Ever feel like things are moving too slowly when there's too much heat? Well, a new Harvard study says heat waves not only make things seem slow, but they might also be causing our cognitive function to slow down.

In other words, heat waves make people a little bit dumber, at least according to the researchers' findings.

Do Heat Waves Cause People To Be Dumb?

The study, conducted by the Harvard TH Chan School of Public Health and published in the PLOS Medicine journal, examined cognitive performance among students who lived in buildings without air conditioning and those who had them. It was conducted during the 2016 heatwave in Boston.

The researchers discovered that the students without air conditioning showed a 13 percent longer reaction time when it came to cognitive tests as opposed to the students who had proper, comfortable ventilation. Not only that, but the well-ventilated students were also more accurate when it came to answering those tests.

Thus, the study suggests that cognitive function might be affected by an increase in "thermal load," alongside the combined influence of other factors related to heat exposure, particularly loss of sleep and dehydration.

Why Knowing The Effects Of Heat Exposure Is Important

Lead author Jose Guillermo Cedeño-Laurent says that knowing the risks of extreme exposure to heat is critical, especially considering that in a number of cities, heat waves are expected to worsen due to climate change. Observing the effects of indoor temperature is also just as important, since Americans spend 90 percent of their time lodged inside their homes.

Extreme heat waves can cause grave consequences on public health and it's also the leading cause of death of all meteorological phenomena in the United States, according to the researchers. Globally, temperatures are rising, with 2016 being the warmest year on record for the past two centuries.

The impact of heat on health has been studied many times before, but most of those studies focused only on vulnerable populations, such as the elderly or the very young. This study, however, studied people in their late teens or early 20s living in dorm rooms, and it shows that heat waves possibly cause effects in mental performance, too, and not just in terms of physical aspects.

That being said, a 13 percent difference in terms of cognitive ability doesn't seem to be that drastic, and the study is somewhat limited because it only looked at less than a hundred people. Further research is needed to see whether their results will hold in a larger-scale setting.