Summer Heat Is Slowing Your Brain Down

July 25, 2018

© Jorgosphotos |


We tend to move a little slower when it's super hot. And apparently our brains do, too!

"There's evidence that our brains are susceptible to temperature abnormalities," says Joe Allen, co-director of the Center for Climate, Health and the Global Environment at Harvard University. Allen and his colleagues studied college students living in dorms during a summer heat wave in Boston. Half of the students lived in buildings with central AC, where the indoor air temperature averaged 71 degrees. The other half lived in dorms with no AC, where air temperatures averaged almost 80 degrees.

The students were sent two tests per day on their cell phones, for nearly two weeks. One test included basic addition and subtraction; that measured cognitive speed and memory. The second test assessed attention and processing speed. "We found that the students who were in the non-air-conditioned buildings actually had slower reaction times: 13 percent lower performance on basic arithmetic tests, and nearly a 10 percent reduction in the number of correct responses per minute," said Allen.

Another study found that when office temperatures rise above the mid-70s, workers' performance begins to drop off. Researchers reviewed multiple studies that evaluated performance on common office tasks. The study found that worker productivity is highest at about 72 degrees. When temperatures exceeded the mid-80s, worker productivity decreased by about 9 percent.