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After studying the brains of violent killers, rapists and robbers, German neurologist Gerhard Roth claims to have found a “dark patch” in the center of the brain -- he calls it the evil spot, a genetic source of violent behavior.

Roth, a professor at the University of Bremen, told Germany news site Bild.de that he had shown short films to criminals and measured their brain activity. A small section at the front of their brains showed no reaction to violent scenes; it remained "dark" when shown dark scenes.

"Whenever there were brutal and squalid scenes, the subjects showed no emotions. In the areas of the brain where we create compassion and sorrow, nothing happened,” Roth said.

BioEdge, a blog dedicated to bioethics news, translated Roth's German into English: “This is definitely the region of the brain where evil is formed and where it lurks.”

Not so fast. Human behavior, affect and emotion is likely a far more intricate thing, explained Dr. Steven Galetta, chairman of the neurology department at the NYU School of Medicine.

'It’s probably not as simple as X marks the spot for a particular behavior.'

— Dr. Steven Galetta, chairman of the neurology department at the NYU School of Medicine

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“People look at the blood flow to one area and they say, ‘aha, this is the evil patch.’ It’s probably a lot more complex than that,” Galetta told FoxNews.com.

“Certain areas are likely important for certain behaviors, certain attitudes. But it’s probably not as simple as X marks the spot for a particular behavior.”

Roth’s study, according to Bild.de, was conducted for the German government on violent convicted offenders. He said the dark mass that he has identified appears in all CT scans of people with such records -- and taking it out ended their “evil” behavior.

Roth did not respond to FoxNews.com requests for more details on his study.

Terre Constantine, executive director of the Brain Research Foundation and the former director of the Jack Miller Center for Peripheral Neuropathy, expressed skepticism at the report, but agreed that brain abnormalities such as tumors can affect behavior.

“It absolutely can affect the brain and your personality and how you communicate. And it can make you aggressive -- not all tumors, of course: it depends where it is,” Constantine told FoxNews.com.

Her foundation, which funds research into neuroscience seeking to understand the brain’s workings, has aided research similar to Roth's with more advanced imaging techniques.

One recent study from a University of Chicago researcher studied parenting behavior. It found activity in the amygdala -- a portion of the brain connected to the limbic system -- correlated to parenting style. It “lit up” in the brains of normal mothers, while “harsh parents” didn’t react to scenes of bad parenting.

“There’s clearly differences in the brain depending on what sort of disease or abnormality a person has,” she told FoxNews.com. And many things can cause abnormal behaviors. “They’re either wired differently or there might be some disease that’s causing the brain to atrophy.”

But Constantine agreed with Galetta: Complex topics and behaviors are likely linked to other areas of the brain, rather than concentrated in one “evil area.”

“I would argue it’s probably not the only “evil” spot,” she said. “There are other areas in the brain, there are lots of … empathy areas or violent areas or just social reaction areas within the brain.”

“This may be one of the spots, but I’d be surprised if it’s the spot.”