Praktikum hearing 01: Bagaimana kita bisa mendengar suara?

Summary

This video script introduces a hearing test practical, starting with a refresher on the physiology of hearing. It explains how sound waves are captured by the auricle and transmitted through the auditory canal, vibrating the eardrum and ossicles (malleus, incus, stapes). The vibrations then travel through the inner ear's cochlea, creating nerve impulses that reach the brain, enabling sound perception. The script details the three types of sound conduction: ossicular, air, and bone conduction, each contributing to the process of hearing, offering a thorough understanding of auditory physiology and its role in hearing tests.

Takeaways

• 😀 The hearing test practical session requires a solid understanding of auditory physiology.
• 😀 Sound waves that we can hear are first captured by the outer ear (auricle).
• 😀 The sound waves then travel through the external auditory canal to vibrate the eardrum (tympanic membrane).
• 😀 The vibration of the eardrum moves the auditory ossicles: malleus, incus, and stapes.
• 😀 The stapes' vibrations reach the oval window (fenestra ovalis) in the inner ear.
• 😀 The vibrations from the oval window propagate through the cochlea’s vestibular and tympanic scalae.
• 😀 These vibrations deform the hair cells in the cochlea, generating nerve impulses.
• 😀 The generated nerve impulses are sent to the brain, allowing us to perceive sound.
• 😀 There are three types of sound conduction: ossicular conduction, air conduction, and bone conduction.
• 😀 Ossicular conduction involves sound waves vibrating the ossicles in the middle ear.
• 😀 Air conduction involves sound waves vibrating the tympanic membrane and causing further vibrations in the inner ear.
• 😀 Bone conduction involves sound waves directly vibrating the bones of the skull, reaching the inner ear.

Q & A

What is the first step in the process of hearing?

The first step in the hearing process is the auricle (outer ear) capturing sound waves.

How does sound travel through the ear after being captured by the auricle?

After being captured by the auricle, sound waves travel through the external auditory canal (canalis auditorius externus) and vibrate the tympanic membrane (eardrum).

What happens after the tympanic membrane vibrates?

Once the tympanic membrane vibrates, it causes the ossicles—malleus, incus, and stapes—to vibrate, transmitting the sound further into the ear.

What is the role of the stapes in the hearing process?

The stapes vibrates the oval window (fenestra ovalis), which leads to the transmission of sound vibrations through the cochlea and the inner ear.

How do sound waves travel within the cochlea?

Sound vibrations travel through the three scalae of the cochlea—scala vestibuli, scala tympani, and scala media—causing changes in the hair cells that eventually generate nerve impulses.

What happens when the hair cells in the cochlea are affected by sound vibrations?

The deformation of the hair cells in the cochlea leads to the generation of nerve impulses, which are then transmitted to the brain for sound perception.

What are the three main methods of sound conduction in the ear?

The three main methods of sound conduction are ossicular conduction, air conduction, and bone conduction.

What is ossicular conduction?

Ossicular conduction refers to the transmission of sound vibrations through the ossicles (malleus, incus, and stapes) in the middle ear to the cochlea in the inner ear.

How does air conduction work in the ear?

In air conduction, sound waves first vibrate the tympanic membrane, then transfer the vibration to the secondary tympanic membrane, leading to changes in the cochlea.

What happens during bone conduction?

During bone conduction, sound vibrations directly stimulate the bones of the skull, which then pass the vibrations to the inner ear, bypassing the middle ear.