Why is my grandpa always asking me to raise my voice? Why can’t he hear my voice unless I raise it? Is he having a problem with his ears, or is it a normal thing that naturally happens as we age?
That’s our topic for today; we will answer all the questions above. But more importantly, we will talk about our ears in detail: the complex structure of our ears, the function of our ears, how we hear, and some problems that might affect our ears. At the end of this article, you will find a list of some tips to help you take care of your ears.
Here’s a list of the main items discussed in this article for easier navigation:
Table of content:
- The structure of the ear.
- The outer ear.
- The middle ear.
- The inner ear.
- Functions of the ear.
- How do we hear?
- Some problems that might affect your ears.
- Ear infections.
- Swimmer’s ear.
- Meniere’s disease.
- Ruptured eardrum.
- Eustachian tube dysfunction.
- How to take care of your ears.
The Structure of Our Ears
When referring to the ear, we don’t talk about the part that you see on the sides of your face only. Your ear is way larger and more complex than you might have imagined. Each ear is divided into three parts according to their place as follows:
- The outer ear
- The middle ear
- The inner ear
So let’s talk about each segment in more detail, starting from the outer part (outer ear) and then going deeper inside your skull till we reach the inner ear.
1. The Outer Ear
This is the outer visible part of your ear. It includes two main structures:
The pinna (auricle).
It is made up of skin and cartilage. It collects sound waves, which then pass to the next station, the External Auditory Canal.
The external auditory canal.
This is a canal that you can see with your eye. This canal is kept open because of its lining cartilage in the first part and bone in the final part. Be careful not to stick anything in that canal since this canal ends by your eardrum, which is a vital structure in the hearing process that you don’t want to lose.
2. The Middle Ear
This is the middle part which lies between your inner and outer ear. It is an air-filled cavity which is sometimes called the tympanic cavity. It is separated from the external auditory canal by the eardrum (also referred to as the tympanic membrane). It contains three tiny bones (ossicles) in its cavity, which are named after their shapes as follows:
- Malleus (the hammer): this is the first small bone you see if you look at the middle ear from the outside. It is attached to your eardrum.
- Incus (the anvil): this is the middle ossicle. It lies between the malleus and stapes.
- Stapes (the stirrup): the last ossicle in your middle ear, which is attached to the incus at one end and to the inner ear at the other end. It connects with the inner ear through a structure known as the oval window. The oval window is thus the structure that connects your middle ear to the inner ear.
These tiny ossicles play a major role in the amplification of sound before it is transmitted to your inner ear.
Your Middle Ear cavity is connected to your pharynx (upper throat) through a structure known as the Eustachian tube. This tube is crucially important for equalizing the pressure between the air inside your middle ear and that outside your ear (atmospheric). Any imbalance between the two pressures can lead to disastrous consequences, such as a rupture in your eardrum.
3. The Inner Ear (The Labyrinth)
This is the deepest part of your ear where the actual organ of hearing lies, that is, the cochlea. There is also another structure attached to your cochlea that is responsible for keeping your balance, which is called the vestibular system.
It is a snail-shaped structure that is filled with fluid that moves on receiving vibrations from the oval window. It is lined by tiny sensory cells inside its cavity, known as hair cells. These hair cells are responsible for transforming the vibration signal they receive into an electrical signal that then travels along the auditory nerve to the brain. They do so by releasing a chemical substance that activates the nerve fibres attached to the base of these hair cells.
The vestibular system.
Like the cochlea, the vestibular system is a fluid-filled cavity inside your inner ear. This system is responsible for keeping your body balanced. It consists of two structures:
- Three semicircular canals: they are located in three different planes, with each canal making an angle of 90 degrees with the other one. These canals contain cells that can detect angular acceleration of your head.
- The utricle and saccule: they contain cells that can detect linear acceleration of your head.
The fluid inside your semicircular canals starts to move when your head moves. This leads to the activation of hair-like cells inside these canals, which transform this information into electrical signals. These signals are then transmitted to your brain through the vestibular nerve. Your brain then translates these signals about your body position and movement and sends back signals to your muscles to keep your body balanced and help you adjust your posture accordingly.
That’s why dizziness and trouble maintaining your balance are common symptoms of this system impairment.
The Functions of Our Ears
You may have already guessed the two main functions of your ear based on their structure, as mentioned above. That’s right, your ear has two main functions, which are hearing and balance. The organ dedicated to the hearing function is the cochlea, while your vestibular system is responsible for detecting the position and movement of your head in space to help you stay in balance.
The Mechanism of Hearing
We are ready to talk about how we hear after seeing the different parts of our ears. So here’s how sound travels inside your ear:
- Sound waves travel through your external auditory canal after being collected by your ear pinna.
