Hearing Loss and Audiology

Introduction

  • Focus on Exam Content and Remaining Schedule

    • Open with student sentiments about being stuck at a specific grade (A-).

    • Overview of upcoming lectures and final schedule.

    • Total of three more weeks of class.

Course Schedule

  • Week 1: Discuss hearing loss in the outer and middle ear.

  • Week 2: Discuss hearing loss in the inner ear.

  • Week 3: Discuss oral rehabilitation and deaf culture.

Understanding Sound Processing

  • Explanation of the auditory system.

    • Sound travels from the outer world into the brain.

    • Overview of the auditory pathway from outer ear to inner ear to brain.

  • Audiology: Importance of the field due to auditory pathway issues.

Outer and Middle Ear Disorders

  • Focus on what impedes sound transmission into inner ear.

  • Introduction to the topics of the lecture addressed, including medical conditions affecting hearing.

Assessment Details

  • Mention of quizzes:

    • Quiz on current week material scheduled for Friday.

    • Another quiz the following Friday.

    • Final Exam (Exam 4) summarizes the material from the last weeks of class.

    • Final only covers Chapters 15 & 16.

Importance of Medical Terminology

  • Discuss previous experience with medical terminology.

    • Importance of understanding root, prefix, and suffix components in forming medical words.

    • Breakdown of conditions discussed using terminology understanding is emphasized.

Auditory System Breakdown

  • Sound wave transmission through auditory system:

    • First Step of Sound Processing: Collection of vibrations in the ear.

    • The tympanic membrane's role in transmitting sound waves.

    • Bones of the middle ear function: Malleus, Incus, and Stapes.

Inner Ear Structure and Function

  • Fluid-Filled Inner Ear:

    • Role of fluid and movement due to stapes.

    • The impact of fluid on basilar membrane vibrations.

    • Vibration properties at different locations:

    • Base is narrow & stiff (high frequencies).

    • Apex is wide & flimsy (low frequencies).

Hair Cells Functionality

  • Inner and outer hair cells' roles:

    • Outer hair cells amplify signals.

    • Inner hair cells send action potentials to the auditory nerve.

Auditory Pathway

  • Transmission through the auditory nerve to the brain, through the brainstem, leading to sound recognition in the cortical area.

Conductive vs. Sensorineural Hearing Loss

  • Conductive Hearing Loss:

    • Result of blockage in outer or middle ear affecting transmission.

    • Issues such as blockage leading to weaker signals.

    • Example of using earplugs as a metaphor for blockage.

  • Sensorineural Hearing Loss:

    • Occurs when sound reaches the inner ear but fails to translate into electrical impulses.

    • Characteristics: difficulty hearing soft sounds, loud sounds may feel uncomfortable, and distortion of sounds.

Medical Conditions Impacting Hearing

  • Various potential hearing loss conditions discussed, including:

    • Otitis Externa: inflammation/infection in the outer ear (often from swimming).

    • Treatment includes antibiotics if bacterial infection present.

    • Exostosis: abnormal bone growth in ear canal, often seen in swimmers and surfers.

    • Microtia and Anotia: congenital conditions of small or absent ears, possibly resulting in conductive loss; surgical reconstruction methods discussed.

    • Hematoma Auris: common in wrestlers and fighters, induced by trauma leading to blood accumulation under skin; treatment involves draining fluid.