Media release

From: PLOS

How cumulative heat exposure affects students

A systematic review synthesizes research on the long-term effects of heat on cognitive performance

A holistic approach reveals the global spectrum of knowledge on the impact of cumulative heat exposure on young students, according to an article published July 30 in the open-access journal PLOS Climate by Konstantina Vasilakopoulou from the Royal Melbourne Institute of Technology, Australia, and Matthaios Santamouris from the University of New South Wales, Australia. The article aims to shed light on the social and economic inequalities caused within and across countries, the potential adaptive measures to counterbalance the impact of overheating, and forecasts about the cognitive risks associated with future overheating.

Exposure to elevated temperatures, both indoors and outdoors, is strongly associated with adverse health outcomes. The impact of high temperatures and heat stress on human productivity and cognitive performance is well-documented. Most studies indicate that exposure to excessive heat detrimentally affects working memory, information processing, and knowledge retention, thereby impairing overall cognitive performance. The impact of high temperatures on students’ academic performance is profound, influencing their educational, intellectual, and professional achievements.

Although there is a plethora of investigations on the momentary and short-term exposure of students to heat and its effects, there is a lack of knowledge and information on the impact of long-term exposure on student cognitive performance. Given the rapid increase in temperature caused by global and regional climate change, understanding the consequences of cumulative exposure to high temperatures on the cognitive ability of students is an urgent priority.

To address this knowledge gap, the authors reviewed seven studies, described in six peer-reviewed articles, that investigated the effects of prolonged heat exposure on students’ cumulative cognitive performance. Collectively, these studies covered an extensive dataset comprising nearly 14.5 million students from 61 countries, linking individual learning outcomes to heat exposure. Overall, the findings suggest that long-term heat exposure negatively impacts students’ cumulative learning, with complex tasks (e.g., mathematics) more affected than simpler ones (e.g., reading).

Six of the seven studies identified a significant negative relationship between extended heat exposure and cognitive performance, while one study found the impact to be minimal. Adaptation via acclimatization and increased air conditioning use showed protective effects. However, lower socioeconomic groups faced disproportionately greater impacts, underlining critical inequalities.

According to the authors, impairments related to cognitive and human capital loss of the young generation may affect the future progress of nations because of the associated dramatic economic, social and cultural implications caused by persistent disruptions to the learning process. The social cost of global overheating will unfortunately affect equity and the quality of life of the vulnerable low-income population. It will accelerate societal discrepancies and will impede economic progress in less developed countries suffering from excessive heat exposure. There is an urgent need to adopt a new perspective on the cognitive implications of climate change by advancing technologies and implementing robust, targeted policies to safeguard both current and future human capital.

The authors add: “This study critically reviewed the existing literature on the effects of long-term heat exposure—primarily driven by climate change—on students’ cognitive performance. Prolonged exposure to elevated temperatures was consistently linked to reduced learning outcomes, particularly in tasks that require complex cognitive processing, such as mathematics. The findings revealed that students in socioeconomically disadvantaged areas are disproportionately affected. Factors contributing to this disparity include higher localized temperatures in low-income communities, limited access to air conditioning at school and at home, and fewer opportunities for academic support services like private tutoring to offset learning losses. Projected climate scenarios indicate that these disparities will only deepen over time, further disadvantaging already vulnerable student populations. To mitigate these effects, the literature highlights several adaptive strategies to enhance learning conditions—such as implementing indoor and outdoor cooling systems and improving classroom ventilation.”

They summarize: “This review, conducted over the course of a year, examined a comprehensive range of sources on the subject. The evidence underscores how global warming can produce far-reaching and often overlooked social consequences. Most critically, it reiterates that those bearing the brunt of climate change's impacts are often those least responsible for it—and least equipped to combat its effects.”