Careblazer, when most people talk about dementia, the focus is usually on memory loss or changes in behavior. While those symptoms are common, dementia also affects something far more basic but just as important. It affects how a person experiences the world through their senses.
Sight, sound, taste, touch, and smell all shift as dementia progresses. These changes can make everyday life confusing, frightening, or overwhelming for the person you love. They can also make caregiving much more difficult if you are not aware of what is happening behind the scenes.
In this guide, I want to help you understand how dementia impacts each of the five senses, how these changes differ from normal aging, and what signs to look for so you can better support your loved one.
My hope is that after reading this, you will feel more prepared, more compassionate, and more confident in responding to sensory changes that might otherwise be misunderstood.
Let us take this one sense at a time.
Understanding Vision Changes in Dementia
Normal Aging vs Dementia Related Vision Changes
As we age, it is normal for our eyes to require more light, slower focusing, or a stronger prescription. Many older adults notice they have a harder time reading fine print or driving at night. These changes are expected and usually improve with glasses, brighter lighting, or simple adjustments.
In dementia, the eyes themselves may work perfectly well. The problem is in the brain. Dementia disrupts how the brain interprets what the eyes are seeing. Even when the information reaches the eye correctly, the brain may be unable to understand it.
How Vision Can Change in Dementia
Here are some of the most common examples of dementia related visual processing problems:
Trouble with spatial awareness
Your loved one may misjudge how far away a chair is and end up sitting beside it or missing it completely. They may walk very cautiously, especially around patterned rugs or shiny floors. Something that looks ordinary to you may look like a hole, a step, or a dangerous surface to them.
Difficulty recognizing faces or objects
This is one of the most painful changes for families. People with dementia sometimes look directly at someone they love and still cannot recognize who they are. This is called facial blindness or prosopagnosia.
It is not personal. It is not a lack of love. It is a change in the way their brain processes visual information.
The same thing can happen with objects. Someone with dementia may look at a fork but not understand what it is or what to do with it. When you see confusion at the dinner table, it may not be memory loss. It may be visual misrecognition.
Visual hallucinations
In Lewy body dementia and Parkinsons disease dementia, visual hallucinations are especially common. A person may see people, animals, or objects that are not present. These experiences are real to them because their brain is generating the image even though their eyes are not.
Posterior cortical atrophy
In this form of dementia, visual processing problems are often the earliest symptom. Someone may have trouble reading, recognizing objects, judging distances, or navigating familiar places long before memory changes appear.
Day to Day Signs You Might See
Your loved one might:
• Step around a rug as if it were a hole
• Avoid shiny floors they believe are wet
• Look confused when handed a familiar object
• Stare at you blankly as if they do not know you
• Swat at things in the air because of hallucinations
These changes often confuse families, but they are all clues that vision processing in the brain is affected.
Hearing Changes in Dementia
Normal Aging vs Dementia Related Hearing Problems
Many older adults experience hearing loss. They ask people to repeat things, turn up the television, or have trouble in noisy places. These are usually issues with the ears themselves and often improve with hearing aids.
With dementia, the ears may work fine. The challenge is the brain’s ability to interpret what it hears.
Your loved one may hear your words but be unable to understand their meaning. They may listen to the sound but cannot process the message.
Common Hearing Related Changes in Dementia
Difficulty understanding speech
Especially in noisy environments, the brain struggles to separate important sounds from background noise. Your loved one might be able to hear the waitress speaking, but their brain cannot process her words.
Sound distortion
Sometimes voices sound too loud, too harsh, or confusing. This is why someone with dementia may accuse you of yelling at them even when you are speaking normally.
Trouble following conversations
They may nod politely while talking to you, but moments later seem confused. The nodding was not understanding. It was an attempt to keep up without revealing their difficulty.
What You Might Notice
• Repeatedly asking what, even though their hearing seems fine
• Turning the television volume up extremely high
• Saying things like stop yelling at me when you are speaking gently
• Avoiding conversations because they feel overwhelmed
To help with this, try reducing background noise, facing your loved one while speaking, and breaking information into shorter, simpler phrases.
Touch and Physical Sensation
How Normal Aging Differs from Dementia
As we age, our skin becomes thinner and more sensitive. We may feel cold more easily or be more aware of aches and pains.
In dementia, touch can become unpredictable. The brain may misinterpret sensory input, causing over sensitivity or under sensitivity.
