The Human Brain Runs Way Hotter Than We Ever Realized, Scientists Find

When mechanical systems work harder, they tend to heat up. New research has shown that the brain runs hotter than was thought.

A new study shows that some parts of the deep brain can get up to 40 C. The average oral temperature in humans is under 37 C.

Researchers think that this isn't a sign that the brain is malfunctioning, but rather that it is. In the future, heat signatures could be used to look for brain damage.

Animation of brain temperatures over time. (N Rzechorzek/MRC LMB/Brain)

The most surprising finding from our study is that the healthy human brain can reach temperatures that would be diagnosed as a disease in other parts of the body.

It has been assumed that high temperatures have been measured in people with brain injuries.

Scientists used to measure brain temperatures from people with brain injuries, but that isn't the same as measuring the state of the brain during everyday life.

The team used MRS to measure brain temperature in healthy volunteers from 20 to 40 years old. They combined the information with the data on the time of day.

The brain temperature was more than 2 degrees higher than under the tongue. The time of day, the brain region, and the participant's age were all taken into account.

The highest brain temperature recorded was 40.9 C (108.6 C), which is most likely due to the menstrual cycle. The outer parts of the brain are cooler than the inner parts.

The brain temperature goes up and down during the day and night. We hope to investigate the link between daily variation and long-term brain health.

The researchers have been able to create a map of the brain. It can be used as a reference guide for what a healthy brain should look like, but more data is needed to make it useful.

The brain temperature of 114 people who had suffered a traumatic brain injury varied from 38.6 C to 42.3 C.

There is a correlation between brain temperature and the chance of surviving a traumatic brain injury.

Adding in another observation that brain temperature seems to increase with age, and it seems that regulating this temperature might be key to a healthy brain. Predicting the risk of future brain disorders is something that temperature rhythms could be used for.

"That a daily brain temperature rhythm correlate so strongly with survival after the traumatic brain injury suggests that round-the-clock brain temperature measurement holds great clinical value."

The research has appeared in a journal.