From the 80s cartoon, the episode "Nightmare Assault". Dr. Mindbender has invented a machine that allows him to give the Joes nightmares to (a) disrupt their sleep and make them less effective in the field; and (b) create opportunities to Mind Screw them by re-creating nightmare imagery in the real world. Then he turns the machine on Low-Light, who's already prone to nightmares (unresolved father issues, it seems). Turns out, the machine's nightmares are so weak compared to Low-Light's standard fare that he's not only able to overcome the device and help his teammates do likewise, but he actually makes progress with his own nocturnal terrors.
Low-Light: You gotta be tougher than that. I'm not a wimp anymore! I'm a G.I.Joe - and nothing stops a G.I. Joe! NOTHING!!
- To top it off, he makes sure Mindbender gets Hoist by His Own Petard when in the process, Low-Light ends up giving the Doctor such a scare through the machine that Mindbender destroys it, having seen this was too much even for him.