane vibrates in response to sound waves
  3. Middle Ear
    1. Ossicles vibrate as a sequence of gears, amplifying the vibration signal from the Tympanic Membrane
      1. Malleus (hammer)
      2. Incus (anvil)
      3. Stapes (stirrup)
    2. Stapes attaches to the oval window, passing the vibratory signal into the Cochlea of the inner ear
    3. Middle ear communications
      1. Eustachian tube
        1. Functions as a Pressure Equalization Tube to allow for Tympanic Membrane vibration
        2. Exits to the posterior nasopharynx
      2. Mastoid antrum
        1. Communicates with the mastoid air cells
  4. Inner Ear: Cochlea
    1. Inner ear contains two sensory organs
      1. Cochlea (snail shell shape)
        1. Converts sound waves to electrical sensory signals transmitted centrally by the Cochlear Nerve
      2. Semicircular canals
        1. Three semicircular canals sense head position and transmit centrally via the Vestibular Nerve
        2. See Vestibular Anatomy
    2. Sound waves are transmitted to a fluid filled chamber (scala vestibuli) via the oval window
      1. Perilymph fluid within the scala vestibuli carries sound waves to the Cochlear duct
      2. Perilymph fluid surrounds the Cochlear duct
        1. Returns to the base of the Cochlea via the scala tympani
        2. Scala tympani ends at the round window (inferior to the oval window) at the middle ear
    3. Signal vibrates the tectorial membrane and Organ of Corti hair cells
      1. Different sound frequencies vibrate different hair cells along the course of the Organ of Corti
    4. Organ of Corti hair cells generate impulses in response to vibration
      1. Signal is transmitted centrally via the Cochlear Nerve
  5. Inner: Ear: Perilymphatic fluid
    1. Surrounds vestibular apparatus (semicircular canals and otolithic organs)
    2. Communicates with the perilymph of the Cochlea (from oval window to round window)
    3. Communicates with perilymphatic duct (and the subarachnoid space)

IV. References

  1. Goldberg (2014) Clinical Physiology, Medmaster, Miami, p. 118-9

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Related Studies

Ontology: Hearing (C0018767)

Definition (MSH) The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.
Definition (ICF) Sensory functions relating to sensing the presence of sounds and discriminating the location, pitch, loudness and quality of sounds.
Definition (ICF-CY) Sensory functions relating to sensing the presence of sounds and discriminating the location, pitch, loudness and quality of sounds.
Definition (OMS) Perception of sound by the ears.
Definition (NCI) The auditory faculty, the perception of sound by the ear.
Definition (CSP) process whereby auditory stimuli are selected, organized and interpreted by the organism.
Definition (CSP) sensation of sound.
Definition (GO) The series of events required for an organism to receive an auditory stimulus, convert it to a molecular signal, and recognize and characterize the signal. Sonic stimuli are detected in the form of vibrations and are processed to form a sound. [GOC:ai]
Concepts Physiologic Function (T039)
MSH D006309
SnomedCT 47078008, 128541009
LNC LP30518-2, MTHU015042
English Hearing, perception of sound, sensory perception of sound, Hearing, function, sound perception, auditory sense, hearing perception, Audition, Hearing functions, unspecified, Hearing functions, auditory functions, hearing, hear, hears, auditory senses, auditory function, audition, Auditory function (observable entity), Perception of sound, Hearing, function (observable entity), Auditory function, Audition, NOS, Hearing, NOS, Hearing (function)
Swedish Hörsel
Czech sluch
Finnish Kuulo
Russian SLUKH, СЛУХ
Croatian SLUH
Polish Słuch
Japanese 聴くこと, 聴覚, 聴力
Norwegian Hørsel
Spanish función auditiva, función auditiva (concepto no activo), audición (entidad observable), audición (función), audición, sentido de la audición, Audición
German Hören
Italian Udito
Dutch Horen
Portuguese Audição
French Audition, Ouïe

Ontology: Hearing problem (C0260662)

