What part of the brain would have to be destroyed to cause immediate death?
Not the brain, the top bit of the spinal cord called the brain stem. That regulates all of your necessary autonomous functions like breathing and heart beats. You’d still be alive for a few seconds, so I guess it wouldn’t be immediate. Destroying one part of the brain won’t kill you (at least not nearly as fast as what I described above). The brain is mostly associated with processing sensory data, making decisions and thoughts, sending nerve impulses to muscles, and regulating the endocrine system. The basic vital functions are controlled by the spine. Brain damage turns you into a vegetable, spinal damage kills you.
