permanent monitoring “skullcap” implanted in the head. the technology is also far from perfect. It is not uncommon for soldiers like Shelley to become “emo-junkies”, becoming overly dependent on the processes of the skullcaps they wear. You can never be sure whether or not the emotions you feel are really yours, or if they are being controlled or altered by the skullnet. This question of “what’s real vs. what’s not” is a recurring theme that pops up throughout the novel, in many different contexts.