How an Alzheimer's Expert Monitors Herself for Symptoms and the 'Most Important' Clue

Anyone who’s lost a loved one to Alzheimer's disease may be worried about noticing symptoms in themselves.

Alzheimer's takes a terrible toll. It’s the most common cause of dementia — abnormal brain changes that lead to memory loss, impaired thinking skills and confusion.

Patients become unable to learn, remember and recognize family.

The biggest risk factor is age, followed by family history, says Mary Sano, Ph.D., professor of psychiatry and director of the Alzheimer's Disease Research Center at the Icahn School of Medicine at Mount Sinai in New York.

She’s a neuropsychologist — a specialist who focuses on the brain and behavior. A patient may be referred to a neuropsychologist for an evaluation when they, their family or their doctors notice a change in behavior that could signal dementia.

People with cognitive decline may be unaware of the disease in themselves, a condition known as anosognosia. But they may notice important clues in early stages of brain changes.

“I think everyone as they age is probably attentive to cognitive impairment,” Sano tells TODAY.com.

“A very common thing can be that people really do feel a difference that others aren't aware of or don't acknowledge. I see that very often in participants. They say, ‘I'm just not doing this as well,’ or, ‘I feel foggy when I'm trying to do something.’”

Knowing what she knows, here are the Alzheimer’s disease symptoms she pays attention to in her own life:

Missing Periods of Time

Not being able to figure out: What did I do for breakfast this morning? What routine did I follow this morning?

“That can be a problem,” Sano notes.

Staci Marklin, a 47-year-old Tennessee woman diagnosed with early-onset Alzheimer's disease, says she was “having instances where it felt like things were just gone,” including when her 3-year-old son was born.

“Once someone asked me my son's date of birth, and I had no idea,” Marklin told Buzzfeed.

Hearing Concern from Others

The "most important thing" is being open to hearing a concern from others, since Alzheimer’s disease symptoms are often identified by someone else, Sano says.

“Be open to the fact that someone says, ‘I don't think you're doing this as well as you used to,’” she advises.

Accept it as someone noticing a change that's worthy of getting checked out, she adds.

For example, other people commenting that you’re repeating yourself or asking the same question over and over again might be cause for concern.

Misplacing Things in Odd Places

There are common stories of someone putting their keys in the refrigerator or another inappropriate place, Sano notes.

“My experience is when those things are happening, many more things have happened before that,” she says.

Being More Anxious or Upset

Not being able to find your keys or your phone provokes unusual anxiety.

“Sometimes people can have an awareness of that, and are particularly irritable or anxious around their own performance,” Sano says.

“That might indicate that, in fact, they have this worry about some change that they can't articulate, and it's worthy of conversation with a physician.”

Forgetting to Pay Bills

“That can be a very important sign,” Sano says. “I think that's probably the biggest kind of problem.”

How to Get Help

If you’re worried, talk with a friend, family member or another trusted person in your circle and ask if they’ve also noticed changes.

If any of your symptoms are acknowledged by someone else, it’s worthy of a medical evaluation, Sano advises. Tell your doctor about your concerns.

You can be referred to a neuropsychologist for standardized cognitive testing and more.

“If I have someone whose testing is normal, but they really insist that there's something different, they can then be recommended for biological testing and see if there is evidence of Alzheimer's pathology,” Sano says.

Two blood tests were approved by the U.S. Food and Drug Administration in 2025 to help diagnose or rule out Alzheimer’s disease.

One can be used in a primary care setting and is designed to rule out the presence of amyloid plaques, a hallmark sign of Alzheimer’s disease. The sticky plaques can cause brain cells to die, so checking for amyloid in the brain helps doctors find out whether Alzheimer’s is the potential cause, according to the National Institutes of Health.

The other test is used for early detection of amyloid plaques. Both are for people 55 years old and older who have symptoms of the disease.

Can Alzheimer's Disease Be Prevented?

That's not been shown, but lifestyle factors may play a role in improving cognitive status, Sano says.

“I always say that people should ask themselves: Are they socially and intellectually active? Are they eating a healthy diet? And are they engaging in exercise?” she advises.

These habits are being studied to see if they might give people resilience against diseases that impair cognition, she adds.