—
The soft tissue of the brain is the starting point for everything we do.
What is allowing you to perceive the words of this sentence, understand their meaning, remember the contents of the previous section, feel the pages or device you hold in your hands, and decide to continue on to the next paragraph?
The answer is nothing more than neurons, synapses, and neurotransmitters. Take away these electrochemical interactions and that’s it: no thoughts, no emotions, no choices, no behavior.
Even for those with no religious inclination, it doesn’t feel that way. It feels as if we have something like a “soul”—independent, purposeful, and rational—directing our actions. How could that thing be nothing more than neurons generating electrical impulses, triggering chemical signals carried to other neurons? It seems improbable, impossible even. But that is the truth.
There wasn’t some villainous spirit commanding Masters to assault that eight-year-old girl; his behavior arose from the three-pound lump of cells nested in his skull. A useful starting point in deciphering the causes of criminal behavior, then, is to consider how the brain of a criminal like Masters might differ from a “normal” brain.
Even back in Masters’s time, there was some appreciation of the fact that particular areas of the brain might be involved in regulating particular behaviors. Perhaps the most famous example was that of a twenty-five-year-old supervisor for the Rutland and Burlington Railroad in Vermont, Phineas P. Gage.
Gage’s fame all came down to a tragic and miraculous event one day in 1848, when he decided to pack explosive powder into a rock using a metal rod. His actions (perhaps not unexpectedly, to our cautious modern eyes) triggered a sudden explosion, and the thirteen-pound piece of iron was driven up through his left cheek and straight out of the top of his head.
In an amazing bit of luck, despite horrible damage to his prefrontal cortex and other areas of his brain, Gage survived with most of his physical and intellectual capacities preserved. But as his friends quickly noticed, Gage was “no longer Gage.” Respectful, pleasant, and dutiful before the accident, Gage became lazy, boorish, and foul-tempered. The injury to particular parts of his brain seemed to change particular aspects of his behavior.
But there is no evidence that Gage ever engaged in truly criminal behavior, and perhaps a more relevant case to Masters’s is one reported in the Archives of Neurology more than 150 years after Gage suffered his injury. Indeed, many of the facts seem to echo the reports on Masters.
In 2000, a married forty-year-old Virginia schoolteacher, Mr. Oft, who had never had abnormal sexual urges, suddenly began collecting child pornography and, soon thereafter, attempted to molest his prepubescent stepdaughter. As a first-time offender, the man was diverted to a twelve-step inpatient program for treatment of his sexual addiction. Any serious slip-up and he would be sent to prison. Even though he understood that risk, did not want to be incarcerated, and seemed to know that what he was doing was wrong, he began to solicit sex from the staff at the rehabilitation facility.
Oft was kicked out of the program, of course, and was set to be sentenced the next day, when he developed an intense headache. It was so bad that he had to go to the hospital. But no sooner had his neurological examination begun than he was propositioning the women in the room and openly discussing his fear that he would rape his landlady.
With his bad behavior in clear evidence, the doctors might have written off the headache as a mere ruse to delay going to prison, but instead they ordered a brain scan. What they found was staggering: a tumor, as big as an egg, in the right orbitofrontal area.
The surgery to remove it provided similarly stunning results: with the tumor excised, Oft lost all interest in pornography and easily completed the Sexaholics Anonymous program that had previously been such a struggle. Seven months later, he was permitted to return home.
Oft’s apparent recovery, however, did not last. By October 2001, his headache had reappeared—as had his secret collection of explicit materials. Were the two again connected? Sure enough, when doctors ordered another brain scan, they found that the tumor had grown back. And with a second surgery, in February 2002, the sexual deviance vanished once again.
Cases like these provide vivid illustrations of how deficits in the brain can produce profound changes in behavior. But it is important to understand that such clear examples are rare, and anecdotes get us only so far. Most of the time, we have a person like Masters—someone who has done something atrocious without anything like a large tumor or hole in the skull to go by. A better approach for revealing the neural origins of crime is to compare the brains of many individuals.
Existing incarceration data has given us a clue about where to focus our attention. Our prisons, for example, contain a disproportionate number of people with significant mental illness, including psychopathy and antisocial personality disorder (a related but broader condition listed in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders). Psychopaths have just the traits you’d expect to find in people behind bars: selfishness, superficial charm, impulsivity, dishonesty, irresponsibility, and lack of empathy or concern for others. And though they make up only 1 to 2 percent of the general population, they represent a whopping 15 to 25 percent of those incarcerated. The evidence related to traumatic brain injuries is similarly stark: while less than 9 percent of those outside of prison have experienced such trauma, roughly 60 percent of those in prison have had at least one such injury.
