I lost me.

You lost yourself?

Yeah.

Where did you go?

I don’t know. I don’t have a sense of who I am.

Marc Pierrat’s mind once ran as smoothly as the gears on his endurance bike. He was a mechanical engineer by training and a marathoner for fun, a guy who maintained complicated systems at work and a meticulously organized garage at his Westlake Village home.

Three years after his diagnosis of frontotemporal dementia, Marc’s thoughts are a jumble he can’t sort out alone. Once-routine tasks are now incomprehensible; memories swirl and slip away. His wife, Julia Pierrat, 58, shepherds Marc, 59, through meals and naptime, ensures he is clean and comfortable, gently offers names and words he can’t find himself.

It is often impossible for a person to talk about the internal experience of living with FTD, either because they can’t accurately assess their internal state or don’t have the language to describe it. In many cases the disease attacks the brain’s language centers directly. In others, a common symptom is loss of insight, meaning the ability to recognize that anything is wrong.

But minds can unwind in a million different ways. In Marc’s case, the disease has taken a path that for now has preserved his ability to talk about life with what one doctor called “the most difficult of all neurologic diseases.”

Thousands of people in the U.S. live with FTD. Marc can speak for only one of them, and at times he does so with clarity that breaks his wife’s heart. Occasionally Julia records snippets of conversation with his permission, mementos from a stage of marriage they never saw coming.

“It feels like walking into a closet you haven’t been in in a while, and you’re looking for something that you know is there, but you don’t know where,” Marc said recently, as Julia looked on.

“And then, you know, you just — yeah. You just give up,” he concluded. “It’s the giving up part that’s hard.”

Marc takes a selfie with his wife, Julia before Marc was diagnosed with FTD.

(Pierrat family)

Do you know the name of the disease that you’re living with?

Yes.

What is it called?

Frontotemporal dementia.

Yep, that’s exactly right.

FTD, for short.

How does it affect you?

Well, I guess, processing of inputs tend to, in a normal mind — they get processed efficiently to a decision. Like, if you’re going to catch a ball, you know, you have the ball in the air, [and] you have to raise your arm and your glove, and you catch the ball. And FTD interferes with all of that. So it makes it harder to catch the ball.

More than 6 million people in the U.S. currently live with dementia, an umbrella term for conditions affecting memory, language and other cognitive functions.

Up to 90% of dementia cases are caused by Alzheimer’s disease, the progressive memory disorder, or by strokes and other vascular problems that disrupt blood flow to the brain. The rest arise from a variety of lesser-known but equally devastating conditions. Frontotemporal dementia is one of them.

After putting Marc in bed for an afternoon nap, Julia spends a quiet moment in the kitchen of their home in Westlake.

In FTD, abnormal proteins accumulate in the brain’s frontal or temporal lobes, damaging and eventually destroying those neurons. It’s frequently misdiagnosed, and so the number of current U.S. cases is hard to pin down — estimates place it between 50,000 and 250,000 people.

By far the best-known person living with FTD is the actor Bruce Willis, whose family disclosed his diagnosis in 2023.

Willis has primary progressive aphasia, the second-most common form. In his case, the most damaged tissues are in his brain’s left frontal or left temporal lobes, which play crucial roles in processing and forming language. One of his first noticeable symptoms was a stutter, his wife Emma Heming Willis has said in interviews; he now has minimal language ability.

But FTD is highly heterogeneous, meaning that symptoms vary widely, and it has affected Marc and Willis in very different ways.

The disease has several subtypes based on where the degeneration begins its advance through the brain.

Marc Pierrat dances with activity counselor Rhoda Nino who leads a class at Infinity Adult Day Health Care Center in Westlake Village.

Pierrat has the most common subtype, behavioral variant FTD. His disease has targeted his frontal lobes, which manage social behavior, emotional regulation, impulse control, planning and working memory — essentially, everything a person needs to relate to others.

FTD typically presents between the ages of 45 and 60. Because it shows up so much earlier than other dementias, its initial symptoms are often mistaken for other conditions: depression, perimenopause, Parkinson’s disease, psychosis.

Everything we think and do and say to one another depends on very specific physical locations in our brains functioning correctly. Behavioral variant FTD strikes right at the places that house our personalities.

When an eloquent person suddenly can’t form sentences, it’s typically seen as a medical problem. But when an empathetic person suddenly withholds affection, it’s perceived as an act of unkindness. The truth is that both can be the product of physical deterioration in a previously healthy brain.

If you were to describe to another person what it’s like to live with FTD, how would you describe it?

