When a loved one is diagnosed with dementia, one of the first questions loved ones ask is, “What’s actually happening inside their brain?” Understanding what changes occur and how those changes affect thinking, behavior, and movement can help you respond with more empathy and confidence.
Dementia isn’t one single disease. It’s a group of conditions that damage the brain’s nerve cells and disrupt how different regions communicate.
Depending on which areas are affected, people may experience memory loss, personality changes, or even differences in how they move.
Scientists have made great strides in understanding how dementia develops, from the buildup of proteins that damage neurons to the way those brain changes appear in daily life.
Still, every person’s experience is unique. The progression, symptoms, and emotional impact can differ dramatically, even between two people with a similar diagnosis.
In this article, we’ll look at how dementia affects the brain and what that means for behavior and physical function. We’ll then touch on testing for dementia and the importance of early detection.
How Does Dementia Change the Brain?
Dementia begins in the brain, where nerve cells start to break down. These cells lose their ability to communicate with each other, which disrupts how different regions of the brain work together.
Over time, the damage spreads and affects memory, judgment, movement, and emotions.
Each type of dementia targets specific areas of the brain.
- Alzheimer’s disease often starts in the hippocampus, which controls memory and learning.
- Frontotemporal dementia affects the frontal and temporal lobes, which shape language, decision-making, and behavior.
- Lewy body dementia involves protein deposits that interfere with movement and alertness.
- Vascular dementia occurs when blood flow to the brain is reduced, depriving neurons of oxygen and nutrients.
No two people experience dementia in the same way. The pattern and pace of progression depend on genetics, overall health, and other factors. One person may first notice memory problems, while another may experience mood changes or slowed movement.
Neuroscientist Dr. Barbara K. Lipska offered a vivid glimpse of what this loss of brain function can feel like from the inside. In 2015, after melanoma spread to her brain, tumors and inflammation disrupted networks involved in judgment, self-monitoring, and insight. This created symptoms that looked, to others, like severe cognitive and personality change.
Yet from her perspective, she felt essentially unchanged. Looking back, she described the experience plainly:
“I thought they went mad, or they changed, not me… I had absolutely no insight […] I felt I understood for the first time what many of the patients I study go through — the fear and confusion of living in a world that doesn’t make sense; a world in which the past is forgotten, and the future is utterly unpredictable.“
In other words, the very systems that would normally alert a person that something is wrong were the ones being impaired.
Her story helps explain why some people with dementia can seem unaware of their condition or confused by others’ reactions. If the brain’s “self-checking” circuitry is compromised, the person may genuinely conclude that the problem lies outside of them.
It is important for us to understand this dynamic as caregivers. When you see unusual behaviors or communication difficulties, it helps to remember that these are symptoms of the disease, not choices your loved one is making.
The lesson here is that correction or criticism won’t get you anywhere. You must have empathy and patience, because your loved one, ultimately, is scared by the confusing state of the world around them.
What Behavioral and Emotional Changes Should You Expect?
Behavioral and emotional changes are often the most visible signs of dementia.
You may notice mood swings, anxiety, or irritability. Some people repeat questions, withdraw from conversations, or express anger when they feel overwhelmed.
Others experience laughter or sadness that seems unrelated to what is happening around them. These reactions are not deliberate. They are a response to the brain’s struggle to process and interpret the world.
