The movie American Psycho has helped us make the clear distinction between what’s normal and what’s downright crazy, cringe-inducing behavior. However, identifying a psychopath isn’t as transparent as Hollywood makes it out to be. Psychopathy, similar to height and weight, lies on a spectrum, which all of us — yes, including you — have a place on the continuum.

Being a psychopath doesn’t necessarily mean you’re going to go on a killing spree à la Christian Bale’s character Patrick Bateman, or that you will break the law. An antisocial/psychopathic personality is a disorder defined by the Diagnostic and Statistical Manual of Mental Disorders-5th Edition as a pervasive pattern of thinking/emotionality/behaving, and a personality disorder reflecting "adaptive failure" involving: "impaired sense of self-identity" or "failure to develop effective interpersonal functioning.” Moreover, antisocial/psychopathic types tend to have a charisma, impulsivity, and a pervasive pattern of taking advantage of people.

To help us see where we fall in the psychopathic spectrum, Kevin Dutton, psychologist and author of The Wisdom of Psychopaths: What Saints, Spies, and Serial Killers Can Teach Us About Success, presents the classic psychologist test known as "the trolley problem" with a variation. Dutton presents us with two life-saving scenarios to test and measure our response of the psychopathic spectrum. “[I]t may surprise you to know that there are some situations in which psychopaths are actually more adept at saving lives than they are at taking them,” he says in the video.

Dutton says: “Imagine you've got a train and it's hurtling down a track. In its path, five people are trapped on the line and cannot escape. Fortunately, you can flick a switch, which diverts the train down a fork in that track, away from those five people, but at a price. There is another person trapped down that fork and the train will kill them instead. Question: Should you flick the switch?”

Case one is what is known as an impersonal dilemma. It involves the areas of the brain such as the prefrontal cortex, the posterior parietal cortex, in particular, the anterior para singular cortex, the temporal pole and the superior temporal sulcus, which are primarily responsible for what is known as cold empathy, for reasoning and rational thought. Psychopaths, just like the rest of the normal population, will have no trouble flicking the switch so the train diverts accordingly.

The tables turn when Dutton presents case two. “You've got a train speeding out of control down a track and it's gonna plow into five people on the line. But this time you are standing behind a very large stranger on a footbridge above that track. The only way to save the people is to heave the stranger over. He will fall to a certain death, but his considerable bulk will block the train, saving five lives. Question: Should you flick the switch?”

Normal members of society will immediately express hesitation with case two as the emotion center of the brain — the amygdala and other brain circuits — will light up. However, in a psychopath’s mind, there would be no difference observed in brain activity going from the impersonal to personal case. Unlike normal people, psychopaths wouldn't blink and would chuck the fat guy over.

So how many lives would you save and would you take?