Oh my God. . . . Well, you can’t assess situations accurately. You see a train coming, and it’s gonna smash into your car, and you’d be, like, ‘Oh. Huh. That train’s gonna hit my car.’ And there’s nothing you can do.

The first sign came in late 2018. Marc, then 52, was in a fender-bender a few blocks from home and called Julia for a ride. When she arrived, he was not just surprised to see her, but angry. Why was she there? Who’d asked her to come?

She was taken aback by his forgetfulness, and more so by his hostility. Marc could be stubborn and confrontational; over the decades, they’d argued as much as any couple. But this outburst was out of character. She chalked it up to nerves.

Marc was a respected project manager in the pharmaceutical industry. He spent weekends on home improvement projects or immersed in his many hobbies: hiking, woodworking, 100-mile bike races.

Marc, Julia (right), and their daughter take a selfie on the Golden Gate Bridge during a bike ride.

(Pierrat family)

Julia was a business manager with Dole Packaged Foods. Their daughter was pursuing a doctorate at UCLA. The couple enjoyed life as empty nesters with shared passions for road trips and camping.

For a year or two after the accident, nothing happened that couldn’t be dismissed as a normal midlife memory lapse or a cranky mood. But by late 2020, something had undeniably changed. The harsh parts of Marc’s personality ballooned to bizarre proportions, smothering his kindness, generosity and curiosity.

He lost a phone charger and accused Julia’s mother of stealing it. He misplaced his binoculars and swore his sister took them. The neighbors asked the Pierrats to trim their gum trees and Marc flew into a rage, ranting about a supposed plot to spy on them.

His work performance and exercise habits appeared unaffected, which only made his outbursts more confusing — and infuriating — to Julia.

“At the beginning of the disease nobody knew he had any issue, other than he seemed like a total jerk,” she recalled.

The Pierrats did not know they were at the start of a chaotic period distinct to sufferers of FTD’s behavioral variant.

Julia laughs as Marc he squeezes by on a narrow bridge at the Foxfield Riding School in Lake Sherwood.

“Everything that can affect relationships is at the center of the presentation of the behavioral variant,” said Dr. Bruce Miller, director of the UC San Francisco Memory and Aging Center. “The first instinct of a spouse or a child or a human resource program or a psychiatrist [is to] assume a psychiatric problem.”

People with the condition start to lash out at loved ones or lose interest in lifelong relationships. They may snarl at strangers or shoplift at the mall. They consume food or alcohol obsessively, touch people inappropriately or squander the family’s savings on weird purchases.

And at first, just like in the Pierrats’ case, nobody understands why.

“When someone is not who they were, think neurology before psychology,” said Sharon Hall, whose husband Rod — a devoted spouse who delighted in planning romantic surprises — was diagnosed in 2015 after he started drinking heavily and sending explicit texts to other women.

At Julia’s insistence Marc visited his doctor in July 2021, who referred him to a neurologist. He would spend the next year making his way through a battery of appointments, scans and cognitive testing.

In the meantime, his life disintegrated.

Marc and Julia with their family dogs prior to his diagnosis with FTD.

(Pierrat family)

Just a few years earlier, bosses and colleagues praised Marc as a superlative manager. In January 2022 he was put on notice for a host of causes: combative emails, obnoxious behavior, failures of organization.

At home he botched routine fix-it jobs, missed crucial appointments and got lost on familiar routes. He stopped showering and called Julia appalling names. She went to therapy and contemplated divorce.

Finally, on July 18, 2022, the couple sat across from a neurologist who delivered the diagnosis with all the delicacy of an uppercut.

There was no cure, he told them, and few treatment options. He handed them a pamphlet. Marc showed no emotion.

In the car Julia sobbed inconsolably as Marc sat silent in the passenger seat. Eventually she caught her breath and pulled out from the parking lot.

Do you like being married?

Yes, I do.

Why?

It makes me a better person.

That’s so sweet. How do you think it makes you a better person?

Being able to talk to you and, you know, resolve through different problems together. I mean, it’s good to have an extra mind.

They left the neurologist with nothing: no instructions, no care plan, not even the stupid pamphlet, which was about memory problems in general. “It was diagnose and adios,” Julia said. “I hit the internet immediately.”

Julia now had three different roles: her paid job, Marc’s 24-hour care, and a part-time occupation finding support, services and answers.

Marc tries to figure out what he would like for lunch as Julia offers suggestions at the Joi Cafe in Westlake.

She insisted Marc fill the neurologist’s prescription for an anti-anxiety medication that diminished his irritability and agitation without zonking him out.

