when someone is in a boat of sorts, and sees a island.
they descend into island insanity and have an uncontrollable urge to land on said island, and make camp there, or just run around and have a party.
ahhhh, I'm having island insanity!!... we must land there and make camp!
mountain madness is a form of madness that will come over a person when in the presents of mountains...they will seem to go insane, or "mad"...and have an uncontrollable urge to climb said mountain at an ungodly pace, and with no concern for self preservation of any sort.
omg joe, we have to climb that mountain!!!,
sick with mountain madness, the two intrepid adventurers toil onward to the summit
when on a long hike, and the summit (or awesome view) is near and within reach, one will go into "rampage mode"... a mode of rampage where one will use up all of his/her energy in a last ditch effort to reach the summit as soon as possible and at a mad pace.
oh my, he has gone into rampage mode again... i hope he will have energy to make it off the mountain before dark.