Hearing loss is a serious problem that affects a person not only at the physiological level but at the psychological level as well. Do you know that your hearing loss can cause balance problems? Yes, you heard it right! The ear is a very complex organ. We know that the human ear is responsible for processing the sound signals and sending them to the brain, thus enabling us to ‘hear’, but the less known fact is that it is also responsible for maintaining the balance of the human body.
Hearing loss is often linked to balance disorders. Studies show that treating hearing problems - either with the help of hearing aids or other devices or medications - can reduce the risks of falling to a great extent, especially in older people.
The Balance Mechanism of the Human Body
Before discussing how the ears are responsible for maintaining the body balance, let us see how the whole balance mechanism works.
The sense of balance, technically known as equilibrioception, is one of the physiological senses related to balance. In short, it is a mechanism which prevents human beings and animals from falling while standing or moving. But behind this apparently-simple phenomenon, there is a complex process of several systems working together.
The balance mechanism of the human body works in strong coordination of several organs and systems. It works in a constant process of position detection, feedback and adjustment, with the use of communication and coordination between the inner ear, eyes, muscles, joints and the brain.
First and foremost, let us discuss the mechanism of the human ear. The ear comprises three main parts -
The outer ear
The middle ear
The inner ear
The inner ear serves two main functions - a) one part of it enables us to hear, and b) the second part, known as the vestibular system, is responsible for maintaining the body balance. The latter part, about which we are concerned right now, is designed to send information about the position of the head in a given point of time, to the centre of the brain which controls movement - that is the cerebellum.
What is the Function of the Cerebellum?
The cerebellum is a small part of the brain situated at the back of the head, where it meets the spine. The cerebellum is primarily responsible for coordinating voluntary movements such as body posture, balance, body coordination and speech, thus maintaining in a smooth and balanced muscular activity.
The cerebellum receives information in the form of signals about the body’s position from the inner ear, the eyes, muscles and joints. The cerebellum after understanding the meanings of these signals further sends messages to the muscles to make any positional adjustments necessary to maintain the body balance, thus ensuring that the individual does not fall while making any movements. The cerebellum is also responsible for coordinating the timing as well as the force of the muscle and joint movements which are initiated by other parts of the brain.
What is the Significance of the Vestibular System?
The vestibular system, seen in most of the mammals, is a sensory system, is responsible for maintaining the body’s balance, movement and equilibrium. It contributes to the sense of balance and spatial orientation, thus enabling smooth coordination of movement with balance.
A vestibule, which is oval-shaped, is referred to the central part of the bony counterpart in the inner ear. It is situated medial to the eardrum or the tympanic membrane, behind the cochlea and in front of the three semicircular canals (the horizontal, the superior and the posterior).
There is a structure in the inner ear, called the labyrinth, which is responsible for the body’s sense of balance. As the name suggests, it is a maze-like complex structure which is a combination of tissues and bones and is very delicate. The labyrinth comprises the semicircular canals and the otolithic organs.
Any movement is composed of two phases - rotations and translations. The vestibular system is therefore designed to control these two aspects, and thus comprises two components - the semicircular canals, which indicate the rotational movements, and the otoliths, which indicate the linear accelerations. The vestibular system after receiving these signals about the type of movement made by an individual, transfers them to the neural structures which control the eye movements, as well as to the muscles which control the individual’s posture, thus helping him/her to stay upright.
The brain then receives these useful information about the person's position and movements from the vestibular system, and enables an individual to understand his/her position and acceleration (that is the dynamics and the kinematics of his or her body) each and every moment, especially when there is a change in the body position and movement.
The semicircular canals are the main tools which detect the rotational movements. Since the world is three-dimensional, the vestibular system contains three semicircular canals in each of the labyrinth, placed at right angles to each other. The bony labyrinth, which is located in the temporal bone (that which is situated at the sides and the base of the skull), is referred to the rigid and bony outer wall of the inner ear, which consists of three parts - the vestibule, the semicircular canals and the cochlea.
The three sections of the semicircular canals are known as the lateral, the anterior or the superior and the posterior or the inferior semicircular canal. The lateral is considered the horizontal semicircular canal, and the anterior and the posterior are collectively known as the vertical semicircular canals.
Each of the semicircular canals consists of a fluid called perilymph. While the movement of the fluid present inside the horizontal semicircular canal corresponds to that of the rotation of the head around the neck - which acts as a vertical axis, the movement of the fluid inside the vertical semicircular canals corresponds to the movement of the head along the sagittal plane, which is felt during nodding, and in the frontal plane, which occurs during cartwheeling.
