Introduction
It is common for a functional decline to occur as one age. Vision gets poor, hearing declines, and the brain becomes slow to process information. This, in turn, can impact one’s quality of life as a whole. There can be problems in communication; they may not enjoy the activities they once enjoyed and may have relationship issues. In some people, it can lead to a life of isolation. This article deals with the sensory changes that occur as one ages.
How Do Sensory Signals Work?
Generally, the sense organs help one to perceive the environment around them. Information in the form of sound, light, smells, tastes, and touch helps one to know what is happening around them. This sensory information gets translated into nerve signals that are sent to the brain. The brain interprets these information sensations. The body requires certain information to become aware of the sensation. The minimum amount of information the body requires to sense a piece of information is called the ‘threshold.’
What Are the Sensory Changes That Occur as One Age?
As one age, the ‘threshold’ also increases. One would require more information or more of the sensation to perceive it. All the senses are affected by aging. However, there are two senses most commonly affected. They are hearing and vision. Studies show that older adults have some kind of vision problem by the age of sixty-five and hearing issues by about seventy-five years of age. Some changes in the lifestyle or the use of aids like glasses or hearing aids can help to improve one’s perception of sight and hearing.
-
Hearing: The human ear has two functions. Hearing is the primary function; the second is maintaining body balance. The sound waves travel through the auditory canal to the eardrum and cause it to vibrate. These vibrations spread to the tiny bones in the middle ear and are passed to the auditory nerve. The auditory nerve is responsible for the transport of information to and from the brain and the ear. The brain converts these signals into sound. The inner ear is important for maintaining the body balance. The fluid and small cells in the inner ear stimulate the auditory nerve and help in body balance.
-
As a person ages, changes occur in the structures of the ear. As a result, their functions decline. The ability to hear sound is reduced. This is because of the increase in the threshold. There can be issues in maintaining body balance, such as sitting, standing, and walking. The hearing loss due to aging is called presbycusis. It affects the quality of hearing in both ears. The ability to catch high-frequency sounds can decline. People may also find it difficult to distinguish between certain sounds. They can have trouble focusing on a conversation mixed with a lot of background noise. People may also have a ringing or buzzing sound in their ears as they age. This is called tinnitus. Wax buildup, medicines that can cause damage to the structures within the ear, or mild hearing loss can cause tinnitus. The accumulation of ear wax can also cause hearing loss. Clearing the wax can improve hearing.
-
Vision: When the eye processes the light and the brain interprets it, it results in vision. Light passes through the cornea (the transparent part of the eye) and the pupil (the black opening in the middle of the colored part of the eye). The pupil increases in size (dilates) or reduces its size (contricts) depending on the amount of light. The colored part of the eye (called the iris) controls the dilation and constriction of the pupil. The light then reaches the lens, which focuses the light on the retina (the innermost layer of the eye sensitive to light). The retina translates light into a nerve signal, which is carried to the brain through the optic nerve. The brain interprets that signals, and vision is established.
-
As one ages, the structures in the eye also change. The cornea becomes less sensitive to light. Studies show that by the age of sixty, the size of the pupil may reduce to about one-third of the size it had when a person was twenty. It may take time for the pupil to adjust as one moves from bright light to dim light. The lens becomes less flexible and cloudy as one ages. This condition is called cataract. The amount of fat tissue supporting the eye reduces, causing the eye to sink into the socket. People often find it challenging to drive at night due to issues with glare, brightness, and darkness. A gel-like substance called vitreous humor within the eye begins to decrease. This causes the formation of floaters (small dark spots) within the eye. A sudden increase in the number of floaters can be concerning and require professional attention. Peripheral vision (side-vision) also decreases as one ages. This can cause a decrease in activity and interaction with other people. The eye muscles become weak, which makes it difficult to move the eye in different directions. The weakening of eye muscles also causes them to sag.
-
Taste And Smell: The sense of taste is always coupled with smell. The smell of food always enhances its taste. The nerve endings in the lining of the nose initiate the sense of smell. There are about ten thousand taste buds, that help one to know sweet, salty, sour, and bitter. The sense of taste and smell plays an important role in enjoying food and detecting safety. A sumptuous meal can flourish social interactions and happiness. On the other hand, the smell can also help to detect dangers, like leakage of cooking gas, smoke, or even spoilt food. The number of taste buds decreases as one ages. Sensitivity to these five tastes reduces after sixty. In addition, the oral cavity produces less saliva, which causes the mouth to become dry, affecting the way how one perceives taste. In addition, the nerve endings in the lining of the nose reduce as one ages. All these factors reduce one’s interest and enjoyment in eating food.
-
Touch: It is the sense of touch that helps one to know pain, temperature, pressure, vibration, and body position. These are done with the help of nerve endings in the skin, muscles, tendons, joints, and internal organs. With age, the sensation of touch decreases. This could be due to the decrease in the blood flow to the nerve endings, to the spinal cord, or to the brain. The spinal cord transmits the signals and is interpreted by the brain.
Conclusion
A decline in sensory functioning may not affect the quality of life until the age of about seventy-five. Before the age of seventy-five, a decline in sensory functioning could be due to injuries or some disease conditions. As one begins to notice changes in the quality of life, various adaptive measures can be tried to improve life. This can include the use of glasses for vision loss, hearing aids or lip reading for hearing loss, and so on.
