Basics of Sound and Human Hearing

These flashcards cover the basics of sound, human hearing anatomy, auditory pathways, mechanisms of sound perception, and types of deafness.

What is the definition of Hertz (Hz) in sound?

Cycles per second of sound, perceived as pitch.

What does Amplitude refer to in sound?

Intensity, perceived as loudness.

What is a Pure Tone?

The tone of a single frequency of vibration.

What is the Absolute range of human hearing?

20-20,000 Hz.

Which frequency range is most sensitive for human hearing?

2,000-5,000 Hz.

What are the three parts of the ear?

Outer ear, Middle ear, Inner ear.

What structures are included in the Outer ear?

Pinna (auricle), Ear canal, Tympanic membrane (eardrum).

What is the role of the Ossicles in the Middle ear?

They transmit sound vibrations from the eardrum to the inner ear.

How do the muscles in the Middle ear protect from loud noises?

By stiffening the eardrum.

What is the sequence of vibration travel through the ear?

Eardrum → Ossicles → Oval window → Endolymph (fluid in cochlea).

What is the function of the cochlea?

Activates different parts based on vibrations and sends info to the cochlear nerve.

What happens to auditory hair cells during vibrations?

Stereocilia bend, opening ion channels which leads to depolarization and glutamate release.

What part of the auditory pathway allows for binaural input processing?

Superior olive.

What is tonotopic organization in the Auditory cortex?

The ordering of the auditory cortex by tone; highest frequencies are located in the back and inner part.

What are the two ways we hear pitch?

Frequency coding and Place coding.

Which mechanism is used for low frequencies (<1000 Hz)?

Frequency coding.

How do intermediate frequencies (1000-5000 Hz) use auditory coding?

Using volley and place coding.

What are binaural cues used for?

Determining the direction a sound is coming from.

What does the Dorsal stream in the auditory cortex represent?

The 'where' pathway (location of sound).

What is Central deafness caused by?

Brain lesions.

What is Conduction deafness?

When sound waves are prevented from reaching the cochlea.

What causes Sensorineural deafness?

Cochlea or auditory nerve lesions.

What is tinnitus?

Chronic ringing in the ear caused by cochlear damages.