Common Brain-Behavior Connections
| Affected Brain Region | Typical Changes in Behavior or Emotion | How Caregivers Can Help |
| Frontal lobe (controls judgment, decision-making, social behavior) | Impulsivity, disinhibition, inappropriate comments, lack of empathy | Set clear boundaries, redirect conversations gently, maintain calm tone |
| Temporal lobe (language and understanding) | Difficulty finding words, repeating phrases, frustration during conversation | Use short, simple sentences, avoid correcting, encourage expression through gestures |
| Amygdala and limbic system (emotional regulation) | Heightened anxiety, fear, mood swings, anger outbursts | Offer reassurance, reduce sensory distractions, validate emotions |
| Hippocampus (memory and orientation) | Confusion about time or place, misplacing items, accusations of theft | Keep routines consistent, label items, avoid confrontation |
| Parietal lobe (spatial awareness and movement) | Clumsiness, trouble navigating familiar spaces, pacing | Ensure clear pathways, use contrasting colors, provide gentle guidance |
These behavioral changes reflect the parts of the brain that are struggling to function normally. As we’ve mentioned, understanding the connection between physical brain changes and visible actions helps you respond with empathy rather than frustration.
Practical Ways to Respond
- Speak slowly and clearly, allowing time for responses.
- Maintain eye contact and use a calm, friendly tone.
- Simplify choices and avoid open-ended questions.
- Redirect distress with a familiar song, photo, or brief walk.
- Focus on comfort and connection, not correction.
When you approach these moments with patience and understanding instead of giving voice to frustration, you reduce tension for both yourself and your loved one. You also strengthen trust, which is essential to their sense of safety and well-being.
At Bridges®, we often reflect on a quote from Maya Angelou that captures the essence of dementia care:
I’ve learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel.”
– Maya Angelou
This message is especially powerful in memory care. A person living with dementia may not recall your name or the conversation you shared, but they will remember how you made them feel. They will light up for someone who treats them with kindness while withdrawing from someone who shows anger or impatience.
Keep this in mind as you care for your loved one.
How Does Dementia Affect Physical Abilities and Movement?
We often associate dementia with memory and thinking problems, but its effects on movement and coordination are just as important to understand.
Remember that the brain controls every physical action, from walking to swallowing. So, as dementia progresses, the regions responsible for motor skills and balance begin to change.
These changes can appear subtle at first. A person may move more slowly, seem less steady, or pause before taking a step. Over time, these small signs can develop into difficulty walking, standing, or performing daily activities safely.
Why Do Physical Changes Happen with Dementia?
The brain’s motor cortex, cerebellum, and basal ganglia play key roles in coordination and control. As dementia affects these areas, communication between the brain and body weakens. Muscles may remain strong, but the brain struggles to send and interpret movement signals.
In other words, it is not an aging body that is causing the issue, but the disease damaging the brain’s ability to process important signals.
This process is sometimes referred to as Parkinsonism, a collection of symptoms such as stiffness, shuffling, or slowed movements that can resemble Parkinson’s disease.
These symptoms are not caused by Parkinson’s itself but by how dementia disrupts similar brain pathways.
| Physical Change | Why It Happens | How Caregivers Can Support |
| Unsteady gait | Brain’s motor centers lose coordination | Encourage slow, deliberate walking and keep floors clear of obstacles |
| Slowness of movement | Brain delays signals between thought and motion | Allow extra time for movement, avoid rushing, offer a hand for balance |
| Poor balance or frequent falls | Spatial awareness and reflexes decline | Install grab bars, remove loose rugs, and consider physical therapy |
| Difficulty initiating movement (apraxia) | Brain struggles to start sequences like standing or turning | Provide gentle cues, such as touch or verbal guidance, to prompt movement |
| Stiffness or rigidity | Muscles respond slowly to brain commands | Encourage light stretching, gentle exercise, and regular position changes |
It’s important for caregivers to understand that even small changes in mobility and balance can affect safety. Paying attention to early signs will help prevent falls and injuries. Offering some help when it’s needed can also help with the individual’s confidence.
Learn more about the correlation between dementia and balance.
Promoting Confidence and Safety
- Keep pathways open and well-lit.
- Use contrasting colors for steps or transitions to help with depth perception.
- Provide sturdy, comfortable footwear.
- Offer consistent physical activity, such as short walks or seated exercises.
- Get professional guidance from an occupational or physical therapist to maintain mobility.
