The Better Angels of Our Nature: Why Vio - By Steven Pinker Page 0,306

found that when a person feels he is getting a raw deal from another person who is dividing a windfall between them, the insula is fired up. When the stingy allocation is thought to come from a computer, so there’s no one to get mad at, the insula remains dark.62

The orbital cortex resting on the eyeballs (figure 8–3) and the ventromedial cortex facing inward (figure 8–4) are, as mentioned, adjacent, and it’s not easy to distinguish what they do, which is why neuroscientists often lump them together. The orbital cortex seems to be more involved with determining whether an experience is pleasant or unpleasant (befitting its position next to the insula, with its input from the viscera), while the ventromedial cortex is more involved with determining whether you are getting what you want and avoiding what you don’t want (befitting its position along the midline of the brain, where the Seeking circuit extends).63 The distinction may carry over to a difference in the moral realm between an emotional reaction to a harm, and judgment and reflection on it. But the dividing line is fuzzy, and I’ll continue to use “orbital” to refer to both parts of the brain.

The inputs to the orbital cortex—gut feelings, objects of desire, and emotional impulses, together with sensations and memories from other parts of the cortex—allow it to serve as the regulator of emotional life. Visceral feelings of anger, warmth, fear, and disgust are combined with the person’s goals, and modulating signals are computed and sent back down to the emotional structures from which they originated. Signals are also sent upward to regions of the cortex that carry out cool deliberation and executive control.

This flowchart suggested by the neuroanatomy corresponds fairly well with what psychologists see in the clinic and lab. Making allowances for the difference between the flowery language of medical reports in the 19th century and the clinical jargon of the 21st, today’s descriptions of patients with damage to their orbital cortex could have applied to Phineas Gage: “Disinhibited, socially inappropriate, susceptible to misinterpreting others’ moods, impulsive, unconcerned with the consequences of their actions, irresponsible in everyday life, lacking in insight into the seriousness of their condition, and prone to weak initiative.”64

The psychologists Angela Scarpa and Adrian Raine offer a similar list, but with an additional symptom at the end that is relevant to our discussion: “Argumentativeness, lack of concern for consequences of behavior, loss of social graces, impulsivity, distractibility, shallowness, lability, violence.”65 The extra noun came from Raine’s own studies, which, instead of selecting patients with orbital brain damage and then examining their personalities, selected people prone to violence and then examined their brains. He focused on people with antisocial personality disorder, defined by the American Psychiatric Association as “a pervasive pattern of disregard for, and violation of, the rights of others,” including lawbreaking, deceit, aggressiveness, recklessness, and lack of remorse. People with antisocial personality disorder make up a large proportion of violent felons, and a subset of them, who possess glibness, narcissism, grandiosity, and a superficial charm, are called psychopaths (or sometimes sociopaths). Raine scanned the brains of violence-prone people with antisocial personality disorder and found that the orbital regions were shrunken and less metabolically active, as were other parts of the emotional brain, including the amygdala.66 In one experiment, Raine compared the brains of prisoners who had committed an impulsive murder with those who had killed with premeditation. Only the impulsive murderers showed a malfunction in their orbital cortex, suggesting that the self-control implemented by this part of the brain is a major inhibitor of violence.

But another part of its job description may come into play as well. Monkeys with lesions in the orbital cortex have trouble fitting into dominance hierarchies, and they get into more fights.67 Not coincidentally, humans with orbital damage are insensitive to social faux pas. When they hear a story about a woman who inadvertently disparaged a gift she received from a friend, or accidentally divulged that the friend had been excluded from a party list, the patients fail to recognize that anyone had said anything wrong, and don’t realize that the friend might have been hurt.68 Raine found that when people with antisocial personality disorder were asked to compose and deliver a speech about their own faults, which for ordinary people is a nerve-racking ordeal accompanied by embarrassment, shame, and guilt, their nervous systems were unresponsive.69

The orbital cortex, then (together with its ventromedial neighbor), is involved in several of the pacifying faculties of the human