The Weight of Nature: How a Changing Climate Changes Our Brains

This novel inquiry from Aldern (coauthor of Homelessness Is a Housing Problem), a Grist data reporter and former neuroscientist, examines how global warming will affect human cognition and behavior. Heat influences decision-making, Aldern argues, noting research that found the likelihood that a judge will grant migrants asylum decreases as the temperature rises. Another study showed that heat stymies the effectiveness of the brain’s serotonin system, making people more impulsive and aggressive. Other evidence is more circumstantial. For instance, Aldern points out theories suggesting the act of forgetting evolved “to update our beliefs so we can best navigate the world as it changes.” In light of this, he predicts that as the environment transforms, people’s brains will recognize that their current climate doesn’t accord with the weather as featured incidentally in countless memories, leading the brain to suppress them to establish more accurate, up-to-date expectations. The most devastating portions of the book profile individuals coping with the cognitive consequences of climate change, such as Michael Reed, who has had PTSD since his wife and two children died in a Tennessee wildfire in 2016. Though the more speculative arguments remain open to debate, research on the deleterious psychological effects of severe heat offers a unique perspective on how humans will be changed by a warming world. Readers will be troubled. Agent: Larry Weissman, Larry Weissman Literary. (Apr.)