The second part of the vestibular system, that is the otolithic organs are responsible for sensing the linear accelerations. The otoliths enhance the sense of gravity and motion in an individual, by adding to the weight and inertia of the otolithic membrane.
All of these mechanisms contribute to the experience of equilibrioception in an individual, that is having a sense of balance and spatial orientation. It is due to the vestibular system that we experience the sense of self-motion. For example, if you are sitting in a chair in a dark room and if your chair is turned to the left, you will be able to realise that you have been moved to the left side - even if you are not able to see it. Similar is the case if you are in an elevator - such as you will be able to realise that you are descending if the elevator descends.
The vestibular system and the visual system work together to maintain the body position and posture of an individual with respect to the gravity of the earth. The muscles and the joints on receiving instructions from the brain via special sensory receptors, help in keeping the body in an upright position.
What Happens if the Vestibular System Breaks Down?
Any disease caused to the vestibular system can lead to vertigo and instability or the loss of balance, sometimes even accompanied by nausea or vomiting tendency. If the vestibular system and the visual system fail to work in coordination with each other, such as in a case in which the vestibular fails to report any movement while the visual system does, it leads to motion sickness. Any problems in the vestibular system cause balance problems, along with other conditions like vertigo, dizziness, nausea, diarrhoea fluctuating heart rate, blood pressure changes, anxiety or depression.
Symptoms of Balance Problems
Let’s brief up the common symptoms of balance disorders -
Having a sensation of motion or spinning like dizziness or vertigo
Increased risks of falling or having the feeling as if you are going to fall
Staggering while walking or moving unsteadily
Confusion or disorientation
Having a sensation of lightheadedness, faintness, or floating
Vision changes such as blurriness
Look up for more valuable information in this link: https://www.nidcd.nih.gov/health/balance-disorders
Does Hearing Loss Affect Balance?
Hearing loss by itself does not cause balance problems, but if there are any problems in the inner ear, the vestibular system might get affected. This means that hearing loss might occur together with the symptoms of balance problems since the inner ear is responsible for both hearing and maintaining body balance. Certain common inner ear or other health conditions are also associated with balance issues, vertigo which includes -
Otosclerosis of the middle ear
Ear infections, like labyrinthitis
In these cases, balance problems can be accompanied by hearing loss.
Can Hearing Aids Help Manage Balance Disorders?
People with hearing loss often find that wearing hearing aids can equalize hearing in both the ears and make you have a feeling of a natural and balanced hearing. This lessens the symptoms of balance problems such as vertigo or dizziness, risks of falling and disorientation. Additionally, hearing aids can also help reduce the impact of hearing loss to a great extent. Although this area of how far are hearing aids responsible in helping to manage with balance problems still needs proper research, yet the initial results are quite impressive and promising.
An interesting and proven fact is if the older people start wearing hearing aids instead of leaving their hearing loss untreated, their risks of falling reduces with a significant improvement in body balance and equilibrium. In short, an enhanced hearing makes way for maintaining proper body balance and posture.
According to the senior author Timothy E. Hullar, professor of otolaryngology at the School of Medicine, hearing aids allowed people to use the sound information coming from all the directions which acted as auditory reference points or landmarks which help to maintain balance.
Prof. Hullar compares it to our eyes when we use it to tell us where we are in space. If the lights are turned off, we tend to lose our balance a bit. Similar is the case with hearing and balance. Hearing properly can help you stay up without losing balance.
What are the Causes of Balance Disorders?
Although there can be numerous other causes of balance disorders apart from hearing loss, yet the ears play an active part in this system. The common factors that cause balance problems include -
Head or neck injuries
Blood circulation problems in the inner ear
Low blood pressure
Eye muscle imbalance
To determine the exact cause of balance disorders, consult an Audiologist, who would perform the necessary tests to determine whether there is a problem in the inner ear. He or she might also refer you to an ENT specialist to perform the necessary steps to analyse the cause of the problem and to determine whether there are any other conditions responsible for the balance problems.
So if you are facing any balance problems, do consider visiting a skilled and trained Audiologist and get your ears tested.
Do check out this link to learn more about balance disorders and their causes: https://www.mayoclinic.org/diseases-conditions/balance-problems/symptoms-causes/syc-20350474
We will add another blog about the tests done to diagnose balance problems.
Till then do let us know whether we missed out any fact.
Or are you aware of any other links between hearing loss and balance disorders?
We would like to know from you! Do share your valuable opinions in the comments below.