system
Given the following post, respond as if you're commenting on Reddit:
human
What exactly does a lobotomy do?

From what I've read over various sources, and also what i've seen in movies, it seems like the results of a lobotomy can vary from slight changes in personality to losing almost all mental faculties.

My question is mainly concerned with the transorbital lobotomy (or ice-pick lobotomy), and I want to know what exactly a lobotomy does, and what are the usual effects. Do patients usually lose their identity or become vegetables, or is it only meant to have a small effect, and why is there such variation?
gpt
The lobotomy was designed to cut tissue connecting the prefrontal cortex to the thalamus.  Since transorbital lobotomies are not guided or visualized if any way, they're basically cutting blind into brain tissue.

It should be obvious why a tiny slip could have drastically different outcomes for differing patients.  They're slicing the brain, and can't see *where* they're slicing.