the visual impairment caused by playing too much Guitar Hero, DJ Hero, Band Hero, or Rock Band that makes it seem like the background and foreground are melting while the middle-ground stays still.
this symptom nearly always falls in conjunction with, but is not exclusively tied too any of the following: dizziness, Carpel Tunnel Syndrome, loss of friends, loneliness, virginity, false feelings of self accomplishment, pretending to know how to pretend to play the guitar, turntables, drums, etc.. excessive use of air-drums, air-guitar, amateurish beat boxing, and or scratching motions with one's middle and forefingers.
if someone you know is experiencing activision, DON'T PANIC!! chances are they are not your friend anyway and it is recommended that a doctor be consulted before realizing that there isn't shit you can do about it short of mercilessly, but lovingly beating them with their own plastic instruments. this will cure the activision, and leave you feeling satisfied and relieved.
inflicted: "woah... the room looks like its melting"
person: "that's called activision. it happened because youve been in a dark room for 5 hours trying to beat "through the fire and the flames" on expert and didnt stop to give your eyes a rest"