The Anatomy of Violence (14 page)

So there we have them.
Bustamante, Kraft, and Raine. Three different individuals with different yet somewhat similar backgrounds and brains. We’ve seen that the prefrontal cortex is a key brain area that is dysfunctional in murderers. And while I’d like to emphasize that fact, the exception presented by Randy Kraft gives us pause. While we cannot read too much into one case study, such fascinating individuals do, as we’re about to see, generate interesting hypotheses for further testing.

Analyzing Randy’s brain made us reflect upon an important distinction in violence research—between “proactive” and “reactive” aggression. This distinction has been around for a long time in the work of
Ken Dodge, at Duke, and
Reid Meloy, in San Diego. The basic idea is that some predatory people—the proactives—use violence to get what they want in life.

Randy was proactively aggressive. He carefully planned his actions, drugging his victims, having sex with them, and then impassionately dispatching them. Like a good computer specialist, he was methodical, logical, calculating, and an able trouble-shooter of problems. Proactively aggressive kids will
bully others to get their money, games, and candy. There’s a means to an end. Proactives plan ahead. They are regulated, controlled, and driven by
rewards that are either external and material or internal and psychological. They are also cold-blooded and dispassionate. They’ll carefully plan the heist they have been thinking through, and they’ll not think twice about killing if need
be. Quite a lot of serial killers fit this bill—like
Harold Shipman, in England, who killed an estimated 284, most of them elderly women; Ted
Kaczynski, the Unabomber, whose
terror campaign was conducted with mail bombs;
Peter Sutcliffe, who bumped off thirteen women in the north of England; and
Ted Bundy, who carefully killed about thirty-five young women, many of them college students.

Flip the aggression coin and the other side to the Randy
Krafts of the world are “reactive” aggressives. These more hot-blooded individuals lash out emotionally in the face of a provocative stimulus. Someone has insulted them and called them names. They’ve lent money and it has not been returned. They’ve been verbally threatened. So they hit back in
anger.

Take Ron and
Reggie Kray, two
identical twins who grew up in east London and operated in the swinging ’60s, the same time that Randy Kraft was operating in Southern California. Reggie Kray’s killing of
Jack “the Hat” McVitie was an example of reactive aggression. It went like this.

McVitie had said mean things about Reggie’s schizophrenic twin brother, Ron. True,
Ron Kray was fond of his food, and yes, he enjoyed exploring the boundaries of his sexuality. But there are more subtle ways of expressing these facts than to call him “a fat poof,” as Jack “the Hat” did. Jack also owed the Kray twins a hundred pounds, which did not help things. Adding injury to insult, one night walking out of a Chinese restaurant, Reggie bumped into McVitie, who said, “I’ll kill you, Kray, if it’s the last fucking thing I do.”
¹⁷
Now, that’s not nice.

Reggie decided that that was going to be Jack McVitie’s last supper. Later that night Reggie pushed a knife into McVitie’s face and stabbed him to death in an explosive fit of pent-up anger. Reggie would have blown Jack’s head off, but his .32 automatic jammed twice, so he had to use a knife instead. Reactive aggression is much more emotional and unregulated. So in this context, although they were both murderers, Kraft and Kray were more like apples and oranges.

Given this proactive-reactive subdivision, I decided to categorize our forty-one murderers into proactive, predatory killers and reactive, emotional killers. We scanned all sources for all the information that we could dredge up on our subjects—attorney records, preliminary-hearing transcripts, court transcripts, national and local newspaper stories, reports and interviews from psychologists, psychiatrists, and social workers, and of course rap sheets. We even interviewed some of the
previous prosecution and defense attorneys for more information on the killings. In the end, we classified twenty-four murderers as “reactive” killers and fifteen as “proactive” killers.
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In a number of the homicides there were elements of both proactive and reactive aggression, so they were left unclassified.
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Think of a
revenge killing, for example. Someone gets really upset by an insult, and in response they set about carefully getting their own back. They are indeed reacting to a slight, but they plan their sweet revenge carefully and thoughtfully, and obtain satisfaction in doing so—a psychological gain. They are not unlike
terrorists who react to a sociopolitical, ideological insult by carefully planning a counterattack.

