I did, though, want to run this excerpt from WebMD. I think there's some interesting points made.

Mental Illness, Antidepressants, and Violence

Could the antidepressants that Cho was said to have been taking made him violent? No, [Robert] Irvin, MD, [medical director of a long-term residential treatment program that is part of the Bipolar and Psychotic Disorders Program at Harvard's McLean Hospital in Belmont, Mass] says.

It's not known whether Cho was taking antidepressants under a doctor's supervision, whether he was taking the medications properly, and whether he was taking some drug other than antidepressants.

"Certainly just being on an antidepressant does not increase your risk of engaging in violence," Irvin says. "Antidepressants causing increased risk of self-harm have been talked about, but there is much more evidence to support that they are effective in treating depression. The risk of self-harm is much greater when patients are left untreated."

Might underlying depression be to blame? Probably not.

"People who are hopeless, who don't experience any joy or happiness, their thoughts are far more likely to tend toward self-harm than harm to anyone else," Irvin says. "If they are moved to violence, they are far and away more frequently the victims."

There is a form of depression -- some think it a form of psychosis -- which doctors call "major depression with psychotic features." People with this kind of depression have delusional thinking -- such as believing everybody at their workplace is very clearly out to get them, perhaps by putting bugs in their offices in order to control them.

"If you are paranoid, perceiving you are threatened when you are not, you might be prone to violence," Irvin says. "But these are people who, if given a choice, would hurt themselves or flee before acting in an aggressive way toward others."

Victoroff agrees that paranoid individuals are more prone than others to commit violence.

"Someone who has a grossly distorted threat-perception system is more likely to commit violent acts," he says. "Humans respond to threat by flight or by fight. Those predisposed to respond with fight, who regard innocent people all around them as terribly threatening to them, will be prone to harm those innocent people."

Even so, Victoroff says, the majority of people suffering paranoia do not commit violent acts, so it's impossible to say whether a particular paranoid man or woman will become violent.

We tend to think that only mentally ill people would commit horrific crimes. But this may be false reassurance, Irvin says.

"One of the reasons we try to understand this aberrant behavior in terms of an illness is that it gives us a sense we can identify these people ahead of time. But just because the act is crazy does not mean the person suffered from a defined psychiatric illness," he says. "It is an ongoing debate whether these people need to be dealt with in the criminal justice system or the mental health system."

That's because there are two basic forms of violence: sudden, impulsive acts of aggression and premeditated violent acts.

"Premeditated aggression enters the realm of pathologic sociopathy -- and there is no good known treatment for sociopaths," Irvin says.

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