What do you mean?
It will change the test subject's mood, reactions and voice lines. However even if you boost it it will quickly revert to a 'default level'...and from what I can tell it's based on how clothed the subject is. RIP fans of Felicia's fur pattern and want her scared.
This has apparently been changed in the patreon locked updates, with a new status called sensitivity. So I guess things will be better in a year or so...