Sensory Changes with Alzheimer’s disease and Dementia

Often as the Alzheimer disease progresses interpretation of sensory input or processing of sensory input is also impaired so the person does not perceive information from his or her environment accurately.  This impairment in sensory feedback often affects the way the Alzheimer’s client reacts to a situation or approaches a task.   Knowing some of the changes that they experience will help you better adapt their environment and increase their ability to participate in daily activities and to reduce their stress level. 

Increase Sensitivity to Hot and/or Cold

Often they will say their food is too hot or that they are cold.   I will cool my mother’s food in the refrigerator or a few minutes before we sit down and eat together.   If the food is hot she will often stop eating.   Slightly above room temperature seems warm enough.   I also will place yogurt in the microwave for 30-40 seconds to take off the chill and this seems to help her finish it. 

React with fright or flight if touched lightly especially if out of his/her visual field

 It is very important to announce or request before touching someone.   Coming up from behind a person or grabbing them can be very upsetting.   Light touch is an alerting sense.  I will often say something like “Is it OK if I help you with your collar?”  This is less alarming them coming behind her and touching her in the back of her neck.

Tunnel Vision

 Often times an individual with Alzheimer’s disease has less ability to use their peripheral vision.  This is important when approaching a person with Alzheimer’s disease.  Don’t approach from the side instead always come in front of the person. Also when presenting things such as food, medication, clothing, etc. always place the items in the person midline. 

Visual Field also Lowers

 Along with the Tunnel vision the visual field of person with Alzheimer’s disease also becomes progressively lower.   It goes to approximately 30 – 35 inches off the floor.   This is also important if you are using signage for the bathroom or bedroom or if you want to show this person something or if watching television. 

Depth Perception

 Combined with the lower visual fields and the Tunnel Vision, the Alzheimer’s client also has difficulty with his/her perception of depth.   This is seen when the person moves from one surface on the floor to another.   My mother will slow down or stop in a store if she moves from carpet to a tile floor.  This is more evident when the surface she is moving to is dark.   She also has difficulty with steps and does not like to walk on uneven surfaces.   Removing throw rugs is important and providing hand rails along steps for safety and to reduce anxiety related to this problem.  Just being aware that this is happening can help you understand and anticipate this problem. 

Sundowning

 Changes in light and shadows can cause a behavior called “Sundowning”.  Typically Alzheimer’s clients with show increased confusion and some resistive behaviors when the sun goes down.   It was thought that the sun going down created a darker and more shadowed appearance to the world.  This along with the other visual problems can be confusing.   It is suggested that the environment that the client with Alzheimer’s disease is in should always be well light.   The best light is natural light.   Opening curtains during the day and using lights to decrease shadows may help.   New light bulbs, such as Reveal®, are being made to produce a more natural or full spectrum of light which may help with the sun downing behaviors. 

Taste Decreases

Frequently in the elderly due to aging, medication and other health issues, the person loses his/her ability to taste foods.  Sweet and Bitter taste are the last to decrease.   Often times Alzheimer’s clients crave sweets and will avoid other foods.   Try adding some Splenda® to their food to increase the sweetness without the calories or sugar. 

Touch can be used to calm

 A gentle and firm touch can be very comforting to the Alzheimer’s client.  You can use this gentle touch or a hug to engage the person in conversation or an active.  Touch can be calming as well.   Try giving the Alzheimer’s client a hand massage with some sweet smelling hand cream. 

Sense of Smell can be calming and used to elicit memories

 Scents like lavender, cinnamon and vanilla can be calming.   Also smells from the past can stimulate memories.   Try baking together.  I often bake with my mother and let her stir the ingredients together.   She seems to enjoy helping and the smell in the kitchen often stimulates memories of her youth. 

Vestibular Sense or the Sense of Movement

 Alzheimer’s clients who are mobile will often pace in the house.  If you take the pacing a sign that the individual needs to move then this would be a perfect time to take a walk.   Going for short walks will help the individual with Alzheimer’s disease maintain their ability to walk safely longer as well as reduce the need to pace and possibility wander?   Movement such as walking also reduces the stress level for both the care receiver and caregiver.  Sometime movement also stimulates verbalization or speech.  Walking can also be calming.

Hearing Problems

Hearing impairment can co exist with Alzheimer’s disease.   If there is no hearing problem the difficulty with processing auditory information exists.   Things that may help are to reduce background noises.   While talking or giving directions turn off the TV, radio, fan, dishwasher, etc.   Be aware of environmental sounds like traffic, heaters, appliances, other individual talking in the area can also effect the Alzheimer’s client’s ability to comprehend or listen.   Remember short sentences with visual or physical cues such as pointing or tapping the object can help the person understand what is being said.