The results of our reactive-proactive comparisons are illustrated in
Figure 3.4
, in the color-plate section. Here you’re looking down on the
brain and the
prefrontal cortex is again at the top. This time the subregion you see is called the
ventral—or underneath—prefrontal cortex. The reactive, hot-blooded murderer has low prefrontal
functioning in the ventral subregion. In contrast, the predatory, cold-blooded killer has just as much prefrontal activation as the normal controls. Like Randy
Kraft, they’ve got the goods to make a cold, calculated kill. In contrast, the hot-blooded killers are not so hot when it comes to prefrontal regulatory activation.

We see here—even at a visual level—that homicide is nuanced. Yes, there is a cerebral basis to violence. And yes, the prefrontal cortex is one of the culprits. But even among the tiny proportion of us who kill there are differences. Our group of predatory, proactive killers features the same regulatory brain control as Randy. The brain anatomy of murder is color-coded on a reactive-proactive aggression spectrum.

Wait a bit. If these predatory killers have relatively normal prefrontal functioning, what made them killers in the first place?

Let’s plumb the depths of the murderous mind. Deeper down in the brain, well below the civilized upper crust of the prefrontal cortex, we arrive at the limbic system, site of the emotions, and the more primitive parts of our neural makeup. Here the
amygdala fires up our emotions and stimulates both predatory and
affective attack.
^20
,
21
The
hippocampus modulates and regulates aggression and when stimulated sets in motion predatory attack.
^22
,
23
The
thalamus is a relay station
between the emotional limbic areas and the regulatory cortical areas. The
midbrain when stoked up gives expression to full-blooded affective emotional aggression.
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We combined these regions to get an overall measure of subcortical activation in the
reactive
murderers, the proactive murderers, and the normal controls. We found that
both
murderer groups showed
higher
activation of these subcortical limbic regions than the controls, especially in the more “emotional” right hemisphere of the brain. Below the façade of the boy-next-door that many cold-blooded killers are able to portray, there’s a lot bubbling under in that deeper subcortical cauldron of brain functioning.

What exactly is going on here? We can think of these deeper limbic emotion-related brain regions as partly being responsible for deep-seated aggression and rage, which both groups of killers have in common. The difference, however, is that the cold-blooded killers have sufficient
prefrontal regulatory resources to act out their aggression in a relatively careful and premeditated fashion. They feel as angry as anyone, but instead of getting mad, they get even. In contrast, while the hot-blooded killers also have a mass of angry feelings simmering away, they don’t have sufficient prefrontal resources to express their anger in a controlled and regulated fashion. Someone gets their goat, they see red, and they blow their lid. Before you know it, blood flows.

This seeming paradox of good frontal regulatory control and increased limbic activation in predatory, proactive killers can be exemplified by a number of serial killers. Take
Ted Bundy, who may have killed as many as a hundred women and girls, mostly college students. His homicides were the epitome of planning. With his arm in a sling to make him look vulnerable, Bundy would politely ask a young woman to help him carry something to his car. Using his beguiling charm, good looks, and debonair manners, he would lure her to a safe place where with demonic fury he would tear into her—biting her buttocks, gnawing her nipples, and bashing her head in a
sexual orgy that ended in a brutal beating and killing. Despite all the planning and forethought that carefully preceded his attacks, once that stealthy lion had stalked his prey, he unleashed with ferocious fury the ultimate attack. The emotional limbic cauldron was overflowing into an unbridled, unregulated killing.

The study I did with
Monte, like all initial findings, requires replication and extension. Another study of eleven impulsive murderers
also using the
continuous-performance task replicated our findings of reduced prefrontal activation.
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Yet because these studies are so hard to conduct, the reality is that virtually no other research group has been able to build upon and extend our initial findings on
murderers.
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For many researchers, linking the
brain to homicide is a bridge too far. Nobody can cross it.

