Though these people seem like emotional opposites, their brains show one similarity: the amygdala, a center for emotional response to stimuli, and the ventromedial prefrontal cortex (or vmPFC), which processes negative emotions' effects on mood and anxiety, have less functional connectivity than a person without anxiety or mood disorders. The research behind this, such as Dr. Koenigs', note that the connection between centers like the amygdala and the vmPFC are bidirectional, which likely explains why this connection is similarly impaired - though an anxious person may have a more functional amygdala than a psychopath, the connection to the emotional processing centers (such as the vmPFC) may be similarly impaired in both individuals.
Dr. Koenigs has done research on the connection between the amygdala and the vmPFC by doing MRIs on many prisoners categorized as psychopathic through a psychological exam and interviewing veterans who had experienced injuries to their vmPFC. The veterans who had injuries to their vmPFC had lower rates of post-traumatic stress disorder (PTSD) as compared to veterans who had not sustained injuries to this part of their brains, which was parallel to psychopaths who show low levels of PTSD due to a reduced connection to their vmPFCs.
To examine the brain and psychopathy, the New York Times examined callous-unemotional (CU) children and concluded that because of lower levels of cortisol and decreased function in the amygdala, even children as young as nine years of age could be categorized as psychopaths, because psychopathy originates in the brain. The children showed behaviors such as impulsivity, aggression, manipulativeness and defiance, all characteristics that point to impaired vmPFC and amygdala connection. The amygdala also produces emotions such as fear and shame, which the CU children lacked.
Time Magazine further investigated the origins of psychopathy in the brain by contrasting psychopath's brains with those of people with disorders such as anti-social personality disorder (ASPD). Though both were more likely to make violent decisions, the psychopaths showed almost no anxiety, PTSD, or fear surrounding their violent actions in comparison to the ASPD individuals who often showed PTSD or guilt following such actions. Not surprisingly, the psychopaths showed less volume in certain parts of their pre-frontal cortex (including the vmPFC) in comparison to the ASPD individuals.
It is clear that psychopaths have an impaired connection between their emotional centers of the brain and the prefrontal cortex that processes the emotions because they have less emotional output to those centers, but what about individuals with anxiety?
Science Direct found that the vmPFC, in a normally-functioning brain, minimize the effect of anxiety and threats on performance in a video game. It is likely that in individuals with anxiety, the vmPFC's reduced connectivity to the amygdala causes threats and stress to impair the individual's normal function, which helps to explain why both psychopaths and people with anxiety disorders have reduced vmPFC and amygdala connectivity.
All in all, research like this shows that to understand neuroscience and our brains more adequately we cannot only examine its centers - many of the answers to the diseases and mental disorders that impair people lie in the connectivity and communication between specific centers of the brain. Externally, people with anxiety disorders and psychopaths seem very different - yet this particular connection in their brains is similarly impaired. Clearly, there are many mysteries are hidden within the intricate web of each and every person's brain that science has yet to work to understand.
Works Cited
1. http://www.nytimes.com/2012/05/13/magazine/can-you-call-a-9-year-old-a-psychopath.html
2. http://healthland.time.com/2012/05/14/understanding-the-psychopathic-mind/
3. http://www.sciencedirect.com/science/article/pii/S0006322314002650
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