The Secret of Hearing- Know All That Happens inside your EAR
What comes as a second nature to most of us becomes a concept of awe and confusion to people who don’t have that privilege. While this sentence can be true in a lot of contexts, today we are going to talk about the human ear and the secret of hearing- the very functioning of the small biological part of our body that plays an unparalleled role in the functioning of our day to day life.
To begin with, let us try and understand what the human ear does. The human ear transcends sounds and sends it across to the brain which further gives the signals to your auditory nerve to hear whatever sounds you are able to listen to. This function might sound simple but involves a lot of science behind it which we will cover in this blog. Interestingly, the ear doesn’t just help you to hear but also to maintain a sense of balance.Though these two might be considered the direct functions of the human ear, the indirect function, surprisingly includes speaking. The idea of speech only comes with the idea of listening. From the very birth, a child is trained to speak by listening to the sounds around him/her right from the sounds of parents to the surroundings to the toys the child plays with; everything becomes a contributing factor as to when the child begins to speak.
Now that you have a fair idea of what the ear does, let us get into the details of how it does what it does or in other words, the biological parts of the ear and what goes on inside it. Categorically speaking, the human ear can be divided into three parts-
- The Outer Ear
- The Middle Ear
- The Inner Ear
Let’s try to understand them one by one. The outer ear contains the visible portion of the ear also called the auricle or pinna. The auricle begins from the side of the head and goes till the eardrum which is the part of the middle ear. Auricle helps in collecting sound waves and guiding them internally to the eardrum. The middle ear, on the other hand, is a narrow cavity filled with air located in the temporal bone. It has three tiny bones, namely, the malleus (hammer), the incus (anvil) and the stapes (stirrup). These are collectively called the auditory ossicles which help in transmission of sound waves to the inner ear.
The inner ear works on a complicated system of fluid filled cavities which are all located deep inside the petrous portion of the temporal bone. The inner ear is subdivided into two units- the vestibular apparatus and the cochlea. The vestibular apparatus further consists of the vestibule and semicircular canals. These two canals have the organs of postural equilibrium which helps in maintaining the balance. The cochlea is a snail-like structure which contains the sensory organ of hearing. The sensory organs have a number of nerve endings of the eighth cranial nerve which is also called the vestibulocochlear nerve.
The division of the ear into three parts is just for the convenience of understanding. The human ear is obviously one entire organ without any physical divisions.
The Process of Hearing
Hearing is a process by which the human ear receives the sounds from the external environment and converts it into vibrations, sending signals to the brain where the vibrations are interpreted as sounds. The intensity of sound is measured and reported in decibels (dB), a unit that expresses the relative magnitude of a sound on a logarithmic scale.
The Human Ear is a very advanced organ present in all mammals. The sound waves enter the outer ear and travel through the ear canal, reaching the eardrum[Tympanic membrane] and inturn causing the auditory ossicles to vibrate. The motion of the stapes sets up waves in the fluids of the cochlea causing the inner membrane to vibrate. These vibrations in turn stimulate the sensory cells of the Organ of Corti,, which sends impulses to the brain.
Ears are delicate organs that can be damaged by physical injuries, bacteria or even changes in the environment. Ear infections are the most common disease of the human ear followed by hearing loss nowadays.
According to reports one in every six persons today, suffers from partial or total hearing loss. Stay tuned to know more about the human ear, its significance and the problems related to it. You would be surprised to know what all the tiny yet very important organs can do.