Brothers having a slight disagreement Aggression in cats is not uncommon, but it's unusual for it to be serious enough for people to seek professional help. Just a decade ago, however, a study from Cornell University noted an upward trend in people-directed aggression. Those researchers thought it may be attributable to an increasing tendency to keep cats inside the home (and thus interacting more with people). Other possible explanations: cats are actually getting more aggressive (a bad thing), or people are becoming more aware that feline behavior problems are amenable to treatment (a ...