Aging Changes The Senses

Senses receive information from the environment around you which can be in the form of light, sound, smells, taste, and touch; this sensory information is converted into nerve signals that are carried to the brain where the signals are turned into meaningful sensations.

A level of stimulation is required before you become aware of sensory sensation, the minimum level is called sensation threshold, aging raises this threshold as a result you need more stimulation to become aware of the sensation.

Aging processes unfortunately can affect all of the senses, typically hearing and vision are affected the most and can require glasses, hearing aids, or lifestyle changes to improve ability to hear.

The ears are responsible for hearing and maintaining balance. Hearing happens after sound crosses the eardrum to the inner ear, vibrations are changed into nerve signals in the inner ear and are carried to the brain by the auditory nerve. Balance/equilibrium is controlled in the inner ear by fluid and small hair in the inner ear that stimulate the auditory nerve to help the brain maintain balance.

With age structures inside the ear start to change and functions decline, ability to pick up sounds decline, and you may have problems with balance as you stand, walk, stand, and sit. Presbycusis is age related hearing loss and typically affects both ears, often affecting the ability to hear high frequencies, telling the difference between sounds, hearing conversations when there is background noise, and having discussions with health care providers. Additionally impacted ear wax can cause hearing issues and is a common problem with age.

Vision occurs when light is processed by the eyes and is interpreted by the brain: light passes through the cornea continuing through the pupil which becomes larger or smaller to control the amount of light entering the eye; iris’ controls pupil size, after light passes through the pupil it reaches the lens which focus light on the retina that convert light energy into a nerve signal the optic nerve carries to the brain to be interpreted.

Changing eye structures make the cornea become less sensitive, and you may not notice eye Injury. By the age of 60 the pupils may decrease to be one third of the size; pupils may react more slowly in responses to light/dark; lenses becomes yellowed, less flexible, and slightly cloudy; fat pads supporting the issue decrease and the eyes sink into their sockets. Glare, brightness, and darkness may make it hard to drive a night, and it becomes harder to tell blues from greens. Vitreous inside of the eyes shrink and cause floaters in the field of vision, typically it does not reduce vision. Reduced peripheral vision is common and can limit ability to interact with others and driving becomes dangerous. Weakened eye muscles may make it hard to move eyes in all directions and are less able to fully rotate eyes, and the aging eye may not produce enough tears leading to dry eyes.

The sense of taste and smell work together, most tastes are linked to odors: Smell begins at the nerve endings in nose lining; and there are about 10,000 taste buds for detecting flavors. Taste and smell play roles in food safety and enjoyment. Taste buds numbers decrease with age, each time a taste bud shrinks sensitivity to the 5 tastes declines after the age of 60, and the mouth produces less saliva causing dry mouth which also affects sense of taste. After 70 sense of smell can diminish, which may be related to loss of nerve endings and less mucus production in the nose that helps odors stay in the nose to be detected by nerve endings, and helps clear odors from the nerve endings as well. Diseases, smoking, certain medications, and exposure to harmful particles in the air can speed up loss of these senses, which can lessen interest in eating, and ability to sense certain dangers such as bad foods, smoke from fire, or a natural gas leak.

Sense of touch is also very important, this makes you aware of pain, pressure, vibration, pressure, and temperature. Muscles, tendons, joints, skin, and internal organs have receptors/nerve endings to direct these sensations, some provide the brain basic information about the position and condition of internal things. The spinal cord transmits nerve signals and the brain interprets these signals; the amount and type of touch sensation is interpreted as being either pleasant, unpleasant, or neutral.

With age touch sensations can be changed and/or reduced which can occur due to decreases of blood flow to the receptors, spinal cord, or brain. Health problems, certain medications, and bad nutrition can also cause sensation changes, as well as brain surgery, brain problems, confusion, nerve damage, injury, and chronic disease. Symptoms of changed sensory can vary based on cause such as deceased temperature sensitivity making it hard to tell the difference from hot to cold increasing risks of injury from burns and hypothermia.

As ability to detect vibration, touch, and pressure declines risk of injuries such as pressure ulcers and fractures increase. After reaching 50 there may be a reduced sensitivity to pain, or ability to feel and recognize pain but it doesn’t bother you, as a result you may not know how severe an injury is and not seek help when it is needed. Additionally with age the skin becomes thinner which can make older populations more sensitive to light touches.  Perception of vibration through touch can decrease with age even with sustained visual attention.

Reduced ability to perceive the body as it is in relation to the floor can lead to problems with mobility and walking which increases the risks of falls and is a common issue for older populations, additionally is a serious concern for fractures.

Should you notice a change in touch, pain, or have problems talking, walking, or standing talk to your healthcare provider who can help you to manage the symptoms. At home there are measures which you can take which may help you to stay safe such as: lowering the water heater temperature to no higher than 120F/49C to avoid burns; checking the thermometer to decide you to dress rather than waiting to feel hot/cold, and using a programmed thermostat to control inside temperature; regularly inspect skin including the feet/toes for injuries, should one be found do not assume it is not serious because the area is not painful get it looked at.

“Health care professionals can measure sense of touch via vibrotactile sensitivity and a dozen other functional biomarkers of Aging with devices such as the Agemeter. An estimated function age is provided after the tests are completed as well as a percentile ranking for each test result. Determining how young or old a person functions is the way to validate the results of biochemical and genetic biological age tests and whether aging intervention therapies are working.” ~ Elliott Small, President and Founder of Centers For Age Control Inc.