What is wrong with the brains of serial killers?

I am not a psychiatrist nor am I a psychologist but I did spend nine months at the Univesity of Toronto studying abnormal psychology as part of a four-year program on criminology. I also spent a year as a group counsellor working with mentally ill prisoners. I have also read a number of books on abnormal psychology in my extensive library in my study in my home. None of this makes me an expert on this subject of serial killers but I am at least knowledgeable to some degree with reference to the minds of serial killers.

It must be obvious to every normal thinking person that there is definitely something very different about serial killers when it comes to the way they think about other human beings. The horror stories we get from victims, police reports and the media will surely convince us that something has to be very different about these people for them to do what they do to other human beings. I should point out however that there is a difference between a mass killer and a serial killer. The prime difference is that the mass killer generally does the killing in one location at one time whereas the serial killer does several or more killings in different places and at different times.

The term, serial killer itself is not a medical diagnosis, but the term serial murder has been defined as far as law enforcement is concerned so it is very useful to them to understand the behavioral traits of these kinds of killers whose behaviors are unique to the these types of person who are likely to offend again if not apprehended. But what psychological diagnoses could account for this kind of behavior? This question is made even more important by the fact that forming opinions consisting solely of serial killer’s minds can be extremely difficult to establish.

Whatever turns a person into a serial killer, it has to be encoded in their brains.  I would like to explain to my readers some of the psychological disorders that could be behind the possibility for a person being a serial killer.  Firstly, I would like to clarify what is meant by the term, ‘encoded in the brain.’ It simply means that at any moments in time, all of our brains have developed in various particular ways that controls the statistical likelihood of certain behaviors occurring under certain circumstances in the way we were developing from the time we were born and onward as we grew older

The most broadly recognized mental disorder associated with serial killing is referred to as Antisocial Personality Disorder (APD) and is intimately related with psychopathy. Psychopathy is not a clinical diagnosis, but it is considered a developmental disorder by neuroscientists. Many individuals with APD are not psychopathic, but a number of them are especially the ones who exhibit traits such as limited empathy and grandiosity, do demonstrate a form of psychopathy. Serial killers possess psychopathic traits such as charm, manipulation, and intimidation that have been recognized by the US Federal Bureau of Investigation (F.B.I) as being thoroughly connected to serial murders although it’s important to realize that not all psychopaths are serial killers.

A point to note about psychopathy is that we know the kinds of behaviors psychopaths reliably exhibit (such as superficial charm and a lack of empathy towards others. We know that they typically have a low resting heart rate and we also know that that these kinds of killers are most likely to have significant differences in their brains, such as reduced prefrontal gray matter (the  area of our brains where our emotions are formed)  abnormalities and asymmetric hippocampi. (numerous studies have reported a smaller hippocampal volume in Alzheimer's disease).  

One can only speculate how these brain differences could be implicated in psychopathic behavior, but it does mean that if the brains of these kinds of killers are scanned and their heart rates are measured, these are the kind of differences we could expect to find in these killers.

Could there be any other mental condition implicated in serial killing, other than psychopathy or APD? We can only speculate, but a good place to look would be at the other personality disorders. Borderline Personality Disorder (BPD) is characterized by emotional instability, anxiety, and psychotic-like symptoms where those afflicted can suddenly become very paranoid or suspicious of others.  BPD has also been included as a disorder that results in zero degrees of empathy, a term used to describe conditions where the serial killer and other psychopaths do not seem to have any empathy for others and is also often coupled with impulsive aggression.

So how could BPD result in the creation of a serial killer? We can only speculate, but suddenly becoming very paranoid or suspicious of others, having no empathy for anyone, and perhaps being subject to impulsive aggression, means that should an individual with BPD display all of these traits at once, there could be an murderous assault that results in the loss of life. If there is a situational or environmental trigger for these outbursts, the killing could become serial.  This would be in contrast to psychopathic serial killers, where the killing is usually pre-meditated.

The brains of those with BPD are less understood. Impulsive aggression is characteristic of disorders these killers suffer from. This seems to be related to low levels of serotonin (serotonin is primarily found in the gastrointestinal tract, blood platelets, and the central nervous system).  This has resulted in attempts to treat BPD with SSRIs. Scientists have found altered levels of metabolism in the anterior cingulate cortex and reduced matter in the prefrontal cortex in those with BPD. 

