'Fire brain': Survivors of wildfires describe cognitive struggles

Many people escaped the deadly Maui wildfires - some in harrowing fashion - but their ordeal may not be over.

The harmful effects of wildfire exposure don't disappear once the flames are extinguished, experts said. There is growing research that suggests breathing in the tiny particles from wildfire smoke can produce cognitive deficits, which may appear in as little as six to 12 months or even years later.

Surviving a near-death experience also raises the risk of post-traumatic stress, with such symptoms as depression, sleep disorders, anxiety and survivor's guilt, researchers said.

"Of course, the immediate most important thing is to survive," said Marc Weisskopf, professor of environmental epidemiology and physiology at Harvard T.H. Chan School of Public Health, who studies the relationship between air pollution and brain health. "But unfortunately, those who do survive also may be vulnerable to both long- and short-term effects on the brain caused by this exposure."

Some survivors of wildfires describe their cognitive struggles after escaping the blaze as "fire brain."

Living with 'fire brain'

Randy Gerhardt, 66, and wife Sandi Knapp Gerhardt, 55, fled the 2018 Camp Fire in California, the deadliest and most destructive in that state's history, and noticed changes in themselves almost immediately. They would have clear mental pictures of an item they would be looking for - a tool, a lawn game - but couldn't recognize the new item they replaced it with. Other times, they would walk into a room and not know why they were there.

Gerhardt, a retired salesman for Frito-Lay, had been used to a busy work schedule and just as robust slate of projects and hobbies. After the fire, he couldn't finish tasks, let alone get enough motivation to start them.

"I didn't know what was wrong with me," Gerhardt said. "I built seven houses, helped build two churches. Used to work 65-70 hours a week."

The couple chalked up their new behavior to stress. "But this was different than just stress," Gerhardt said. "You wonder why you're being so worthless and lazy. I'd have a list and not feel like doing any of it. Even my bills, I'd just let them sit there for a month."

Even rebuilding a home in Paradise took Gerhardt an uncharacteristically long two years. "All my friends would ask, 'how is the house coming?' and I just wouldn't work on it," he said.

For a period of two years after the fire, Gerhardt and his wife met weekly with five other couples who were living in trailers set up on the property of a tile factory owned by a friend. The group, who dubbed themselves "the forever friends," would talk and exchange information and what they were going through.

He thinks it was in that group that someone first mentioned to him the idea of "fire brain." In chats with emergency room doctors since then, he was given further confirmation that what he was experiencing was not only real but also common among some fire survivors.

Having his feelings and behaviors named made him feel less broken, he said.

"I felt vindicated," he said. "I wasn't crazy. What I was going through was normal, I wasn't weaker."

Trauma related to climate change

Trauma from surviving natural disasters related to climate change is also different from other one-time events such as a car accident or sexual assault, said Dhakshin Ramanathan, associate professor in residence in psychiatry at the University of California at San Diego.

"People see the environment as a refuge, a positive healing thing," he said. "When something you see as positive turns against you, that's a difficult thing for many people to deal with."

There is added stress from not being able to predict whether survivors will be exposed again. "Climate will be a sustained stress that will be harder to treat," Ramanathan said.

One study conducted after the Camp Fire found that more than 30 percent of those directly exposed had symptoms of post-traumatic stress, "and these symptoms were three times more prevalent than in non-exposed communities on the West Coast," said Jyoti Mishra, lead author and associate professor of psychiatry at the UC-San Diego.

"Indirectly exposed individuals, that is, those who lived in the community where the wildfire happened, were also affected by PTSD but to a lesser extent than directly exposed individuals," she said.

Laura Nelson, 39, fled the Camp Fire with her cat, dog and bearded lizard hoping to find a quick exit by car. Instead, she was stuck in a massive traffic jam along Paradise's Skyway as the fire raced uphill.

"I thought I was going to die in a line of cars for four hours," Nelson recalled.

With no close family nearby, she lived in her car for several months before settling in Oregon where she began experiencing tinnitus, vertigo, intrusive thoughts and nightmares.

