Researchers at UC San Diego have discovered that individuals affected by the catastrophic Camp Fire in 2018 showed changes in cognitive function several months later. This is additional evidence of a rapidly emerging phenomenon referred to as “climate trauma.”
The Camp Fire, which occurred in November 2018, was the deadliest and most destructive wildfire in California’s history. It scorched a total area of 239 square miles, resulting in the destruction of 18,804 structures and the loss of 85 lives.
Three years after the devastating Camp Fire, a new study by scientists at the University of California San Diego explored the psychological impact of the disaster. The research found that exposure to “climate trauma” for those affected by the fire led to a heightened and persistent occurrence of mental health issues, such as post-traumatic stress disorder and depression.
In a new study, published in the journal PLOS Climate, senior author Jyoti Mishra, Ph.D., associate professor in the Department of Psychiatry at UC San Diego School of Medicine, director of the Neural Engineering and Translation Labs at UC San Diego, and associate director of the UC Climate and Mental Health Initiative, delved deeper with her colleagues. The study team reported that in a subset of persons exposed to the Camp Fire, significant differences in cognitive functioning and underlying brain activity were revealed using electroencephalography (EEG).
Specifically, the researchers found that fire-exposed individuals displayed increased activity in the regions of the brain involved in cognitive control and interference processing — the ability to mentally cope with unwanted and often disturbing thoughts.
“To function well day-to-day, our brains need to process information and manage memories in ways that help achieve goals while ignoring or dispensing with irrelevant or harmful distractions,” said Mishra.
“Climate change is an emerging challenge. It is already well-documented that extreme climate events result in significant psychological impacts. Warming temperatures, for example, have even been linked to greater suicide rates. As planetary warming amplifies, more forest fires are expected in California and globally, with significant implications for mental health effects.
“In this study, we wanted to learn whether and how climate trauma affected and altered cognitive and brain functions in a group of people who had experienced it during the Camp Fire. We found that those who were impacted, directly or indirectly, displayed weaker interference processing. Such weakened cognitive performance may then impair daily functioning and reduce wellbeing.”
The study sample included 27 persons directly exposed to the Camp Fire (for example, their homes were destroyed), 21 who were indirectly exposed (they witnessed the fire, but were not directly impacted), and 27 control individuals. All participants underwent cognitive testing with synchronized EEG brain recordings.
Sixty-seven percent of the individuals directly exposed to the fire reported having experienced recent psychological trauma, as did 14 percent of the indirectly exposed individuals. None of the control individuals reported recent trauma exposure.
The EEG recordings showed that the brains of those individuals reporting trauma worked harder at interference processing and cognitive control, suggesting a compensatory effort but at a cost: potentially heightened risk of neurological dysfunction elsewhere.
“The evidence of diminished interference processing, along with altered functional brain responses, is useful because it can help guide efforts to develop resiliency intervention strategies,” said Mishra.
“As the planet warms, more and more individuals will face extreme climate exposures, like wildfires, and having therapeutic tools that can address underlying neuro-cognitive issues will be an important complement to other socio-behavioral therapies.”
Reference: “Differences in interference processing and frontal brain function with climate trauma from California’s deadliest wildfire” by Gillian K. Grennan, Mathew C. Withers, Dhakshin S. Ramanathan and Jyoti Mishra, 18 January 2023, PLOS Climate.
The study was funded by the Tang Prize Foundation.