Women typically do mental tasks better in warm rooms: Heat affects cognition and equality

Women perform better on math and verbal tests at higher temperatures while men perform better at lower temperatures, according to a laboratory study^[1] on German students. The research also found that the gain in cognitive performance for women is higher than the loss in men’s as the temperature rises. As the room temperature rose, men’s performance declined and women’s performance improved.

Their findings open the doorway to develop more thoughtful regulations and norms regarding office temperatures, school temperatures, testing environments, teamwork, and dress codes.

A 2012 review of studies^[2] found that women are 1.74 times more likely to be dissatisfied with the temperature than men, especially at the cooler end; they are also more sensitive to extreme deviations from a neutral temperature. Typically, women prefer 24-25 degrees centigrade and men prefer 21-22 degrees centigrade. A report in Nature^[3] shows that office temperatures are usually biased toward men. These insights raise important questions – Is the ambient temperature in offices and schools really appropriate? Are room temperatures unfairly biased toward men’s preferences at the cost of women’s productivity and satisfaction? Are office temperature decisions sexist? Are clothing restrictions or dress codes an obvious hurdle to overcome this problem?

Turns out, cold workplaces and learning/testing centers may be putting women at a significant yet preventable disadvantage.

Women are 1.74 times more likely than men to be dissatisfied with temperature, especially when it's cold and they perform mental activities better at higher temperatures. Is the temperature hampering women's productivity? Studies say… Share on X

The study: Cognitive performance and temperature based sex differences

Researchers Tom Y. Chang and Agne Kajackaite (2019 study) found that, within an indoor temperature range of 16 to 33 degrees celsius, women perform better at the warmer end. Their study assessed 542 German students (41% female) with an avg. age of 24 years (median age 23 years) on 3 tasks testing 3 different aspects of cognitive performance: Verbal ability, Mathematical ability, and Cognitive reflection. In line with real-world demands on performance, researchers incentivized the tasks with reward money which was later converted into a final payoff at the end of the experiment.

To measure verbal ability, participants were tasked to create as many German words as they could from a string of 10 jumbled letters: “ADEHINRSTU”. Participants earned more money for longer words.

Researchers tested mathematical ability with a series of mental additions of 5 double-digit numbers (ex: 21 + 56 + 43 + 30 +75).

For cognitive reflection, they asked participants to answer 3 counter-intuitive logical questions (ex: “If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?”). Cognitive reflection is a test of one’s ability to override a wrong gut-feeling-based solution and rectify it with logical evaluation.

Women performed better than men on both verbal and mathematical ability tests at the warmer end but worse at the colder end. They attempted more problems and correctly solved more problems too. Men performed better on both at lower temperatures. At about 31-32 degrees celsius, men and women performed equally at the math test, but at 16 degrees, they performed worse than men. After 21 degrees, women’s verbal ability scores surpassed men’s scores. Researchers did not find any such temperature difference in their performance on the cognitive reflections task.

There are a few more nuances – the decrease in men’s math and verbal performance was less dramatic than the increase in women’s performance. For example, on the mathematical task, a 1-degree ambient temperature increase led to 1.76% higher correct-solves for women and only a 0.63% decrease in solve-rate for men. This particular trend has a practical insight for offices and standardized exam centers for SAT and GRE – the decrease in men’s performance is smaller in magnitude than women’s gain in performance. And by extension, moving closer to an ambient temperature preferred by women could lead to a collective gain in performance as opposed to a collective loss for men-friendly temperatures.

There are limitations to these changes in cognitive performance. While math and verbal tasks are affected by ambient temperature, cognitive reflection isn’t. Cognitive reflection^[4] tests a person’s ability to solve problems where the intuitive answer is different from the objectively correct answer. To successfully answer a cognitive reflection task, a person has to override a system 1 (quick gut-feeling) answer with a system 2 (logical) answer. Daniel Kahneman famously described system 1 as the cognitive system which relies on high-speed intuition, gut-feel, conditioning, and inherent biases while system 2 as a more careful, slow, and logically evaluated system.

A famous example of cognitive reflection is – “A bat and a ball cost 1 dollar 10 cents. The bat costs 1 dollar more than the ball. What is the cost of the ball?” Most people tend to quickly jump to the answer “10 cents.” But, the correct answer is 5 cents. 5 cents (ball) + 1 dollar & 5 cents (bat) equals 1.10 dollars. Most people get stuck on the intuitive answer of 10 cents because they compute the difference between the 2 givens – a bias where they ignore a system-level problem in favor of a component-level relationship. Such biases can reduce the validity of one’s interpretation & inferences based on the givens. Since biases tend to be rigid and habitual, superficial changes in temperature, which could affect cognitive resources, might not be potent enough to override them.

While the cognitive abilities of the sample were fairly homogenous, the study only looked at University students from Berlin. There is extensive diversity in work environments between job types, geographies, and economies. The current study extends the literature on gender differences across a spectrum of contexts and psychological variables such as violence, honesty altruism, and cooperation.

To really apply this finding in the real world, researchers would need to further address aspects of ambient temperature such as overall physical comfort, humidity, seasonal differences, baseline insulation of typical work clothing, etc.