Although the basic approach of criminal neuroscience shares a lot with early physiognomy, our tools have come a long way from Frigerio’s otometer. Computed tomography (CT) and magnetic resonance imaging (MRI) scans capture the structure of the brain at a moment in time. You can think about the images they produce as a snapshot of the contents of our skulls: an interior brain Polaroid. Their primary value comes in revealing trauma, disease, or abnormality: they can show whether a person has an egg-sized tumor or an abnormally small amount of tissue in a particular area of the brain. A functional magnetic resonance imaging (fMRI) scan, by contrast, reveals which areas of the brain are recruiting more oxygenated blood over time—that is, it gives us a sense of where neural activity is concentrated when a person is being asked a question or looking at a series of images (such as sexually explicit pictures of adults and children). This neuroimaging technology has allowed us to identify correlations between brain structures, on the one hand, and activities and behaviors, on the other.
Take the prefrontal cortex. Pathological liars, highly aggressive people, and those with antisocial personality disorder tend to have less gray matter in this area. There are also links between violent behavior and injuries to the prefrontal cortex, and between having a criminal record and reduced blood flow in this part of the brain. This aligns with other research showing that the prefrontal cortex plays a crucial role in impulse control, including a person’s ability to make prudent long-term decisions, delay gratification, and adhere to rules.
One of the strangest aspects of prefrontal cortex dysfunction is that someone with damage in this region of the brain may understand the difference between right and wrong but nonetheless be unable to act in a moral fashion. Mr. Oft’s case would seem a prime example: he was aware that his actions were reprehensible even as he reported being powerless to control them.
Given the complexities of antisocial behavior, it is not terribly surprising that other parts of the brain also influence criminality. The amygdala, for instance, is thought to play an important role in regulating aggression. Neuroscientists have identified this area as critical for understanding the beliefs, intents, desires, and emotions of others. When it is not functioning properly, a person may be at an increased risk of committing violence, because it is the ability to appreciate the shock, fear, and distress of others that helps prevent us from harming people. We have known for a long time that psychopaths have significant empathy deficits—and sure enough, their amygdalae
are less active than those of people in the general population.
Although we’ve been considering them in isolation, the parts of the brain are interconnected, and deficits in multiple areas may contribute to a particular criminal behavior. Pedophilia, for example, seems to involve an array of deficits at the neural level, including problems with the amygdala and frontal cortex that interfere with how a person processes emotional cues and sexual stimuli.
But the location of the abnormality or dysfunction may affect the nature of the crime that a person is disposed to commit. Those who have deficiencies in their prefrontal cortex appear more likely to commit crimes that demonstrate impulsivity and emotional arousal (smashing someone in the head with a bottle after being ridiculed, for example). By contrast, those with demonstrated abnormal activity in their amygdala—but fairly unexceptional activity in their prefrontal cortexes—appear more likely to engage in calculated, directed, and emotionless aggression (gathering tools and stalking someone for weeks before brutally murdering her to steal her jewelry). Both dysfunctions might lead to murder, but they involve different neural structures and processes.
Some researchers have argued that this may explain the contrasting behaviors associated with “acquired psychopathy,” which tends to involve reactive aggression brought on by immediate dangers or frustrations, and “developmental psychopathy,” which tends to involve instrumental aggression directed at accomplishing selfish ends. Those with acquired psychopathy have suffered an injury to their prefrontal cortex that makes it hard for them to regulate their emotional responses, while those with developmental psychopathy have dysfunctional amygdalae that prevent them from properly processing signals of distress.
Television shows and movies lead us to regard psychopaths either as pure evil (think Michael Myers in the Halloween slasher films) or as hyper-rational actors who simply choose to do horrible things (think Hannibal Lecter), but the science offers a very different explanation for their behavior: they have abnormal brains that leave them without critical tools that the rest of us take for granted. As we’ll explore later, we are reluctant to embrace this biological account because it makes it harder for us to justify our harsh treatment of criminals. But it’s what the best evidence suggests. And the case against our simplistic “mug shot” view of defendants is made even stronger when we consider what causes brain dysfunction in the first place: genetic and developmental factors that are mostly beyond the control of the person they affect.
Some scientists have claimed that roughly half of the variability in antisocial traits across the population comes down to the genes that people are born with. All things being equal, if you have a Y chromosome, you are several times more likely to engage in violent criminal behavior. And psychopaths and pedophiles are both disproportionately men. But it can be hard to separate out the impact of genes from social factors: after all, men and women are subjected to very different arrays of experiences and expectations.
A good example of the interplay between genes and environment is the enzyme monoamine oxidase A (MAO-A), which breaks down certain neurotransmitters and is encoded on a single gene. Scientists have suggested that if you happen to have a version of this gene that produces less of the enzyme, your likelihood of committing a violent crime by age twenty-five is increased several hundred times, but only if you’ve also experienced early childhood abuse.
On a more general level, the environment can play a powerful role in how our brains develop, particularly during the prenatal, infant, and early childhood periods, with a resulting impact on future criminality. There are head injuries, yes, but also experiences that shape us and may increase our likelihood of eventually breaking the law.
Some of those experiences have to do with missing out on key things that our bodies need to build a healthy brain. A wealth of evidence, for example, shows that nutritional deficiencies in the womb and during childhood can lead to cognitive dysfunction. Even micronutrients appear to matter: several studies link low levels of trace elements like zinc and iron with increased aggression.