Millions of Americans and others around the world suffer from depression, anxiety, and other mental health conditions. Selective serotonin reuptake inhibitors (SSRIs) can improve a wide variety of these conditions and, as a result, are commonly prescribed. SSRIs work by blocking a receptor in brain cells that reabsorb the chemical serotonin, thereby giving these unfortunate sufferers more of this chemical available to "amplify" its ability to send messages between nerve cells. 

Let me make it quite clear. Very few of those persons suffering from depression and anxiety ever turn out to be serial killers or even killers of another nature.

There do not seem to be any neurological studies that have found anything special about Narcissistic Personality Disorder (NPD), another mental disorder. But NPD is another disorder where the afflicted have no empathy for others. This automatically suggests prefrontal and limbic abnormalities, perhaps similar to other disorders unlike BPD, those afflicted with NPD do not suffer temporary psychotic-like symptoms. It must also be acknowledged, here, that psychopaths are very narcissistic, (thinking of themselves only) and so deciding on a diagnosis between APD and NPD is a very difficult task.

The last disorder I would like to mention as a candidate is schizophrenia. Schizophrenics, especially when experiencing psychotic symptoms (such as auditory and visual hallucinations), can become violent. Accounts of schizophrenia and serial murder are mixed. Castle & Hensley (2002) claim that there has never been a validated case of a schizophrenic serial killer, but Dr. Ronald Markman who served as a forensic psychiatrist, (works with criminals) and who detailed the life of Richard Chase, who was also known as The Vampire of Sacramento.  Chase was diagnosed numerous times as a paranoid schizophrenic, before he committed a number of serial murders towards the end of the 1980s.

A common characteristic of schizophrenics, however, is to have jumbled and confused thoughts, which when considered in light of cold, calculated, and premeditated murders, it is harder to merit schizophrenia as a driving force behind serial murder. If our serial killer was a schizophrenic, however, we could expect to see enlarged lateral ventricles (brain tissue surrounding the ventricles has diminished), depleted myelin sheaths in the cerebral cortex, and abnormal clusters of neurons.  

There are other implicated disorders in violent behavior and it must be understood that it is not uncommon to have more than one of them. Schizoid and Schizotypy (in psychology, schizotypy is a theory stating that there is a continuum of personality characteristics and experiences ranging from normal dissociative, imaginative states to more extreme states related to psychosis and in particular, schizophrenia). Personality disorders are known to share similarities with schizophrenia, but again, on their own the probability of them being implicated in serial murder is low to nonexistent. 

As you can see from the aforementioned, serial killers, at least for most of them 

if not all of them, have physical abnormalities in their brains that bring out their impulses to kill human beings. But what triggers them to kill human beings?

In my opinion, there are eight categories of serial killers representing their motives which are—(1) sexual, (2) control over victims (3) thrill killing, (4) following commands of voices in their heads, (5) mission oriented which they are trying to get across to the general public, (6) lust,, 7) seeking fame  and the strangest of all, (8) no motive at all.

In Ted Bundy’s interview on the day before his execution in Florida’s electric chair, he said that the burning motivation to kill was motivated by his unquenchable addiction to pornography.  Certainly not everyone who is addicted to reading pornography is also addicted to killing people. He said that viewing pornography started at an early age and it soon reached a point where viewing it was not enough. The thought of now acting out his erotic passions outweighed his sense of morality, logic and reason. His killings were based on sexual desires. Another of his motives was to have control over his victims.

He was executed in January 1989—eight and a half years after I sat on that same electric chair after being invited as a criminologist to tour that particular prison.

Israel Keyes, the disturbed army veteran, who stalked and killed eight people across several states prior to his capture and suicide in Alaska in December 2012, is the most recent example of a thrill serial killer. The victims of a thrill killer are generally strangers, although the killer may stalk them for a period of time before the attack in order to fuel the thrill of the hunt.

