C8- Acoustic system

The somatic sensory system allows for perception of our immediate surroundings, while special senses like vision and hearing allow for perception from a distance.

Sound waves are created by the vibration of air molecules, resulting in alternating regions of compression and rarefaction.

The process of interpreting sound involves two key aspects: identifying what the sound is and where it's coming from.

Sound intensity, measured in decibels (dB), is determined by the amplitude of the sound wave.

The pitch of a sound is determined by the frequency of the sound wave.

The timbre of a sound refers to its unique quality or characteristic sound, determined by additional overtones present in the wave.

The fundamental frequency (FF) is the dominant wave in a complex sound, determining its pitch.

Overtones are additional frequencies present in a complex sound, superimposed on the fundamental frequency, contributing to timbre.

The unique quality or characteristic sound of a sound wave, determined by the presence of additional overtones (frequencies) superimposed on the fundamental frequency.

The process of converting sound waves into electrical signals that the brain can interpret.

The part of the ear responsible for amplifying sound waves, protecting the ear from loud noises, and transmitting vibrations to the inner ear.

The ability to distinguish the source of a sound.

The process of gathering sound energy and focusing it on the eardrum.

The outer ear, middle ear, inner ear, superior olive, and auditory cortex.

Frequencies that are higher than the range of human hearing (above 20,000 Hz).

The range of frequencies that humans can detect (20 Hz to 20,000 Hz).

Frequencies that are lower than the range of human hearing (below 20 Hz).

A small, coiled structure in the inner ear that converts sound vibrations into electrical signals the brain can understand.

The thin membrane inside the cochlea that vibrates at different frequencies, allowing us to distinguish between different sounds.

The fluid-filled chambers on either side of the cochlear partition in the inner ear.

A distinct channel located within the cochlear partition that contains fluid called endolymph, essential for proper cochlear function.

The opening at the apex of the cochlea that connects the scala vestibuli and scala tympani, allowing their fluid to mix.

The fluid found in the scala vestibuli and scala tympani, crucial for sound transmission.

A membrane that covers the oval window, which transmits vibrations from the stapes to the fluid in the cochlea.

A membrane that covers the round window, acts as a pressure release valve for the fluid in the cochlea.

The process through which the inner ear amplifies sound waves, taking them from the oval window, through the fluid, and to the basilar membrane.

The process of converting sound vibrations into electrical signals that the brain can interpret.

The external ear amplifies sound frequencies around 3kHz due to the resonance of the auditory meatus, which is the channel leading to the eardrum.

The shape of the pinna (outer ear) and concha (ear cavity) filters different sound frequencies, providing spatial cues about the location of sound sources.

The middle ear transmits sound vibrations from the air to the fluid-filled inner ear, compensating for energy loss.

The three tiny bones in the middle ear (malleus, incus, and stapes) amplify sound vibrations by a factor of 20.

The tensor tympani muscle, attached to the malleus, and the stapedius muscle, attached to the stapes, protect the inner ear from loud noises.

This protective reflex stiffens the ossicles, reducing sound amplification and protecting the inner ear.

The oval window is a membrane-covered opening that transmits sound vibrations from the stapes into the inner ear.

The Eustachian tube connects the middle ear to the nasopharynx, allowing pressure equalization.

The round window is another membrane-covered opening in the middle ear that releases excess pressure.

The mastoid air cells are connected to the middle ear, contributing to its ventilation and pressure regulation.

The ability of the auditory system to distinguish the unique color or quality of a sound, determined by the presence of overtones, or additional frequencies, present in the complex sound wave.

The basilar membrane is a flexible structure within the cochlea that vibrates at different points along its length depending on the frequency of the sound. Different locations along the basilar membrane correspond to different frequencies, allowing the brain to identify pitch.

The Organ of Corti is a specialized structure located within the cochlea, serving as the sensory organ for hearing. Hair cells, which are not neurons, are responsible for converting mechanical vibrations into electrical signals.

The bending of stereocilia, tiny hair-like processes on the top of hair cells, triggers the release of neurotransmitters, initiating the process of converting mechanical vibrations into electrical signals.

The overlying tectorial membrane, anchored differently than the basilar membrane, creates a shearing motion when the basilar membrane vibrates. This shearing motion bends the stereocilia on the hair cells, triggering the process of transduction.