Heat waves mess with your brain. Scientists are trying to figure out why.

A dangerous heat wave has impacted Western Europe this week, with the UK recording its highest ever June temperature at 36.1 °C (97 °F) on June 12, 2024. This extreme heat is not only causing widespread concern for public health and infrastructure but is also affecting cognitive functions, making it difficult for individuals to think clearly. Researchers are actively investigating the precise mechanisms by which high temperatures impact the brain. Studies have established a correlation between rising temperatures and increased irritability and aggression, although these findings are largely based on associations. Catherine Thompson, a cognitive psychologist at Liverpool Hope University, is conducting research on the effects of extreme heat on firefighters. Her team's preliminary findings indicate that firefighters experienced a decline in their ability to focus and control attention immediately following exposure to intense heat during training exercises. These cognitive impairments resolved within approximately 20 minutes of cooling down after a 15-minute heat exposure period. Thompson's work aims to provide a more direct understanding of how heat affects cognitive skills, which could offer insights into the broader population's experience during heat waves.