I take our instrumental proactive murderers as a model for serial killers, on whom we know very little scientifically. If I could perform brain scans on a significant group of serial killers, I might expect a brain profile similar to our proactively aggressive killers—a hotbed of seething limbic activation bubbling under the good prefrontal
functioning that allows them to carefully plan their actions. Yet even within this pack of serial killers, make no mistake—there will inevitably be several shades of gray lurking in the etiological shadows.

We’ve seen that the prefrontal cortex is critical in regulating and controlling both behavior and emotion. We’ve also seen that excessive subcortical activity may fuel the heightened emotion that we see in our violent offenders. We could stop there in our mapping of the mind of the murderer. We have the essence here in a nutshell. Yet as I readily acknowledged above, the scientific reality would be that we are being overly simplistic. We get back to the complexity of homicide, psychopathy, and criminal offending, and the inevitability that any attempt to explain and understand such behavior through functional neuroanatomy—the workings of the brain—is going to be enormously complex. Here I’ll give you just a piece of the exciting neuroanatomical action that is taking place today in our probing of the murderous mind.

Moving from the front of the brain, where we have been focusing, to the relatively less explored posterior part, we’ll start with the
angular gyrus—area 39 in the map created by the German anatomist
Korbinian Brodmann in 1909. The angular gyrus lies in the inferior, or lower, half of the
parietal lobe, above the superior
temporal cortex, and in front of the
visual cortex. It is consequently in a prime position in the brain, lying at the junction of three of the four major lobes—the parietal, the temporal, and the
occipital cortices. It connects and integrates information from many modalities—visual, auditory, somatosensory, vestibular—in order to perform complex functions. It lies on the surface
of the
brain. Find the top of your ear with your fingers and move them up a couple of inches—1.5 inches behind that spot is about where the angular gyrus lies.

We imaged the angular gyrus in our murderers and found significantly lower
glucose metabolism in this structure than in those of the controls. In Sweden, researchers also found reduced cerebral blood flow in this area of the brain in
impulsive, violent criminals.
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Other researchers have argued for angular gyral dysfunction in violent offenders as well.
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How might dysfunction of the angular gyrus translate to violence and offending? The angular gyrus is one of the latest areas of the brain to develop, and so, not surprisingly, the abilities it governs are complex and sophisticated. Unlike the
visual cortex, which comes online immediately for the newborn infant, the angular gyrus subserves functions that include reading and arithmetic, abilities that as we know do not start early in life, but develop much later in childhood. So, for example, reductions in glucose metabolism in the left angular gyrus have been associated with reduced
verbal ability,
²⁹
while damage to this region in neurological patients results in problems with reading and arithmetic
³⁰
—complex functions that involve integration of information across multiple domains. Writing ability is also affected in a subtle way. For example, letters may be missing or duplicated, or be widely spaced. Punctuation is off, and capital letters may be disregarded.

So if the angular gyrus is not functioning well, then a child’s reading, writing, and arithmetic are going to suffer—the three R’s that are the foundations of scholastic performance. What do we know about violent offenders? They do poorly at school. If you do poorly at school, you’ll have a problem getting a job. You won’t get as much money as you’d like. You’ll then be more likely to use violence to get what you want in life—things you cannot get because of your educational
failure. The root cause may be brain-based, but the path to violence may well lie along school and occupational failure—a social/educational process.

The
hippocampus and its surrounding area, the
parahippocampal gyrus, is another brain region that is disturbed in offenders. The hippocampus lies just behind the
amygdala and its Latin name means sea horse. We’ve touched on this area above in connection with our sample of murderers, and other researchers are also finding that offenders have functional disturbances in this brain region. One study on antisocial, conduct-disordered boys from London showed reduced function of the
hippocampus during an attention task.
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In Sweden, the neuroscientist
Henrik Soderstrom found reduced hippocampal functioning to be associated with higher psychopathy scores in violent offenders.
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In the United States,
Kent Kiehl has argued that the parahippocampal gyrus contributes to symptoms of psychopathy.
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Researchers in Germany led by
Jürgen Müller also found reduced parahippocampal functioning in adult psychopaths,
³⁴
while
Daniel Amen in California found the same finding in impulsive murderers.
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