What is trepanation? and why was this used?

Trepanation is the process whereby a hole is drilled into the human skull, exposing the dura mater to treat health problems related to the intracranial disease of the human body.

Explanation:

Trepanation is used to treat health problems associated with intracranial diseases, epileptic seizures, migraines and mental disorders by relieving pressure.

answer; atp and nadph;