Trauma from extreme climate events has long-term effects on survivors’ brains, study finds

People exposed to 2018 California wildfire showed ‘significant cognitive deficits,’ scientists say

Psychological trauma endured by survivors of extreme weather events like wildfires may have long-term impacts on their brains, according to a new study that reveals more on how the climate crisis affects cognitive functioning.

A growing body of studies and international governmental reports warn that as the global climate warms, extreme weather events like wildfires are becoming increasingly more commonplace.

For instance, the annual western forest-fire area in the US has increased by about 1,000 per cent in about three decades, with California now having a designated annual fire season.

Research has also revealed symptoms of anxiety and depression being common in communities impacted by California’s deadly 2018 wildfire.

The new research, published last week in the journal PLOS Climate, assessed whether some of the symptoms of psychological trauma related to the climate crisis affected people’s memory, learning, thinking and reasoning in the long term.

Studying cognitive effects this way has revealed the mechanisms behind some mental health symptoms. But there are still significant gaps in understanding brain function changes of people impacted by climate change.

Scientists, including those from the University of California, San Diego, assessed the cognitive functioning of participants across a range of abilities, including attention and working memory or one’s ability to maintain information in the mind for short time periods.

They also tested the subjects’ ability to not respond impulsively – or response inhibition – and their interference processing ability to ignore distractions.

Their brain function was also analysed while performing cognitive tasks by using brain wave recordings obtained from electroencephalography.

The study participants included three groups of individuals – those who were directly exposed to the 2018 wildfire, individuals exposed indirectly to the disaster and a control group that was not exposed.

Scientists found the groups directly and indirectly exposed to the fire dealt with distractions less accurately than the control group.

It was also found that people exposed to the wildfire had greater activity in their brains’ frontal lobes when they dealt with distractions.

“Fire-exposed individuals showed significant cognitive deficits, particularly on the interference processing task,” scientists wrote in the study.

Studies have shown that frontal lobe activity is a sign of cognitive effort, meaning people exposed to fires may have more difficulty processing distractions and compensate by exerting more effort.

“To the best of our knowledge this is the first study to examine the cognitive and underlying neural impacts of recent climate trauma,” researchers said.

Citing some limitations of the study, scientists said there was a possibility that the group differences observed in the research might have been present even before the traumatic wildfire event.

However, researchers still believe the findings provide first evidence of the chronic effects of climate trauma caused by wildfire.

“As the planet warms, more and more individuals face extreme climate exposures and hence, novel resiliency tools need to be investigated from multiple perspectives,” they concluded in the study.