The process by which sounds in our environment are collected, translated into nerve signals, and interpreted by our brains is nothing short of incredible. Hearing loss can arise from an issue in any part of this hearing sequence, and it’s helpful to understand the mechanisms underlying it. At Applied Hearing Solutions, we believe that educating patients on every facet of hearing loss leads to the most appropriate hearing treatment available.
Sound waves begin by entering your outer ear, called the pinna. It funnels these waves through your ear canal and into your middle ear, which are separated by the tympanic membrane, also known as the eardrum. This flexible membrane begins to move when sound vibrations hit it, which in turn starts to move the ossicles—the three small bones in the middle ear: the malleus (hammer), incus (anvil), and stapes (stirrup). These bones work together to amplify the sound waves and move them to your inner ear. The middle ear is often where hearing loss begins to occur, so it’s important that all of these moving parts are free of damage.
The inner ear is full of fine hair-like cells, replete with nerve endings, within a spiral-shaped organ called the cochlea. These tiny hair cells collect information from sound vibrations coming in from the middle ear and transmit those vibrations into nerve impulses, via the auditory nerve, to your brain. The brain processes and interprets these nerve impulses as sound in the auditory cortex, allowing us to hear sounds around us.
If you are experiencing hearing loss, it means that one of the above sections isn’t working correctly. Our hearing evaluation is designed to diagnose which type of hearing loss is present, and enables us to offer a range of treatment plans that are most appropriate for you.
Now that you understand how a healthy ear functions, let’s discover the three types of hearing loss and how they are caused.
Sensorineural hearing loss is the most common type of hearing loss and is the result of a problem in the inner ear or auditory nerve. It occurs when the tiny hair-like cells in the cochlea and/or the auditory nerve are missing or damaged, as both result in weakened nerve signals being sent to the brain.
Common causes of sensorineural hearing loss are:
Conductive hearing loss results from a problem in the outer or middle ear that prevents sound from reaching the inner ear. Conductive hearing losses are relatively uncommon and are typically temporary. Most cases of conductive hearing loss can be treated with medication or surgery. When it cannot be treated with those means, most people benefit from the use of a hearing aid.
Common causes of conductive hearing loss are:
Mixed hearing loss is a combination of conductive hearing loss and sensorineural hearing loss. When there is damage to either the outer or middle ear and the inner ear or auditory nerve, mixed hearing loss occurs.
The sensorineural hearing loss is permanent while the conductive hearing loss may be reversible. Mixed hearing loss typically occurs when the ear sustains some type of trauma or injury, but can also result from a combination of the possible causes listed above. Learn more about causes of hearing loss.
It seems like we all know someone who has hearing loss—whether or not that someone has started treating their hearing loss is another story. But why is this? The impact of unaddressed hearing loss influences almost every aspect of the human experience. It can negatively affect aspects of our communication, cognition, education, and social life. Hearing loss is a pervasive problem. It affects approximately 430 million people worldwide, including 50 million individuals in the United States alone.
Did you know?
Early identification is essential. Schedule a comprehensive hearing evaluation with an audiologist near you to learn more about your hearing status. Effective management could reduce the long-term effects of the adverse impacts associated with hearing loss.
You know the old saying: “if a tree falls in the woods and no one is around to hear it, does it still make a sound?” Well, the short answer is…yes it does. Let me explain why.
Humans hear in a series of simple steps in which sound waves from the air are converted into electrical signals sent up to our brain. To better understand this process, you have to understand the anatomy and physiology or your ears. There are three main components of the peripheral hearing system (AKA the human ear)—the outer, middle, and inner ear.
Outer ear. The outer ear contains the pinna, ear canal, and eardrum. Sound waves are really just vibrations in the air around us. These vibrations enter the outer ear, funnel down the ear canal, and make the eardrum vibrate.
Middle ear. This air-filled cavity is home to the three smallest bones in your body—the malleus, incus, and stapes. Vibrations from the eardrum are sent down a chain created middle ear bones. These bones amplify the sound vibrations and send them to the cochlea.
Inner ear. Your inner ear contains the cochlea, which is your hearing organ. The cochlea is a snail-shaped structure filled with fluid. Inside of that fluid is a membrane that moves up and down in response to the vibrations sent from the middle ear bones. Along that membrane, there are tiny microscopic hair cells. These hair cells detect the sound wave vibrations travelling along the membrane and convert them into electrical impulses. The auditory nerve carries that electrical signal up to the brain where the sound is actually heard.
That is the process of how a human hears. To bring it back to the story about the tree, sound is simply a vibration. This vibration of sound can travel through Water, Solids, or Air. However, in order for that sound to be heard, particularly by a human, the vibration will have to travel through our auditory system.