It’s not always easy to encourage movement when your loved one feels tired or unsteady, but even gentle activity can help them feel stronger and more in control.
This is why the effort is worthwhile.
Every walk down the hallway or stretch at the table is a win. These actions build confidence and remind a loved one that they can still participate in life with your help and encouragement.
What Are Some of the Most Concerning Behaviors, and How Can You Manage Them?
Certain dementia-related behaviors can be especially distressing. Four of the most challenging are wandering, sundowning, aggression, and resistance to personal care. These are worrying because they place you and your loved one at risk and can damage relationships.
Understanding what drives these behaviors helps you prevent them when possible.
Let’s examine each:
Challenging Behaviors
Wandering
Wandering is one of the most concerning behaviors because it can lead to falls, injuries, or a loved one getting lost. It often happens when someone feels restless, confused about their surroundings, or believes they need to return to somewhere familiar, like a former workplace or home.
How to respond to wandering:
– Keep your loved one’s environment safe without restricting them. Install motion sensors to alert you if they leave a ‘safe’ area.
– Offer structured daily activities to ease restlessness and ‘burn off’ energy.
– Redirect with reassurance and validation. “Let’s take a walk together” works much better than shutting them down with a “You can’t go outside”.
– Make sure your loved one wears an identification bracelet or carries contact information on them.
– Notify neighbors and the local police.
Remember that wandering usually points to an unmet need for movement or purpose. Meeting the underlying need is often the best way to reduce the behavior.
Sundowning
Sundowning refers to the late-day confusion or agitation that begins in the afternoon or evening (coinciding with the sun going down and the light dimming). Sundowning happens because dementia affects the body’s internal clock, disrupting sleep cycles and energy patterns.
How to respond to sundowning
-Keep daily routines predictable, especially around mealtime and bedtime.
-Reduce stimulation by lowering noise and dimming lights when it’s time to relax.
-Close blinds before dark and turn on warm lighting to reduce confusion about the time of day (especially in the winter when it gets dark early)
-Avoid caffeine or long naps late in the day.
-Offer soothing activities such as soft music, gentle conversation, or light hand massage.
Again, sundowning is often a time of agitation for an individual experiencing memory loss. Your best bet is to be a calming presence. Use a reassuring tone and don’t give in to any attempt to correct or explain.
Aggression or Anger
Aggression may appear suddenly and can be verbal or physical. It often stems from fear, frustration, or sensory overload. When communication becomes difficult, a loved one may lash out to express distress.
How to respond to anger or aggression
-Try to step back and stay calm. Giving some space is a better idea than arguing or chastising (if it is safe to give them space).
-Validate their emotions, showing you understand their anger or frustration
-Check for basics like hunger, pain, or fatigue. In other words, are they trying to communicate a basic need?
-Reintroduce something comforting once they have calmed a bit.
With aggression, especially from a loved one, it is especially important to remember that it is a symptom of the disease, a glitch in how the brain is reacting to confusion and discomfort.
Resistance to Personal Care
As caregivers, we always want to ensure our loved ones are taken care of. However, refusing to bathe, change clothes, or brush teeth is common. Dementia can alter perceptions, making water feel too cold or hot or things like mirrors appear frightening. Even just the touch and textures of clothing can feel unpleasant.
How to respond to resistance
-Keep the environment warm, bright, and private.
-Use calm, positive language: “Let’s freshen up before dinner,” instead of “You need a bath.”
-Offer choices to preserve dignity: “Would you like to wash your face or hands first?”
-Break tasks into smaller steps. Praise cooperation and stop if frustration builds.
Comfort and respect matter more than completing the full task. A calm caregiver helps the person feel secure and willing to try again later. Learn more about resistance and refusals.