She found an eldercare attorney, and together she and Marc organized their legal and financial affairs while he was still well enough to understand what he was signing. Through Facebook she found her most valuable lifeline, a twice-weekly Zoom support group for caregivers.

She went on clinicaltrials.gov, a database of studies run by the U.S. National Institutes of Health, and FTDregistry.org, which lists trials specific to the disease, and signed the two of them up for every study they qualified for.

Marc was accepted into AllFTD, a longitudinal study that is the largest ever conducted for this disease. The couple travels yearly to the University of Pennsylvania’s FTD Center for tests that track changes in his symptoms and biomarkers, with the goal of contributing to future therapies and preventive treatments.

Marc paints a bird house during an art class at Infinity Adult Day Health Care Center in Westlake Village.

She found the website of the nonprofit Assn. for Frontotemporal Degeneration. Eventually she became a volunteer AFTD ambassador, speaking and advocating for families affected by the disease. In August, she posed for a group photograph at the state capitol with Emma Heming Willis and other FTD advocates who traveled to Sacramento to meet with state lawmakers.

All of it is a way of finding purpose in pain. FTD has dulled Marc’s emotional reactions, leaving Julia to carry the full weight of their grief.

“He grasps the impact, but somehow the emotion is buffered,” she said. “I lose it sometimes. I cry my eyes out, for sure. I feel the full emotional impact of it, in slow motion. . . . There’s no blunting it for me.”

Julia helps Marc up from a couch on the back patio of their home in Westlake.

These days the Pierrats rise around 6 a.m., eat the breakfast Julia prepares, and then Marc takes his first nap of the day (fatigue is a common FTD symptom). When he wakes around 9 a.m. Julia makes sure he uses the bathroom, and then drives him to a nearby adult daycare program where he does crafts and games until lunch. He sleeps for another few hours at home, spends two hours in the afternoon with a paid caregiver so that Julia can do errands or exercise, and then the couple eats dinner together before Marc beds down by 8 p.m.

When they are awake together, they go for walks around the neighborhood or to familiar cafes or parks. The hostility of the early disease has passed. They speak tenderly to one another.

At each sleep, Julia walks him upstairs to the bedroom they used to share. She tucks him in and gives him a kiss. At night she retires to a downstairs guestroom, because if they share a bed Marc will pat her constantly throughout the night to make sure she’s still there.

My clock’s ticking. I could die any day.

Do you feel like you’re going to die any day? Or do you feel healthy?

I feel kind of healthy, but I’m still worried. Because I have something that I can’t control inside of me.

About two years ago, Julia and Marc were on one of their daily walks when she realized they had already had their last conversation as the couple they once were, with both of them in full possession of their faculties. In one crucial sense, Marc was already gone.

Julia makes sure Marc is comfortable for his afternoon nap at their home in Westlake.

But in other ways, their connection remains.

“The love that we have is still completely there,” she said recently in the couple’s backyard, while Marc napped upstairs.

“When you’re married to someone and you’ve been with someone for so long, you almost have your own language between you. He and I still have that.”

She looked out over the potted succulents and winding stone pathways they had spent so many weekends tending together.

“A lot of our relationship is preserved in spite of it, which is just so interesting, [and] also makes it more heartbreaking,” she continued. “Because you know that if the disease plays out like it is expected to, you will just continue to slowly lose pieces.”

The average life expectancy for people with Marc’s type of FTD is five to seven years after diagnosis. Some go much sooner, and others live several years longer.

At the moment, all FTD variants lead to a similar end. Cognition and memory decline until language and self-care are no longer possible. The brain’s ability to regulate bodily functions, like swallowing and continence, erodes. Immobility sets in, and eventually, the heart beats for the last time.

But until then, people keep living. They find reasons to keep going and ways to love one another. The Pierrats do, anyway.

Marc and Julia visit horses at the Foxfield Riding School in Lake Sherwood.

On a recent morning, the couple strolled through a nearby equestrian school where their daughter once took lessons. Julia brought a baggie of rainbow carrot coins she’d sliced at home. She showed Marc how to feed the horses, as she does at every visit.

“Hold your hand completely flat, like I’m doing,” she said gently.

“I don’t want to lose a finger,” Marc said as a chestnut horse nuzzled his palm.

“You’re not going to lose a finger,” Julia assured him. “I won’t let that happen to you.”

Marc and Julia walk hand-in-hand after visiting horses at the Foxfield Riding School in Lake Sherwood.

If you are concerned about a loved one with dementia or need support after a diagnosis, contact the Assn. for Frontotemporal Dementia helpline at theaftd.org/aftd-helpline or (866) 507-7222 Monday through Friday from 9 a.m. to 5 p.m. EST.