- They then hit your eardrum and cause it to vibrate.
- This vibration is then transmitted to the tiny bones inside the cavity of your middle ear (ossicles).
- Since these ossicles are attached to your inner ear, they transmit these vibrations to the inner ear where the actual organ of hearing (cochlea) lies.
- Inside the cochlea, tiny hair cells transform these vibrations into electrical signals and send them along nerve fibres attached to their base.
- These signals then travel along the auditory nerve to the brain.
- Your brain then decodes these signals to help you perceive that sound and obtain meaningful information about it; is it loud or quiet? Is it my mom’s voice or my friend’s? Is it my favourite piece of music? Oh, that’s my WhatsApp notification sound.
Here’s a fun animation video that shows you how we hear in just two minutes.
Problems That Might Affect Your Ear
Your ears might be affected by several conditions. In this section, we talk about some diseases that might affect your ears. Some of these conditions might affect your hearing but not all of them. That’s why it’s always better to visit your doctor whenever you develop any abnormal symptoms.
An ear infection is a term that usually refers to an infection of the middle ear (otitis media) since it’s the most common type. It is more common in children than adults. It is usually caused by bacteria or viruses that come from a respiratory tract infection, like a common cold. This infection finds its way to the middle ear through the eustachian tube, which has its opening in the upper throat (pharynx).
That is the annoying hissing or buzzing sound you might hear in one or both ears. It becomes most noticeable in silence, and that is exactly why it’s more common in deaf people. It usually comes in two types:
- Subjective tinnitus: this is the type of tinnitus that can be heard only by the patient, and the doctor can’t find solid evidence for it.
- Objective tinnitus: this is the type that can be perceived by both the patient and the doctor.
Also called otitis externa, that’s because it’s an infection of the external auditory canal. It is called swimmer’s ear because it usually occurs in people who swim in improperly treated water (dirty water) which allows bacteria and other organisms to get into your ear canal and cause infection. This does not mean it happens only to swimmers since it can happen to anyone else if they apply any irritant substance inside their ear canal.
This is a chronic condition in which the fluid that fills your inner ear structures (cochlea and vestibular system) starts to build up over time. The causative agent of this disorder is still unknown. People with this condition often complain of dizziness, vertigo, tinnitus, and a sense of fullness inside their ears.
Your eardrum might rupture for different reasons, like introducing a foreign object inside your ear canal, which ends with your eardrum. This creates a hole inside your eardrum (tympanic membrane). This hole can heal on its own, especially if small. However, if large, it may require surgical repair.
Eustachian tube dysfunction
We have already talked about your eustachian tube and how it works to equalize air pressure between your middle ear and that of the outer ear (atmospheric air). The eustachian tube opens when you yawn, sneeze, or swallow to equalize that pressure. That’s why if you are flying on a plane, some people might advise you to chew gums. This will open your eustachian tube and equalize air pressures that normally change as you fly and land.
In case your eustachian tubes get clogged and couldn’t open (eustachian tube dysfunction), this will make it harder to equalize air pressures. This may lead to tinnitus, muffled hearing sensation, a sense of ear fullness and, in severe cases, ear pain.
Now, it’s time to give an answer to our first question in this article. This condition (Presbycusis) is a hearing difficulty that occurs in many people above the age of 65. It is a gradual age-related hearing loss in both ears. It is a very common problem that occurs gradually as we age.
So don’t worry; your grandpa is fine, and you will most probably get it as you age, too. It’s not a complete hearing loss but rather a mild decline in hearing that many of us will experience as we grow older.
How to Take Care of Your Ears
Here’s a list of some tips that you can apply to keep your ears healthy:
- Avoid prolonged use of headphones.
- Protect your ears with earplugs if you are around loud noises or you work in a noisy environment (you are working in construction).
- You should also wear earplugs during swimming to keep them dry and prevent infection.
- Avoid cleaning your ear canal with cotton swabs or any other objects since you might perforate your ear drum. These things have been confirmed to cause more harm by pushing the ear wax deeper inside your ear canal.
- When listening to music or watching TV, it is better to turn down the volume.
- Always visit your healthcare provider if you develop any abnormal symptoms.
That was our topic for today; we talked about our ears, their internal structure, how hearing works, some conditions that might affect your ears, and finally, how to take care of your ears.
We hope you found this article informative, and if so, you will find similar articles on our website that talk about different body parts like your heart, nose, eyes, urinary system, skeletal system, cardiovascular system, respiratory system, and much more. So take a deep dive into it and enjoy reading.
The main references used in this article:
- Johns Hopkins Medicine, How the Ear Works.
- Kenhub, Vestibular system.
- How does the ear work?
- Cleveland Clinic, Ear.
- How Do We Hear?
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