Explanation and related research

The answer to why higher temperatures make women better at math and verbal tasks is unknown but there are a few explanations. One possibility is that overall comfort affects cognitive performance and warmer temperatures are more comfortable for women. An earlier study^[5] demonstrated a positive correlation between clothing comfort and exam scores: comfortable clothing was associated with higher scores in a statistics exam and uncomfortable clothing was associated with lower scores. They did this study in a naturalistic context like giving an actual exam and letting participants choose their clothing. In a study on 11 males^[6], cognitive performance was not affected by thermal and mechanical discomfort but the type of task affected perceived discomfort. Their perceived discomfort increased with easier tasks. This supports the idea that the loss in men’s cognitive performance is faint compared with the gain in women’s performance.

Professional dress codes should consider thermal comfort for all genders to maximize their productivity and satisfaction. Some clothing restrictions may be putting people at a cognitive disadvantage. Share on X

The interesting thing about this temperature-cognitive performance link is that, in the 2019 study, women reported more correct answers as well as more accurate answers at higher temperatures. The authors believe women answered more questions because they put in more effort. This increase in effort is, probably, facilitated by overall comfort. One interpretation of this temperature-cognition link is that women are willing to work harder than men at higher temperatures and effort mediates this relationship. While this study did not consider physical comfort as the main factor to study, there are rudimentary findings from other studies that support this conclusion.

Previous research^[7] shows that women prefer a slightly higher indoor temperature (by 1 to 3 degrees Celsius) than men and the 2019 study was consistent with this trend – women preferred higher temperatures than men. At around 32 degrees^[8] men and women both feel bored and drowsy and this relationship follows an inverted-U shape: Temperatures lower and higher than 32 degrees are linked with lower boredom and lower drowsiness. A 2018 review of studies^[9] found a mixture of significant and insignificant differences between men’s and women’s temperature preferences. So there may be a larger role of thermal comfort based on the choice of clothing, degree of control, ambient stress than pure averaged out preferences, especially for women. For example, women tend to value thermal comfort more^[10] than auditory comfort like background noise – the comfort generated by the right temperature and clothing may be more valuable than the discomfort of noise and that facilitates performance.

According to Sami Karjalainen^[11], it would be wiser to choose the ambient temperature (or thermostat settings) in favor of women because they will perform at their cognitive peak and a temperature chosen by females is most likely to be acceptable by males. Another key point here^[12] is that 80% of women’s acceptable range of temperature is 2 degrees narrower than that of males. So given this evidence, informed decisions about temperature controls should focus on meeting women’s needs.

The choice of room temperature in professional contexts should be in favor of women because their choice is likely to work for men but not vice versa, according to studies. Share on X

Newer research^[13] (2020) offers more insights into how sex differences in temperature choice play out – American men and women who live alone prefer the same temperature. However, more women lower the temperature before sleeping than men. This could mean that women are more sensitive to temperature differences and value temperature control.

Workplaces can be a source of major stress and dissatisfaction and that affects overall productivity. We know nature and natural elements affect employee well-being and productivity and many offices have chosen to implement “biophilia” to benefit employees. Similar strides can be made for an employee’s thermal comfort.

Research on the effect of temperature on cognition has important consequences such as designing and creating policies for gender-fair and inclusive workplaces and examination environments. Especially when gender biases exist in workplace environments and learning/testing environments.

A naive conclusion would be – “if you want a productive mixed-gender work culture, make sure you give enough control over the thermostat and make an informed trade-off: performance, preference, and overall gains against dislike and overall losses.” The ambient temperature may have an additive effect on cognitive performance in the workplace and academia, as well as on decision making in choosing a job.

Another area of application is air-conditioned transportation: Cabin temperatures for female pilots and bus temperatures for female drivers. Any environment which demands cognitive activity, effort, motivation, and working memory is a potential area of applying this research. By extension, low temperatures may compromise women’s productivity and a male-friendly temperature work environment might create an additional disadvantage for women.

It’s too premature to generalize these insights, but if you do want to fight over the room’s temperature, you can divert your attention to this body of research. One reason^[14] why it’s premature is that there seems to be an upper limit of indoor heat which is beyond thermal comfort for men and women that reduces productivity. Another reason is implementing a change in temperature. Should the temperature be fixed at a perfect balance where men and women are satisfied, productive, and cognitively sharp? If yes, there may be an indirect trade-off: Fixed temperatures, as opposed to variable temperatures, could have negative effects on long-term health as research suggests^[15] that variation in temperature can predict better health in the future.

So what’s the takeaway?

• Men perform better at low temperatures and women perform better at higher temperatures.
• As the temperatures increase, the gain in women’s performance is greater than the loss in men’s performance.
• Women are more sensitive to temperature changes and are more dissatisfied with cold environments.
• Too hot a temperature and people will assess themselves to be less productive than they would with a neutral temperature and that may be a source of dissatisfaction in work environments.

Proposed exploratory solutions for a gender-equal environment

• Give more control over temperature to women as men are likely to be satisfied with it without a loss in performance.
• Design environments that address the apparent drop in productivity for women at low temperatures before evaluating peak and low performance.
• Focus on adjusting the temperature to create a gender-friendly professional environment so women are more satisfied with the temperature.
• Allow more flexibility in professional attires and dress-codes so that women (and everyone else) can choose their optimal thermal comfort based on individual needs.
• Address women’s temperature needs before conducting studies and evaluations about sex differences in cognitive abilities and field performances.

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