In Jojo's Bizzare Adventure, a specific character get the ability to allow him to accelerate the time of the world and himself to the point that he looks as though he is moving faster than a bullet (or basically the Flash). However, what I want to do is to make someone perceive time so slowly that everything around them is moving at superspeed (basically a debuff to grant the illusion of superspeed to everyone else or makes 10 minutes feel like a second). As for powers, my character has the ability to control all cells within any given body so long as the cells are in physical contact with each other. However, he can also infect people with those same cells to control/manipulate their bodies via chemical signals/pheromones. However, I don't have the full science down to how he can make people perceive time quickly, but I am sure that something can.
If you were to somehow delay the speed at which brain signals travel and are processed, that would cause the person to think slower and thereby percieve everything else as faster. Slowing down sensory inputs and motor-control outputs would probably fall under the same process, perhaps you could say that your superhuman causes the cells making up nerves to become "sluggish" or "unmotivated".
It should be noted that if this character is evil, they could pretty easily kill any person if they control the cells of the heart to not beat, or if they're a hero, it might be a struggle for them to slow down the nerves enough for a combat advantage but not so much that the opponent dies of... hypoxia, I think, or whatever category "signals to breathe not reaching your lungs for ~10 minutes" would fall under.