Summary of Behaviors and Responses
| Behavior | Possible Cause | Helpful Response |
| Wandering | Restlessness, confusion, searching for familiarity | Provide structure, safe spaces, and gentle redirection |
| Sundowning | Disrupted sleep-wake cycle, fatigue | Maintain routine, reduce stimulation, and use soft lighting |
| Aggression | Fear, frustration, pain | Stay calm, validate emotions, and redirect once calm |
| Resisting personal care | Fear, embarrassment, confusion | Offer choice, comfort, and privacy; avoid confrontation |
Why Does Early Detection Matter?
There is currently no cure for Alzheimer’s Disease and other dementias. However, new medications and lifestyle interventions are most effective when started early, and can make a difference in the progression of the disease and alleviation of some symptoms.
Early detection also gives families time to:
- Create a care plan together
- Explore supportive programs such as memory care
- Make home or financial adjustments before a crisis
- Look for local resources
Early knowledge also reduces fear. Understanding what is happening allows families to prepare rather than react. Many families report, counterintuitively, that it is sometimes a relief to ‘put a name to it’.
Below is an interview with Camille Ciarametaro, Senior Advisor at Bridges Lexington. In it, she speaks from experience about the benefits of an early diagnosis.
How Can Early Screening Tools Help Detect Dementia?
When memory changes begin to appear, families often wonder what is normal aging and what might be something more serious. Early screening tools can help you start that conversation with a doctor and make informed choices sooner.
The Self-Administered Gerocognitive Examination (SAGE test) is one of the most recognized tools for this purpose. Developed at Ohio State University, it is a brief, pen-and-paper test that takes about ten to fifteen minutes to complete.
The test measures thinking skills such as:
- Memory and recall
- Problem-solving and judgment
- Orientation to time and date
- Language use and reasoning
- Three-dimensional construction and spatial awareness
The test asks participants to list items (for example, twelve animals), draw a clock showing a specific time, identify today’s date, and explain how two objects are similar.
Missing six or more questions may suggest the need for further evaluation by a healthcare professional.
What Are the Limitations of the SAGE Test?
SAGE is only a screening tool. It’s not a diagnosis. As such, it is a mere first step. A high or low score does not confirm or rule out dementia.
Things like stress, depression, poor sleep, or medication side effects can affect performance on the SAGE test.
Key reminder: Only a physician can diagnose Alzheimer’s or other dementias.
They will use a combination of:
- Detailed medical and cognitive history
- Neurological exam
- Brain imaging, such as MRI or PET scans
- Blood tests for Alzheimer’s biomarkers
So, SAGE is nothing more than a starting point. The most you could take from it would be that a further, more comprehensive assessment might be helpful.
Still, it is worth doing. If you or a loved one notices increased forgetfulness, repetition, or difficulty following conversations, consider taking the SAGE test and sharing the results with a doctor.
It’s a great idea to keep a simple journal of observations to give the physician additional context.
Early action opens doors to more treatment options and better planning.
What Are Some Other Screening Options?
Here are three other brief tests that a clinician could administer to evaluate cognitive changes:
| Test | Best for | Approx Time |
| MoCA (Montreal Cognitive Assessment) | Detecting mild cognitive impairment | 10-15 mins |
| MMSE (Mini-Mental State Examination) | Tracking moderate to severe decline | 5-10 mins |
| Mini-Cog | Fast primary-care screening | 3-5 mins |
Where Can You Turn for Support?
Caring for someone with dementia begins with understanding how the brain changes and how those changes affect memory, movement, and behavior. We find that the more you know, the easier it becomes to respond in a way that supports your loved one.
At Bridges® by EPOCH, this understanding guides everything we do. Our purposeful design and wellness-focused lifestyle create safe, comfortable environments where people living with memory loss can continue to live with dignity. Our teams receive specialized training to interpret behaviors with care. Read more about our approach to memory care.
We also provide support for loved ones. Through free caregiver support groups and educational events, we help caregivers gain knowledge, share experiences, and build a community of understanding.
To learn more, visit our communities, contact us, or visit our resource center, with insights, podcasts, and more.
