What is different in the brains of serial killers such as Ted Bundy and Jeffrey Dahmer versus regular, "healthy" people?

I would recommend a Google search on the subject of brain scans of psychopaths, as you will see there are distinct differences.

In a nut shell, where the activity of a normal person’s brain demonstrates quite a bit of activity in the frontal and temporal regions when he/she experiences empathy, and little activity in the occipital region (the back back of the brain) where logical analysis occurs (which would indicate that empathy [and conscience for that matter] is an automatic visceral response for a normal person, and is not contrived or faked), the psychopath’s brain shows the exact opposite patterns.

Though your question references the brains of serial killers (bloody psychopaths), I think it is important to point out that “white collar” psychopaths are much more prevalent, yet their brains would essentially look the same under a color brain imaging scan. So, when I speak on the subject, I tend to focus more on this type of predator’s brain, as this predator is more dangerous, because he/she is much more self-controlled, and they have usually worked their way into the upper echelons of society.

So, whether we are talking about the brain of a bloody psychopath or a white collar psychopath, the issue in play is still a lack of activity where empathy and conscience are noted in “normal” people. The feelings of compassion, sorrow, and remorse in normal people are both genuine, automatic, and they fit the context or situation,and are experienced automatically.

So, the primary difference between the psychopaths brain and a “normal” person’s brain has to do with the brain’s ability to function any longer in terms of normal empathy and guilt. A normal person does not have to think about producing a proper empathic or apologetic response. A psychopath (who has lost the innate sense of compassion or empathy… and is without conscience) must study the person with whom they are interacting to ensure they “read the person” properly, in order to produce the expected response. Thus, the psychopath is adept at “working the crowd,” where as a normal person cannot turn their display of emotions on and off at will.

A classic example of this would be how Bill Clinton acted prior to knowing he was being filmed after walking out of Sec. of Commerce Ron Brown’s funeral, once he knew cameras were catching his actions. Watch how quickly he was able to go from laughing with his “spiritual advisor,” Tony Campolo, to acting in a way that would be expected of him... given that he had just left the funeral service.

This is how quickly a psychopath can “turn it on” and “turn it off” when he needs to for his own advantage.