Exposure to certain toxic substances can also play a role. If your mother smokes during pregnancy, you are approximately three times more likely to commit a crime in adulthood. And similar patterns emerge with respect to alcohol abuse. Particularly disturbing are the elements outside a mother’s control: if you’re born in a certain neighborhood in a certain country at a certain time, you may be exposed to heavy metals linked to violent behavior every time you drink a glass of water or breathe.
There is growing evidence, for instance, that lead poisoning from gasoline may have been a major contributor to the sharp rise in violent crime between the 1960s and 1990s. The theory is that kids were exposed to airborne lead dust from car emissions in the 1940s and 1950s, which led to reduced brain volumes and dysfunction, particularly in the frontal cortex (again, the part of the brain that frequently shows abnormality in violent populations). As a result, two decades later, those with high exposure had a reduced ability to regulate their emotions and impulses, with criminal consequences.
Other critical experiences come from interpersonal interactions. It matters what your parents, siblings, friends, and neighbors are like. Having a mother and father who are abusive or neglectful, being an outcast at school, and falling in with delinquent friends all seem to increase one’s likelihood of committing a crime.
And many of these risk factors appear to have a multiplicative effect: a hyperactive ten-year-old with a low IQ living in poverty with an antisocial single mother who engages in harsh discipline and frequent abuse—all known predictors of delinquency—is several times more likely to commit a violent crime by age eighteen than a ten-year-old who simply has a low IQ.
Even when genes and environment leave a person at a low risk of criminality, being in a certain age group may bump it up. We know that people in their late teens and early twenties are disproportionately represented in the rolls of criminal offenders. A recent survey from Great Britain found that people between sixteen and twenty-four were behind more violent crimes than all other age groups taken together.
Part of the explanation is that our brains develop, just like the rest of our bodies—but in fact more slowly than the rest of our bodies. The frontal lobes, particularly the areas that regulate judgment, decision-making, and self-control, may not completely mature until people are well into their twenties. As you’d expect from looking at their brains, adolescents tend to be less adept at considering the consequences of their actions. Lacking the fully formed quick-decision-making structures that steer adults away from potentially dangerous criminal activities without needing to deliberate, adolescents sometimes get lost trying to figure out how risky something is: Should I pull the gun out of my pocket? Should I throw this bottle at that car? Should I inhale this drug? According to one theory, part of the problem may be that while the prefrontal cortex is a late bloomer, the amygdala—which deals with emotional reactions and reward processing—is a precocious debutante, leaving those in their late teens very susceptible to the allure of criminal actions and the sway of their emotions.
From an evolutionary perspective, the adolescent brain’s characteristics and its lengthy development seem baffling, but some scientists believe that the distinctive features of the adolescent brain that spawn risk-taking and novelty-seeking may actually have been adaptive in our ancestral past, encouraging adolescents to move out into the world, develop new social connections, gain valuable new experience, and take the chances necessary for success in a competitive environment. We may get caught up considering the current costs of a youthful mind—measured in alcohol and drug overdoses, car accidents, fights, and arrests—and miss the benefits of an adolescent brain: the willingness to experiment, to meet new people, the endless desire for learning, feeling, and knowing what the world has to offer.
One bright sign is that in recent cases a majority of Supreme Court justices have seemed to accept the scientific evidence that there is a fundamental diff
erence between juvenile minds and adult ones. In both Graham v. Florida, which eliminated sentences of life without parole for juvenile offenders who did not commit homicide, and Roper v. Simmons, which abolished the death penalty for those under eighteen, the Court noted that young people are not only more vulnerable to peer and other outside pressures but may also lack the psychological development to act responsibly. We need to extend this new understanding to all people, young and old, whose brain function leaves them at special risk.
Yet convincing the Supreme Court and the broader public that crimes often reflect neural deficits is just half the battle against the “mug shot” view of criminality. To eliminate the myth that poor character or an evil soul is behind criminal behavior, we also need to establish that even those without brain abnormalities are subject to powerful situational influences that shape the decision to break the law. Genetic, biological, and experiential factors leave some individuals at a vastly higher risk of committing a crime, but most people’s moral identities are never set in stone. The particular circumstances in which we find ourselves can make all the difference.
—
Two seeds from the same pod can grow into very different trees. Just look at the Bulger boys: James (nicknamed Whitey) and William (called Bill).
They were raised in South Boston, two of the six children of James and Jean Bulger. The elder James had lost part of his arm after an accident and struggled to find steady work, so the family lived in Old Harbor, the first public housing project built in New England. Whitey and Bill shared a room with their younger brother, Jackie, until Bill was a sophomore in high school, while the girls were together in a room down the hall. Though the project has since been taken over by drugs and despair, back then Old Harbor was a community of two-parent households, poor but striving. The Bulgers did not have much, but they had their family and they had their dignity.
Unfair Page 7