"In Oregon, part of the mental health effects I was experiencing was isolation, it was being misconceived," said Nelson, whose new community could not understand why she found traffic jams or the smell of smoke triggering.

She struggled to reconcile with the reality that her possessions had been destroyed in the fire, often bypassing items at the mall because she believed she still had a particular fork or sweater or belt. Beyond what she described as a kind of brain fog, symptoms of her worsening mental health emerged later, including thoughts of suicide.

"I was totally alone," Nelson said. "It became very overwhelming and isolating, and you think of things that you've never thought of before." Doctors prescribed medication, but there was no pill for what she needed.

"I didn't have a disease," Nelson said. "I had trauma."

There also is guilt, along with increased anxiety and depression, experts said. "Survivors often feel they should have done more to help others, which can be psychologically damaging and guilt-producing - and totally irrational," said Andrea Roberts, senior research scientist in environmental health at the Chan school, who was not involved in the Camp Fire study. "In most cases, there is nothing they could have done."

Cognitive deficits after escaping wildfire

The Camp Fire study also looked at cognitive functioning within six months to a year after the fire, using the Flanker task, which measures the ability to suppress distractions while focusing on a task. They found a 20 percent deficit among those who had been exposed to wildfires compared with those who had not.

"Breathing in particulate matter can lead to inflammatory responses in the body," Mishra said. 'That affects brain processes. How it influences brain processes is still a question."

When the researchers looked at brain function underlying specific cognitive functions, they found heightened activity in the left frontal part of the brain that was more pronounced in those exposed to wildfires, she said.

"It's overprocessing all the stimuli coming at you," Mishra said. "That's what happens in traumatized brains."

These results are consistent with the "common trajectory" of mental health that follows a traumatic event, said Irva Hertz-Picciotto, professor of public health sciences and director of the environmental health sciences center at the University of California at Davis, who was not part of the Camp Fire study.

"Often people go into high gear in the immediate aftermath, where the need to get into survival mode is intense, and all systems are on high alert, and that can last for months," she said. "But at some point, it is too much to sustain, and people crash, often around six months where they may sink into a deep depression."

Smoke particles that cause brain inflammation

Until recently, scientists focused more on how inhaling tiny smoke particles affected the cardiovascular and respiratory systems than the brain, said Kent Pinkerton, professor of pediatrics at the UC-Davis school of medicine, who studies how vapors, gases, particles and fibers affect respiratory, cardiovascular and neurological functions.

Breathing through the nose in stressful conditions is good, he said, because it serves as a filter, and "the particles will deposit in your nose, rather than deep in the lungs." At the same time, though, cells responsible for the sense of smell can carry the particles to the brain and produce inflammation, Pinkerton said.

Inflammation - when it becomes chronic - can be dangerous.

"Wildfire exposure is so intense that it causes neuroinflammation on a rapidly occurring scale," Weisskopf said. "The initial inflammation is actually a protective response - like when you have a fever or injury - but in some people, it can become chronic. The longer it lasts, the more likely you are to have more long-lasting effects."

Also, toxic metals often are "hitchhiking" on these tiny particles, said Ray Dorsey, the professor of neurology at the University of Rochester.

"If you look at the brains of people with Alzheimer's disease and Parkinson's, you find higher concentrations of these toxic metals: lead, iron from brake pads, platinum from catalytic converters," he said. "They are probably bypassing the blood-brain barrier. The nose may be the front door in exploiting the normal protective mechanisms of the brain."

The effects of trauma probably influence future brain disease, experts say. "PTSD is a major risk factor for later dementia, though it is years later, not next year," said Paul E. Schulz, professor of neurology and director of the Neurocognitive Disorders Center at UTHealth Houston.

The effects of inhaling wildfire smoke, compounded by trauma, sets up a complicated mystery scientists need to explore further, Mishra said.

"There are all these jigsaw puzzle pieces," she said. "The particulates enter the brain system and can cause inflammation. We know this can interact with emotions and cognitive systems in the brain. But in the context of wildfires, we don't know yet how all this comes together."