I contacted the author of the quoted example and this is the response I got (emphasis mine):
In this context it's supposed to be analogous to "guide" or "direct". The point of my argument being that antidepressants increase motivation for severely depressed. Unfortunately that motivation can be turned into negative activity, like attempting suicide or other forms of self harm, behaviors that earlier on was not enacted because the depression was so severe that there wasn't even enough motivation to go through with the suicide/self-harm, even if the self-loathing etc was even lower than it became after medication.
It's known in psychiatry that medicating severely depressed people, can cause an increase in suicide attempts. This is well documented. This is because there is now a little motivation, where earlier it was literally zero. That's why I said the motivation had to be "penced" towards healthy cognition and behavior.
They then followed up with a second message explaining where "pence" originated:
In my language "å pense" means to change the "switch" on a railroad track, so that when the train hits that fork, it will move to the left instead of right or vice versa.
So it was not a typo, but a mistranslation from a Germanic language, specifically Norwegian.