Common Touch Related Changes in Dementia
Heightened sensitivity
Even a light touch on the arm may feel painful. Water from the shower can feel unbearable. Clothing may feel itchy or irritating even if it never bothered them before.
Reduced sensitivity
Some people may not notice pain, heat, or discomfort. They may hold a hot cup without realizing it is burning them. They may injure themselves scratching because they cannot feel the damage they are causing.
Self stimulation behaviors
Picking at skin, rubbing textures, tapping surfaces, or seeking pressure can all be signs their brain is craving sensory input.
Signs You Might See
• Pulling away from hugs or touch
• Complaints that clothing is uncomfortable
• Picking at skin until it bleeds
• Holding very hot items without noticing
Touch is deeply tied to comfort and safety, and these changes can make bathing, dressing, and personal care challenging.
Changes in Taste and Appetite
Normal Aging vs Taste Changes in Dementia
Taste naturally fades with age. Foods may need more seasoning. Appetite may change.
In dementia, the loss of taste is more pronounced because the brain is not processing flavor the same way.
Why So Many People With Dementia Crave Sugar
Sweet taste buds are the last to fade. Even when other flavors become muted, sweetness still registers strongly. This is why someone who never liked sweets before may suddenly crave desserts or sprinkle sugar on foods that do not need it.
Other Taste Related Changes
Inability to detect spoiled food
They may eat food past its expiration date because they cannot taste that it has gone bad.
Sudden aversions to foods they used to enjoy
Meats, vegetables, and proteins may taste bland or unpleasant while sweets remain appealing.
Requests for strange combinations
Their brain may be seeking strong flavor stimulation.
Signs You Might See
• Pouring sugar repeatedly into cereal or tea
• Saying food tastes wrong or funny
• Refusing meals but asking for dessert
• Eating spoiled food without realizing it
There are safe ways to enhance flavor without adding too much sugar, such as cinnamon, nutmeg, citrus, or mild sweetness added to healthy foods.
Changes in Smell and Safety Risks
Why Smell Loss Matters in Dementia
Smell loss is one of the earliest symptoms of Alzheimer’s disease. This is because the olfactory bulb, the part of the brain involved in smell, is one of the first regions affected.
Unlike normal aging where smell slowly fades, dementia can cause a more sudden or dramatic decline.
Common Smell Related Challenges
Not noticing spoiled food
Your loved one may eat food that has gone bad because they cannot smell the sour odor.
Not detecting smoke or gas leaks
This is a serious safety concern. If they no longer smell danger, they cannot respond to it.
Using excessive perfume or cologne
Because they cannot smell themselves, they may over apply fragrance.
Signs You Might Notice
• Eating expired food
• Not noticing strong odors that others comment on
• Failing to recognize smoke, burning food, or gas leaks
• Wearing too much perfume or cologne
For safety, consider installing gas detectors, smoke alarms, and checking food regularly.
Bringing It All Together
When dementia affects the senses, it can change how a person perceives the world in ways that are invisible from the outside.
The person you love may hesitate, act confused, become frightened, or respond in ways that seem unpredictable. These reactions are often driven by sensory changes, not stubbornness or intentional behavior.
Understanding these changes helps you respond with patience and compassion. It gives you a clearer picture of why certain behaviors happen and how you can support your loved one more effectively.
If you have noticed any changes in your loved one’s senses, you are not alone. These challenges are common and often misunderstood. With the right knowledge and support, you can make their daily life easier and safer.
If You Want More Support
If you would like ongoing help, encouragement, and weekly guidance, I invite you to join the Dementia Dose newsletter. It is the best way to stay connected, learn new strategies, and get support from someone who understands the emotional and practical challenges of caregiving. You can sign up here!
You are doing incredible work, Careblazer. I am sending you so much love.
Read More:
Posterior cortical atrophy https://pubmed.ncbi.nlm.nih.gov/22265212/
Changes in appetite, food preference, and eating habits in frontotemporal dementia and Alzheimer’s disease: https://pubmed.ncbi.nlm.nih.gov/12235302/
Reward deficits in behavioural variant frontotemporal dementia include insensitivity to negative stimuli https://pubmed.ncbi.nlm.nih.gov/29053832/
Aging-associated sensory decline and Alzheimer’s disease https://link.springer.com/article/10.1186/s13024-024-00776-y
The combined effects of visual impairment, hearing loss, and olfactory dysfunction on cognitive impairment
https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/alz.70439?utm_source=chatgpt.com
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