Definition (CCC) Diminished ability to hear
Definition (NCI) A disorder characterized by the partial or complete loss of the ability to detect sounds due to damage to the ear structures or inability of the brain to properly interpret or process the auditory signals it receives from the anatomic structures of the ear.
Definition (MSH) Conditions that impair the transmission of auditory impulses and information from the level of the ear to the temporal cortices, including the sensorineural pathways.
Definition (PSY) Disorders involving the hearing mechanisms, specifically the sensorineural pathways.
Definition (CSP) conditions that impair the transmission or perception of auditory impulses and information from the level of the ear to the temporal cortices, including the sensorineural pathways.
Concepts Disease or Syndrome (T047)
MSH D006311
SnomedCT 128540005, 300228004, 362966006, 362989003
LNC MTHU013366
English Hearing Disorders, Hearing disorders, hearing disorder, HEARING DIS, Hearing problem, auditory system disorder, auditory disturbance, auditory effects, Auditory disorder, Auditory disorder (NOS), Auditory disorder NOS, Hearing Disorders [Disease/Finding], rndx auditory alteration, rndx auditory alteration (diagnosis), auditory defect, hear problem, problem hearing, auditory disorders, hear problems, disorders hearing, hearing disorders, Problem;hearing, auditory disturbances, auditory disorder, of hearing disorder, Impaired Ability to Hear, Auditory Alteration, Disorder of hearing, Disorder of auditory system (disorder), Disorder of auditory system, Hearing disorder, Hearing problem (finding), Auditory alteration, Auditory dysfunction (disorder), Auditory dysfunction, disorder; hearing, disturbance; hearing, hearing; disorder, hearing; problem, problem; hearing, Hearing Disorder, hearing problem, Hearing disorder (finding), Hearing disorder (disorder)
Spanish trastorno de la audición (trastorno), Trastorno auditivo, Trastorno auditivo (NEOM), Trastorno auditivo NEOM, trastorno de la audición (hallazgo), disfunción auditiva (trastorno), disfunción auditiva, problema auditivo (hallazgo), problema auditivo, trastorno auditivo, trastorno de la audición, trastorno del sistema auditivo (trastorno), trastorno del sistema auditivo, Trastornos de la audición, Trastornos de la Audición
Dutch gehoorsaandoening (NAO), gehoorsaandoening NAO, gehoorsaandoening, gehoor; probleem, gehoor; stoornis, probleem; gehoor, stoornis; gehoor, behalve doofheid en tinnitus, gehoorstoornissen, Gehoorstoornis, Gehoorstoornissen, Stoornis, gehoor-, Stoornissen, gehoor-
French Troubles auditifs SAI, Troubles auditifs, Troubles de l'audition
German Hoerstoerung (NNB), Hoerstoerung NNB, Hoerstoerung, Hoerstoerungen, Hörstörungen
Italian Disturbo dell'udito NAS, Disturbo dell'udito, Disturbo dell'udito (NAS), Disturbi dell'udito
Portuguese Perturbação auditiva, Perturbação auditiva NE, Perturbações da audição, Transtornos da Audição
Japanese 聴覚障害, 聴覚障害NOS, 聴覚障害(NOS), チョウカクショウガイ, チョウカクショウガイNOS, 聴力障害
Swedish Hörselskador
Finnish Kuuloviat
Russian SLUKHA RASSTROISTVA, SLUKHA POTERIA SMESHANNAIA, PROVODNIKOVO-NEIROSENSORNAIA, СЛУХА ПОТЕРЯ СМЕШАННАЯ, ПРОВОДНИКОВО-НЕЙРОСЕНСОРНАЯ, СЛУХА РАССТРОЙСТВА
Czech Porucha sluchu NOS, Poruchy sluchu, Porucha sluchu (NOS), Porucha sluchu, sluchové poruchy, poruchy sluchu, sluch - poruchy
Croatian SLUH, OŠTEĆENJA
Polish Zaburzenia słuchu
Hungarian hallási rendellenesség, Hallás betegségei, Hallási rendellenesség k.m.n., hallási rendellenesség (k.m.n.)
Norwegian Hørselsskader, Hørselsforstyrrelser