Here’s a new interesting new paper on the emotional deficits of the psychopathic brain, via sarcastic_f:
The understanding that other people’s emotional states depend on the fulfilment of their intention is fundamentally important for responding adequately to others. Psychopathic patients show severe deficits in responding adequately to other people’s emotion. The present study explored whether these impairments are associated with deficits in the ability to infer others’ emotional states. Using functional magnetic resonance imaging (fMRI), identical cartoon stories, depicting a subject whose intention was fulfilled or not fulfilled, were presented to 14 psychopathic patients and 14 non-psychopathic patients. The participants should indicate the protagonist’s emotional state…In non-psychopathic patients emotion attribution was associated with increased activity of the mirror neuron system, the bilateral supramarginal gyrus and the superior frontal gyrus. In contrast psychopathic patients showed increased activation of regions associated with outcome monitoring and attention, such as the orbitofrontal cortex, the medial frontal cortex and temporo-parietal areas. The results emphasize that although psychopathic patients show no deficits in reasoning about other people’s emotion if an explicit evaluation is demanded, they use divergent neural processing strategies that are related to more rational, outcome-oriented processes.
On a related note, the Templeton Foundation recently asked me, and a bunch of much more qualified people, to answer the following grandiose question: “Does moral action depend upon reasoning?” Here’s part of my answer:
Psychopaths can teach us a lot about the nature of morality. At first glance, they seem to have perfectly functioning minds. Their working memory isn’t impaired, they have excellent language skills, and they don’t have reduced attention spans. In fact, a few studies have found that psychopaths have above-average IQs and reasoning abilities; their logic is impeccable. But the disorder is associated with a severe moral deficit.
So what’s gone wrong? Why are psychopaths so much more likely to use violence to achieve their goals? Why are they so overrepresented in our prisons? The answer turns us to the anatomy of morality in the mind. That’s because the intact intelligence of psychopaths conceals a devastating problem: the emotional parts of their brains are damaged, and this is what makes them dangerous.
When normal people are shown staged videos of strangers being subjected to a powerful electrical shock or other painful stimulus, they automatically generate a visceral emotional reaction. Their hands start to sweat, and their blood pressure surges. But psychopaths feel nothing. It’s as if they were watching a blank screen. Most people react differently to emotionally charged verbs like kill or rape than to neutral words like sit or walk, but not psychopaths. The words all seem equivalent. When criminologists looked at the most violent wife batterers, they discovered that, as the men became more and more aggressive, their blood pressure and pulse actually dropped. The acts of violence had a calming effect.
When you peer inside the psychopathic brain, you can literally see this absence of emotion. After being exposed to fearful facial expressions, the emotional parts of the normal human brain show increased levels of activation. So do the cortical areas responsible for recognizing faces. As a result, a frightened face becomes a frightening sight; we naturally internalize the feelings of others. The brains of psychopaths, however, respond to these fearful faces with utter disinterest. Their emotional areas are unperturbed, and their facial recognition system is even less interested in fearful faces than in perfectly blank stares. Their brains are bored by expressions of terror.
Neuroscientists are beginning to identify the specific deficits that define the psychopathic brain. The main problem seems to be a broken amygdala, a brain area responsible for secreting aversive emotions, like fear and anxiety. As a result, psychopaths never feel bad when they make other people feel bad. Aggression doesn’t make them nervous. Terror isn’t terrifying. (Brain imaging studies have demonstrated that the amygdala is activated when most people even think about committing a “moral transgression.”)
This emotional void means that psychopaths never learn from their adverse experiences: They are four times as likely as other prisoners to commit another crime after being released. For a psychopath on parole, there is nothing inherently wrong with violence. Hurting someone else is just another way of getting what they want, a perfectly reasonable way to satisfy their desires. In other words, it is the absence of emotion–and not a lack of rationality–that makes the most basic moral concepts incomprehensible to them.
Needless to say, this is a disquieting idea. We like to pretend that human morality rests upon a more solid foundation that our Pleistocene instincts, or our deep past as a social primate. Kant, for instance, famously believed that our morality was based on objective, universal values; moral judgments described moral facts. “The oftener and more steadily we reflect” on our moral decisions, Kant suggested, the more moral those decisions become. The modern legal system still subscribes to these assumptions and pardons anybody who demonstrates a “defect in rationality” (such people are declared “legally insane”), since the rational brain is supposedly responsible for distinguishing between right and wrong. If you can’t reason, then you shouldn’t be punished.
But psychopaths and various trolley experiments are giving us new insight into the emotional mess of moral decision-making. This doesn’t mean, of course, that reason is irrelevant. If history has taught us anything, it’s that social norms – the explicit and implicit rules governing what’s morally acceptable – are deeply plastic. These changes don’t happen fast – the arc of the moral universe is long – but they do tend towards greater justice. This isn’t because we’ve evolved a new set of moral emotions, or because we’ve suddenly learned to appreciate Kant’s categorical imperative. Rather, it’s a reflection of the fact that we now apply our empathetic mental muscles – what Adam Smith called “fellow-feeling” – to a much wider range of people. In other words, the invention of Promethean reason (via the PFC) didn’t mean that our moral emotions got superseded. Instead, it means they’ve been busier than ever, as we now apply our moral emotions not just to people who look like us, or are part of our tiny tribe, or share our sexual preferences. The optimistic trend of history is towards a world in which everyone is deserving of our sympathy.