Effects of excessive heat on the brain

Although the majority of climate scientists firmly believe that the climate is warming unsustainably, a sizable portion of the public is convinced that global warming concerns are overblown—contrary to proven scientific evidence as well as everyday observations.

In 1988, experts testified in Congress at the first congressional hearing climate change. Every year in the 21st century has been warmer than 1988, and every decade has been warmer than the previous one. The last three years from 2023 to 2025 were the hottest on record. get to know From 1850, when sufficiently direct measurements by instruments (thermometers) made it possible to estimate temperature. The last 11 years include all the warmest years observed using instrumental methods.

But you don’t have to look to extremes of temperature to come across compelling evidence that even less extreme examples can affect the proper functioning of the human brain. If we stick to the temperatures we’ve already experienced, especially in 2023, 2024 and 2025, there’s more to worry about.

Effects of heat on the brain

In general, even moderate heatstroke can negatively affect the brain’s ability to think and think patterns. As the temperature and duration of a heat wave increases, the brain’s neurotransmitters experience disruptions in signal transmission. neuron to the next one. In response, the receiving neurons can fire very quickly, very slowly, somewhat irregularly—it doesn’t matter which; the results are mood-altering, memorythinking and sleeping. In addition, electrolyte loss from sweating leads to weakness, muscle cramps and, in some cases, seizures. Exposure to extra heat affects cognition and behavior, especially clarity of thought, sustained attention, memory, and speed decision making.

Perhaps the most surprising are subjective mental experiences. Think of the last time you were trapped in a “heat wave,” even of moderate intensity by today’s standards (90-100 degrees Fahrenheit). You were, no doubt, fully occupied with your discomfort; you can’t think of anything else. In response to heat-induced lethargy and restlessness, your concentration was almost nil, and you “can’t think straight—a colloquial expression for losing clarity and precision.

In such circumstances, productivity Once you’re preoccupied with the thought of somehow moving to an air-conditioned environment, it plummets. If the humidity has also increased (eligible for the description of “like” in weather data), the effect of to know was even greater.

If the temperature rises three times, a person may experience the first symptoms of “heat stroke”. But let’s not go there. Let’s stick to the temperature issues that most of us have faced and will surely face again.

Heat and frontal lobe changes

Most of the heat-related brain changes are caused by the effects of heat on the frontal lobes, which are located in the farthest front of the brain. The frontal lobes are responsible for, among other things:

1. Sequencing (keeping bits of information in order).
2. Executive control (planning combined with anticipation of the consequences of our actions).
3. Self-analysis (the ability to imagine ourselves in the future based on our current actions).

Disorders of the frontal lobes lead to difficulties in planning, poor decision-making, difficulty changing thoughts, distraction and impulsivity.

Examples of heat-induced impairments in frontal thinking and judgment include accidents such as swerving a car in front of an oncoming driver in a “failure to show” violation that can lead to a car accident. In cooler conditions, the driver would have stopped and turned only after the other vehicle had passed.

Regardless of the specific examples, the principle of operation remains the same: The quality of our thinking always depends on the temperature. Passing the test shows the effect of heat on cognitive function. Scores on cognitive tests drop sharply with increasing temperature: an increase of 4 degrees (perceived by the tester as a slight discomfort) leads to a 10% decrease in performance on tests of memory, reaction time and reasoning. Other studies have shown a .3% decrease for every 1 degree increase in temperature above 72 degrees. In general, the warmer the average daily temperature during a typical school year, the worse students perform on standardized tests.

But it affects not only the quality of thinking, but also the ability to control our anger. Decades of research have shown that as temperatures rise, so does disorder. domestic violenceand aggravated assaults.

Among the less serious consequences, experiments have shown that at high temperatures, heat-affected drivers telegraph the installation. anger leaning on car horns. When this ear-splitting cacophony reaches a certain intensity, many of the hitherto uninvolved drivers respond by honking their horns.

When experts try to describe the causes of violence, socioeconomic, geographic and racial disparities are quickly listed, but rising temperatures receive little attention. For example, the 2024 US Surgeon General’s report, Gun Violence: America’s Public Health Crisis, does not cite global warming or heat waves as a cause of violence.

Coping with heat waves

Explaining heat waves is not as important as responding to them. Special precautions will be needed if heat records continue to be similar to those seen in 2023-2025. The most common, of course, is air conditioning and taking enough cooling drinks.

New portable cooling fans on stage. You’ve probably seen them in lounges and nightclubs. Although these devices can make the user feel cooler, both literally and figuratively, as with fans of any size, the amount of heat reduction offered is strictly limited. Cooling devices that involve direct contact of cooled liquids with the skin are much more effective.

Such devices were first used in Afghanistan and Iraq among combat troops equipped with freeze packs placed in strategic locations under body armor. Further development of the concept resulted in “plastic plates” that fit the contours of the human body. In the 2027 Formula 1 season, drivers will have to wear such “cooling vests” or ice packs. Similar products are already available on the market for general use.

All of this raises an important question: if some of us are looking for portable body coolers in “unbearable” temperatures, where do we turn if the resistors go wrong (as I suspect) and the temperature continues to rise?

According to the Canadian Center for Climate Modeling and Analysis (CCCma), this is not a surprise: “2026 is likely to be among the four warmest years compared to 2023 and 2025, and will approach 2024 as the hottest year on record.”

It’s March now – only 6 months or so until we know who’s right, climate scientists or naysayers. Reluctantly, and with an admittedly foreboding feeling, if I were a betting man, I now know where I’d place my bet.