John Nash, the Nobel-winning economist from Princeton, portrayed in "A Beautiful Mind," could be brilliant in his field, even as he suffered from schizophrenia.
Psychotics like Seung-Hui Cho, the student who killed 31 at Virginia Tech in 2007, are particularly dangerous.
They view others as inconsequential and often humiliation can set off a psychotic depression that could make a person violent or suicidal, said Galynker.
Madison County District Attorney Robert Broussard, who will prosecute the case against Bishop, said he would not oppose a mental evaluation.
Bishop's only public comments since the killings have been, they "didn't happen. There's no way," as police led he away after the massacre. "There's no way. They're still alive."
Both Bishop and her husband Anderson have been described by "oddballs" but neighbors and colleagues in both Boston and in Alabama.
Anderson has been talking to media outlets across the country, downplaying his wife's past outbursts.
He has said faculty sabotaged his wife's aspirations for tenure, sending "nastygrams," and that she may have even been the target of a stalker.
"I don't buy that," said Tom Capozzoli, an associate professor of psychology at Purdue University and an expert in workplace violence.
He speculated the shooting was "well-planned," and impulse control disorder may have played a role. But he wonders about Anderson, as well.
"I'd be very curious about his mental stability," Capozzoli said. "I seriously can't believe that he didn't know that something was going on.
"There were lot of trigger events," Capozzoli added, "and if he knew what to look for, he might have prevented it."
In an interview this week, Anderson deflected questions about Bishop shooting her 18-year-old brother, her being interviewed by police over a mail bomb sent to a professor at Harvard University and even the punching of a woman at an International House of Pancakes over a booster seat.
When asked if his wife had mental problems, Anderson told ABCNews.com, "I know what's inside the brain, I don't know how it works."
"Part of me is a scientist and I can't do anything until I get all the data in," he said.
Of the revelation that his wife hit a restaurant customer in the head in 2002, Anderson said, "Another patron started it and tried to blow it out of proportion. When someone jumps in your business, in your face, you get upset."
A judge disagreed, sentencing Bishop to probation as prosecutors recommended she take anger management classes, according to a report in the Boston Globe.
He backed up his wife's claim that the 1986 death of her brother Seth Bishop was "accidental," even as new reports revealed that in the hours after the shooting she still carried the shotgun when confronted by police at a nearby Ford dealership.
"She's like, 'Hands up!' and I'm like, 'Yes ma'am,'" auto body worker Tom Pettigrew told the Boston Herald.
Of the reports that he and his wife were questioned in 1993 when one of Bishop's colleagues, Harvard University's Dr. Paul Rosenberg, received a pipe bomb in the mail, Anderson said, "We were cleared of that."
Neighbors' claims in both Massachusetts and Alabama that the couple was belligerent and confrontational were laughed off by Anderson.
"They were out of line saying Amy was nuts and I realized they had accused her of using a ray gun to stop kids from operating their motorcycles," he said of their Huntsville neighbors.