It starts with a misplaced set of keys. Then, maybe a missed appointment or a name that stays stubbornly on the tip of the tongue. Most of us see these things and immediately jump to one conclusion: memory. We’ve been conditioned to think that dementia is just a fancy word for forgetting where you parked your car. But honestly? That’s barely the tip of the iceberg.
Dementia isn't a single disease. It’s an umbrella term—sorta like "heart disease"—covering everything from Alzheimer’s to Lewy Body and Vascular dementia. Because it affects the actual physical wiring of the brain, the common behaviors of dementia are often way more bizarre, frustrating, and heartbreaking than just a simple "senior moment."
If you’re caring for someone or just worried about a family member, you've probably noticed that the personality shifts are what actually keep you up at night. The brain is literally shrinking in specific areas. When the frontal lobe takes a hit, social filters vanish. When the parietal lobe struggles, a hallway looks like a bottomless pit. It’s not "bad behavior." It’s a hardware failure.
The "Personality Flip" and Why It Happens
One of the most jarring common behaviors of dementia is when a lifelong "sweetheart" suddenly starts swearing like a sailor or accusing family members of stealing. It’s gut-wrenching. You’ve known this person for thirty years, and suddenly they’re a stranger.
Dr. G. Allen Power, a renowned geriatrician and author of Dementia Beyond Drugs, often points out that these actions are usually attempts to communicate a need that the person can no longer verbalize. If a man with Alzheimer's is trying to take his pants off in the middle of a grocery store, he isn't being "inappropriate" on purpose. He might just have a urinary tract infection (UTI) that feels like fire, or maybe the fabric is itchy and his brain can no longer process how to say, "I’m uncomfortable."
Paranoia is another big one. If someone can’t remember where they put their wallet, their brain fills in the gaps to make sense of a confusing world. "I didn't lose it; someone must have stolen it." It’s a defense mechanism. It’s much less scary to believe in a thief than to admit your own mind is betraying you.
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The Sundowning Phenomenon
Ever noticed how everything gets ten times worse at 5:00 PM? There’s a name for that: Sundowning. As the sun goes down and shadows stretch across the room, the brain’s ability to process visual information tanks.
- A dark rug can look like a hole in the floor.
- Reflections in a window can look like an intruder.
- Fatigue makes the already-thin patience of a person with dementia snap.
It’s basically a perfect storm of exhaustion and sensory overload. You might see pacing, rocking, or an intense desire to "go home," even if they are already sitting in their own living room. When they say they want to go home, they usually aren't talking about a physical building. They’re looking for a feeling of safety and familiarity that they can’t find anymore.
Communication Breakdown: Beyond Forgetting Names
We often focus on the words people lose. But the common behaviors of dementia involve a massive shift in how people receive information, too.
Aphasia is the medical term for it. Sometimes they can’t find the word "water," so they call it "the wet stuff." Other times, they can hear you perfectly fine, but your words sound like a foreign language. This is why "word salad" happens—where sentences come out as a jumbled mess of unrelated nouns and verbs.
Specific behaviors to watch for:
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- Repetitive questioning: Asking the same thing 20 times in ten minutes. Their short-term memory is like a chalkboard that gets erased every 30 seconds. They aren't trying to annoy you; they genuinely don't remember asking.
- Loss of initiation: They just sit there. You have to tell them to eat, tell them to get up, tell them to wash. The "engine" of the brain that starts tasks has stalled.
- Shadowing: Following the caregiver everywhere. Like, everywhere. If you go to the bathroom, they’re right outside the door. You are their only anchor in a world that feels like a hallucination. It’s exhausting for you, but for them, it’s survival.
The Sensory World is Breaking
Imagine if your skin suddenly felt like it was crawling with ants, or if the sound of a dishwasher sounded like a jet engine. That’s the reality for many. In Lewy Body dementia, visual hallucinations are a hallmark. People see small animals or children that aren't there.
The Mayo Clinic notes that these hallucinations are often very detailed. A person might see a tiger in the corner of the room. Telling them "it’s not real" rarely helps because, to their firing neurons, it is 100% real.
There's also something called "the 12-inch vision." As dementia progresses, peripheral vision narrows. It’s like wearing scuba goggles. If you approach someone from the side without warning, you’re going to startle them, which can lead to hitting or screaming—behaviors often labeled as "aggressive" when they’re actually just a "fright-flight" response.
Why Do They Hide Things?
Hoarding or "rummaging" is incredibly common. You’ll find spoons in the laundry hamper or piles of junk mail hidden under a mattress.
This usually stems from a deep-seated need to feel productive or to protect belongings. In the mid-to-late stages, the instinct to "gather" takes over. It’s an ancient human drive. If they spent 40 years as an accountant, they might obsessively "file" napkins. If they were a homemaker, they might constantly fold and unfold the same three towels.
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Honestly, the best way to handle this isn't to stop it. It’s to give them a "rummage drawer." Fill a kitchen drawer with safe, tactile objects they can sort through. It gives the hands something to do and calms the nervous system.
The Myth of the "Dementia Choice"
The hardest part for families is accepting that the person isn't "doing this on purpose."
When your mom calls you a "hired stranger" or refuses to bathe, it feels personal. It feels like a power struggle. But the brain’s executive function—the part that handles logic, consequences, and sequencing—is literally dying. They can’t "try harder." You wouldn't ask a person in a wheelchair to "try harder" to walk; we have to view these common behaviors of dementia through that same lens of physical disability.
Actionable Steps for Managing Daily Life
If you’re dealing with these behaviors right now, stop trying to win arguments. You will lose 100% of the time. Instead, pivot your strategy toward the following:
- The "Agree and Redirect" Rule: If they say they need to go pick up their kids from school (and their kids are 50 years old), don't argue. Say, "The bus is running late today, let's have some tea while we wait." You validate their reality and then move them toward a different activity.
- Simplify the Environment: Remove "busy" patterns from rugs and wallpaper. Clear the clutter. Use high-contrast plates (like red plates for white mashed potatoes) so they can actually see their food.
- Check for Physical Triggers: Agitation is often just a mask for pain, hunger, or a full bladder. Before reaching for antipsychotic meds, check if they’re constipated or have a toothache.
- Limit Choice: Don't ask, "What do you want for lunch?" That’s too much processing. Ask, "Do you want soup or a sandwich?" Or better yet, just put the sandwich down.
- Get a Medical Baseline: If a behavior changes overnight—literally within 24 hours—it’s probably not the dementia progressing. It’s likely a UTI or a medication side effect. Get a urinalysis immediately.
The goal isn't to fix the person. You can't. The goal is to modify the environment and your own reactions to minimize distress. It’s a shift from "correcting" to "connecting." Focus on the emotion behind the words, not the words themselves. If they’re angry, they’re probably scared. Address the fear, and the anger usually follows it out the door.
Next Steps for Caregivers: Start a "behavior log" for three days. Note the time of day, what happened right before a breakdown, and what the lighting/noise level was like. You’ll likely see a pattern—maybe the neighbor’s leaf blower or the midday sun is the real culprit. Once you identify the trigger, you can change the environment before the behavior even starts. Check the Alzheimer's Association for local support groups; doing this alone is a recipe for burnout.