How high above normal temperature does the brain have to heat up before cells start cooking? (In degrees)?

Catty (source: National Geographic Society)

Fever in itself can be harmful, but only if the temperature hits 107 degrees, which is uncommon. The body's protective mechanism usually halts it at 106.

Source: Boston Globe Magazine

According to the Nat'l Geographic Society, the temperature of the brain has only to rise 2 degrees above normal to start cooking the cells.

Catty (whose brain cells were cooked a long time ago)

Wow! That's pretty low for damage to be done. Thanks for sharing, Catty.

My dad had a fever of 106 once, and he lost his ability to feel drunk. He said that takes all the fun out of it!

Many parents fear that fevers will cause brain damage. Brain damage from a fever generally will not occur unless the fever is over 107.6°F (42°C). Many parents also fear that untreated fevers will keep going higher and higher. Untreated fevers caused by infection will seldom go over 105°F unless the child is overdressed, or trapped in a hot place. - MedlinePlus

MedlinePlus brings together authoritative information from NLM, the National Institutes of Health (NIH), and other government agencies and health-related organizations.
----
Home Care (Read "Call Your Doctor…" first):
Reassurance

Presence of a fever means your child has an infection, usually caused by a virus. Most fevers are good for children and help the body fight infection.

Use the following definitions to help put your child's level of fever into perspective:

* 100-102°F (37.8-39°C): low grade fever and beneficial, desirable range
* 102-104°F (39-40°C): moderate fever, still beneficial
* > 104°F (40°C): moderately high fever and causes discomfort, but harmless
* > 105°F (40.6°C): high fever - higher risk of bacterial infections (3% risk)
* > 106°F (41.1°C): very high fever - important to bring it down
* > 107°F (41.7°C): dangerous fever - the fever itself can be harmful to the brain
Source: http://www.seattlechildrens.org/child_health_safety/health_advice/fever.asp
--------
In my readings, sometime in the 1990s, I found that health experts were revising previous ideas about fever, and that humans could tolerate higher temperatures than previously thought without sustaining brain damage.