When you’ve pressed a cold towel to your head or neck on a hot day,
“my head feels clearer,”
“that foggy feeling has eased,”
have you ever felt this way?
In summer, many people find that it isn’t only their body that suffers; they also feel that their “brain just isn’t working” or that they “can’t concentrate.”
In fact, research is beginning to show that heat is linked to how our brains function.
This time, drawing on research data, we look at why heat makes our heads feel foggy and why cooling the head and neck feels so refreshing.
Is It True That Too Much Heat Makes Your “Brain Stop Working”?
Our bodies are equipped with thermoregulation, a system that keeps body temperature within a certain range.
When it gets hot, we sweat and increase blood flow to the skin to release the heat that has built up in the body.
However, when intense heat continues and the heat load on the body grows, it may affect not only the body but also cognitive functions such as attention, judgment and memory.
A 2002 meta-analysis by researchers at Clemson University in the United States, which analyzed 515 effect sizes calculated from 22 studies, showed that performance on cognitive and other tasks declines in both hot and cold environments.
In particular, under hot conditions of about 32.2°C (90°F) or above, performance dropped by an average of 14.88% compared with a neutral-temperature environment.
Of course, the effects vary depending on temperature, humidity, length of exposure, the task being performed and so on.
Even so, there is a scientific explanation behind the feeling that “my brain doesn’t work as well as usual on hot days.”
Why Does Cooling Your Head and Neck Feel Refreshing?
So does cooling your head directly lower the “temperature of your brain”?
Here we need to be a little careful.
Cooling your scalp or neck does not mean the temperature of the brain itself drops sharply.
On the other hand, the head, face and neck are areas that are especially sensitive to cold, and cooling them locally is known to ease the feeling of being “hot” and “uncomfortable.”
In 2025, researchers from Southern Cross University and Queensland University of Technology in Australia, the University of Roehampton in the UK and other institutions published a systematic review and meta-analysis covering 63 studies and 618 participants.
The results confirmed that cooling the head, face and neck lowers skin temperature in the cooled areas and improves how hot people feel and how comfortable they are.
In other words, the “feels great” and “refreshing” sensation you get from pressing a cold towel to your head or neck is likely not just your imagination.
“Feeling Refreshed” Does Not Mean “Better Brain Function”
This is another important point.
In the 2025 meta-analysis mentioned above, there was not enough research data on the effects of cooling the head, face and neck on cognitive function to pool it in a combined analysis.
There is also a study in which cooling the head and neck in a hot environment reduced heat-related fatigue, but no change was seen in cognitive function itself.
That’s why simply thinking
“cool your head → your brain cools down → your brain works better”
is not accurate.
For now, it’s more appropriate to think that cooling your head and neck eases the heat and discomfort, and as a result, you’re more likely to feel refreshed.
More Cooling Isn’t Always Better
Cooling off feels good when it’s hot, but for the body, “the colder the better” is not true.
In a 2021 systematic review of 18 studies by researchers at the University of Trento in Italy and other institutions, 15 of the 18 studies on exposure to severe cold found a decline in cognitive performance. Attention, information processing speed, executive function and memory were especially affected.
What matters is not cooling the body to extremes, but moderately easing the strain caused by heat.
If the Heat Leaves You Foggy, Don’t Forget to Hydrate
Cooling your head is one way to relieve the heat, but on its own it can’t prevent heatstroke.
On hot days, it’s important to protect your whole body from the heat: move to a cool place, replenish fluids and electrolytes as needed, and rest rather than pushing yourself.
In particular, if you have symptoms such as
“a headache,”
“dizziness,”
“nausea,”
“strong fatigue,”
don’t dismiss them as simple “mental fatigue”; be aware that they could be signs of heatstroke.
In Shinjuku, a Place to Rest a Head and Body Worn Out by the Heat
La HEAD is a head massage and dry head spa salon with fully private rooms, a 3-minute walk from Shinjuku-nishiguchi Station.
In summer, we go back and forth between the hot outdoors and air-conditioned rooms again and again, so many people feel that their “head is somehow heavy” or their “body is tired.”
At La HEAD, we care for not only your head but also your neck, shoulders and arms as one connected whole, and we value letting you relax at your own pace in a calm, fully private room.
On days when the heat leaves even your mind feeling tired, why not not only cool your body but also make time to rest slowly without thinking about anything?
We look forward to welcoming you.