I wonder if the fiducia compellia spell works in a manner somewhat similar to the extinguishing stele but with a milder effect and with reversibility. If so then the spell works simply by reducing the subject’s level of consciousness, making them more suggestible and reducing or inhibiting certain abilities that are given by consciousness, such as independent thought and decision making, abstract thought, and executive function, regardless I’m sure the suppresses activity in the prefrontal cortex in some manner