Hearing is apart of the five senses which makes it an essential part of everyday life. We go about our lives taking our sense of hearing for granted.
At any given point we could lose our hearing. This would leave us in a situation of non stop research of how we lost our hearing, why did it happen, and so on. It’s important for everyone to know the physiology and anatomy of the ears so they have a better understanding of what happening when they hear a sound or can’t hear a sound. Hearing is a process in which our ear converts sound vibrations in the external domain into nerve impulses that are transported to the brain. The brian than transforms those vibrations into sounds. Sounds are produced when a vibrating object creates a burst of vibrating air molecules, most commonly known as sound waves. Our ear can differentiate different aspects of a sound, such as the pitch, by analyzing different physical characteristics of the waves (https://www.britannica.
com/science/ear/The-physiology-of-hearing). Pitch is the understanding of the frequency of a sound wave. A frequency is the number of wavelengths that come together at a given point. Our ears most commonly hear a frequency of 1,000, to 4,000 hertz (https://www.britannica.com/science/ear/The-physiology-of-hearing).
The larger their amplitude, the greater the power of the sound will be. For sound to be transmitted to the central nervous system, energy will go through three transformations. The first transformation consists of the air vibrations that convert into vibrations of the tympanic membrane.
The second become vibrations in the fluid that is found within the cochlea. The last transformation allows fluid vibrations of traveling waves go near the basilar membrane and then revive the hair cells of the Corti. These cells convert sound vibrations into nerve impulses in the fibres of the cochlear nerve, then transfer them to the brainstem.
Once this is done they are passed on to the auditory section of the cerebral cortex, when this happens you, the listener will become mindful of the sounds that you are hearing. The three major regions of the ear consist of the outer ear, middle ear, and inner ear. The Outer ear consists of an ear canal.
The ear canal channels sounds and provides protection (https://www.healthline.com/human-body-maps/ear). The Pinna is known as the most visible part of the ear.
The middle ear has three tiny bones, the malleus, incus, and stapes. These three bones transfer sound vibrations from the eardrum to the inner part of the ear. The middle part of your ear is important because it allows for any infections to travel down a route, also known as air paths.
This now takes us to the inner ear. The inner ear has the most “action” going on. The proper name for the inner ear is known as the Labyrinth, which gives our body’s a sense of balance while also containing the hearing organ. The bony labyrinth and the membranous labyrinth make up the two main components of the inner ear. The hearing organ another name for the cochlea, is located inside the inner ear. The main hearing organ is located inside the cochlea duct. Sound waves move through the outer region to the middle and then flow to the inner region and its complex system.
There are six main different structures within the ear that help us hear. The first one is the External Ear Auricle. This structure directs sound into external acoustic meatus. Which leads us to the External Acoustic Meatus which leads the sound waves to the tympanic membrane. The Tympanic Membrane than vibrates when the sounds waves enter. They then move to the Tympanic Cavity which amplifies the vibrations that came from the Tympanic Membrane. From there it moves to the Auditory tube which levels the air pressure in the Tympanic Membrane.
Next the Cochlea carries the vibrations to the spinal organ (https://www.earthslab.com/physiology/location-structure-function-sensory-receptors-involved-hearing/#content-disorders-of-the-ear). All auditory messages are carried to brain by either the primary auditory pathway or the non-primary pathway. The primary auditory pathway carries messages from the cochlea while the non-primary pathways carries all different types of sensory messages (http://www.cochlea.eu/en/auditory-brain). There are 4 transmissions in the primary path and it ends in the primary auditory cortex.
The pathway starts in the cochlear nuclei, located in the brainstem. This is the first level of the pathway, it deals with decoding of a signal. The second level occurs in the superior olivary complex. In this level the auditory fibres cross the midline. In the third level it moves to the superior colliculus which plays a role in where the sound is. This then takes it to the last level and it occurs in the medial geniculate body. In the final level a preparation for a motor response starts occurring.
Finally it reaches the auditory cortex where the message is fully decoded and results in a voluntary response. The non-primary pathway functions by choosing a sensory message to be viewed first. It all starts in the cochlear nuclei and then moves to the reticular pathway in which a variety of synapses transpire. Auditory information is mixed with other sensory styles and is triaged into the highest priority (http://www.cochlea.eu/en/auditory-brain).
After this occurs the pathway than leads to the non-specific thalamus and then to the polysensory cortex. Deafness is either always a partial or total loss of hearing. This happens when the cochlear hair cells are damaged by intensified sounds. Disorders of sound by the tympanic membrane cause conduction deafness, which may be controlled by the use of hearing aids (https://www.earthslab.com/physiology/location-structure-function-sensory-receptors-involved-hearing/#content-disorders-of-the-ear). Some infections that may lead to hearing loss or are caused by hearing loss include Labyrinthine and Otitis media.
Labyrinthine is a disease of the internal ear and produces symptoms of nausea, ringing in the ears, and hearing loss. It is possibly caused by infection, aging, or trauma circulation disorder. Otitis media is an acute infection of the tympanic cavity. It causes severe pain.
Pathogens enter in the middle ear, young children are more likely to get this infection because their auditory tubes are short and horizontal, this allows for the spreading of bacteria from the pharynx to the tympanic cavity (https://www.earthslab.com/physiology/location-structure-function-sensory-receptors-involved-hearing/#content-disorders-of-the-ear).
Knowing the background information of how your ears work is important because it gives you information you never would’ve thought of before. It allows for a person to understand how they hear the sounds they hear everyday. Hearing is important to a person’s well being because it empowers us, allows us to communicate with others, keeps us safe by letting us know of any potential danger.
Knowing all the different parts of the ear that contribute to us hearing sounds helps because it provides us with information that may be useful one day when our ears don’t work anymore.