There are some of these killers who seek out and murder their victims because the so-called voices in their heads told them to do it. Miguel Rivera was a serial killer who heard voices in his head believing that God had told him that he was to castrate little boys so that they could be turned into little girls. All five of his victims died so that Rivera could meet his goal to fulfil what he believed was God’s command. He was considered unfit for trial and sent back to a mental institution. It is highly unlikely that he will ever be released again.

Theodore "Ted" Kaczynski who was born on May 22, 1942 and is also known as the "Unabomber”. Between 1978 and 1995, Kaczynski engaged in a nationwide bombing campaign against people involved with modern technology by planting or mailing numerous homemade bombs and ultimately killing a total of three people and injuring 23 others.

Kaczynski sent a letter to The New York Times on April 24, 1995 and promised "to desist from terrorism" if the Times or the Washington Post published his manifesto, Industrial Society and Its Future (also called the Unabomber Manifesto, in which he argued that his bombings were extreme but necessary to attract attention to the erosion of human freedom necessitated by modern technologies requiring large-scale organization. His motive for the bombings was mission oriented.

Edmund Kemper killed for lust reasons. Between May 1972 and April 1973, Kemper embarked on a murder spree that started with six female students and ended with the murders of his mother and her best friend. Previously he killed his grandparents as a juvenile and served five years in a juvenile detention centre. As an adult, Kemper would pick up female students who were hitchhiking, take them to isolated areas where he would stab, shoot or smother his victims. He would then take their lifeless bodies back to his apartment where he would rape their severed heads and bodies and then dissect them. It was his lust that drove him to kill.

At his trial, he pleaded "not guilty" by reason of insanity. He was found guilty in November 1973 of eight counts of murder. He asked for the death penalty, but with capital punishment suspended at that time, he instead received a sentence of life imprisonment. To this day he does not wish to be released from prison for fear of him repeating the same crimes.

Dennis Rader (born March 9, 1945) is an American serial killer who murdered ten people in Sedgwick County (in and around Wichita, Kansas), between 1974 and 1991. He is known as the BTK killer (or the BTK strangler). "BTK" stands for "Bind, Torture, Kill", which was his infamous signature.

He mailed letters describing the details of his ten killings to police and local news outlets during the interval in which the murders took place Because Kansas had no death penalty at the time the murders were committed, life imprisonment was the maximum penalty allowed by law.  Rader would be eligible for parole in 2180 after serving 175 years of imprisonment if he could live that long. He killed his victims because it was his weird way of seeking fame.

Donato Bilancia, 49 was a compulsive gambler who hated to be alone. His victims included four prostitutes, a newly-wed couple, two jewellers, two security guards and two women attacked in the toilets of moving trains. Bilancia strangled or shot them in a rage after he felt "swept by a fire" and a "bite in the head".

 He was given 13 life sentences for murdering 17 people in a six-month rampage that terrorised the Italian Riviera.  The worst serial killer in Italian history asked if doctors could explain to him why he did it. He apparently had  no motive to murder his victims.

Other motivations involved in serial killings are fears of rejection and seeking perfection in others they are attached too. Serial killers tend to be insecure, and irrationally scared of rejection. Such killers will try to avoid developing a painful relationship with their objects of desire and are terrified of being abandoned, humiliated, or exposed. They seek this form of intimacy elsewhere and when they fail to achieve that goal, many serial killers often have the ultimate form of intimacy (sex) with their victims, and often with their corpses. The only other ultimate form of intimacy these weirdos do with their victims is to eat their bodies.

Recent academic estimates of the average number of serial killer victims in the United States alone each year range from 67 to 180 and based on conservative extrapolations from existing data, it could add at least 182 and possibly as many 1,832 victims to the list. These figures may be misleading since often there are the bodies of murder victims that are never found or alternatively never identified as victims. Perhaps the biggest potential pool of overlooked victims is the "misidentified dead," including hospital patients and nursing home residents who are thought to have died from natural causes. In their book The Will to Kill: Making Sense of Senseless Murder, Kenna Quinet and co-authors James Alan Fox and Jack Levin point out that "medical murderers" have, in a few individual cases, killed dozens of people and the authors estimate that their victims can possibly total between  500 to 4,000 a year in the United States.

Later in my blog, I will give you extensive details about various serial killers.