Blog Post #3: How a Person Could Become a Serial Killer

Are Serial Killers Born Bad or Man-Made Monsters? ‹ CrimeReads

How Does a Person Become a Serial Killer:

As a quick reminder my inquiry question is “What is Happening Inside the Mind of a Serial Killer”. In my last blog post about my Project Plan my first step to figuring out my answer to this inquiry question is How does a person become a serial killer. Could it be due to their living environment, genetics, etc. If you would like to know about this please do keep on reading as it may interest you.

Definition of a serial killer is someone who murdered at least three people and seeks for psychological gratification. (4)

A question that I want to ask you before you keep on reading is do you think a serial killer can either be born or made? If you do have an answer to this please do share it in the comments as I want to see what else people think. 

An American psychiatrist Dr. Dorothy Lewis has researched ways how a person can become a serial killer. She found that serial killers can never be born and that they were to become one due to their living environment that could activate the evilness in people. (2) An American neuroscientist and professor at UC Irvine School of Medicine Jim Fallon thought of the same idea but from a  different experiment. Dr. Fallon did a blind trial where his colleagues sent him 70 brain scans that consist of people with diagnoses, no diagnoses like depression, and brains of killers. Dr. Fallon noticed something with every killer’s brain. He had found a pattern that every killer has lost function in their orbital cortex which is above your eyes. While the orbital cortex would give you a sense of morality, conscience, and ethics if it is gone or isn’t developed the person would have no sense of morality and have little control of their actions. Dr. Fallon had thought of an idea to look at an MRI of his brain. As he looked at his scan he found that he had the same brain as a killer but the question is why isn’t he a killer. He found that genetics could be the cause. (3) There is a gene that produces an enzyme called MAOA that would regulate your level of neurotransmitters that are involved in impulse control. It was found that if you have a lack of MAOA gene or have a little activity variant you would be predisposed to violence. The variant is called the warrior gene. About 30% of men have the warrior gene but the gene would only be triggered depending on what happens to you in your childhood. Dr.Fallon discovered that his family tree had a large number of murderers so he took a genetic test to see if he had the genes. (1) Dr. Fallon then  found that he had a large amount of this enzyme MAOA and was able to not become a serial killer due to being loved and cared for during his childhood. (3) Which being said that the killer combination is the genetic MAOA aka warrior genes mixed together with an abusive childhood would cause a killer to break out. There were researchers that have explored that different kids have different ways of approaching a situation and how they would adapt to it. There were differences that could be noticed to the different childhood experiences. Neurological, biological, mental, emotional play an important role to the development of an individual and changing them by influencing them in a negative way could cause the criminal behaviour. To serial killers nature and nurture are very important to them. The nurture factors would depend on the parental behaviour and ability of their kids as nature could affect others from violence and crime.(5)

There are a lot more studies of how a person can become a serial killer but I thought that this one was the most interesting since I watched a small clip about Dr. Jim Fallon on “The Doctors” where they talked about his experiment looking at the brain scans and what he had found. I hope you found this blog post very interesting as I did while writing it  and I hope you read my next blog post which is how they think and feel about killing someone.

  1. BBC News, B. B. C. N. (2015, March 9). Are murderers born or made? BBC News. Retrieved November 14, 2021, from
  2. Narula, K. (2020, November 24). Are serial killers born or made? the doc about genetics vs. nature. Film Daily. Retrieved November 15, 2021, from     
  3. Taylor, S. (2020, November 30). Are serial killers born or made? | psychology Today Canada. Psychology Today. Retrieved November 13, 2021, from
  4. Unal, B. (2021, June 11). Are serial killers born or made? – IACS: Institute for Asian Crime and Security. IACS. Retrieved November 15, 2021, from
  5.  Vaibhavi, V. (2020, May 4). What provokes a person to become a serial killer? are these factors inborn or are included in their course of life. Legal Desire. Retrieved November 15, 2021, from

4 Replies to “Blog Post #3: How a Person Could Become a Serial Killer”

  1. Hi Estella,
    This looks like an amazing project! It looks really intriguing so far, and I am really excited to see your results. I will make sure to check out your last posts!
    Great Work,
    Alexia N.

  2. Hi Estella,
    this topic is so interesting to me and I had never really thought about this before. To respond to your question, I believe serial killers are made not born. There’s no way someone can be born evil enough to kill someone, not just someone many people. In my opinion, it would be a series of situations or trauma that hurt that person so much, they resulted in hurting others.

    A suggestion I have for you is to split up your big paragraphs as it is easier for others as well as yourself to read and follow allow with. Other than that, your blog post is very well researched and was so fascinating to read!

    I’m excited to see more from you and good luck!

  3. Hi Estella,
    I had never thought of this before, and it is such an interesting topic. Some people can benefit from this, too, such as police or those who can prevent situations in which you could face a mischievous and dangerous killer.
    It is usually the hatred and resentment against life that drives serial killers to take lives. In addition, serial killers have been the subject of several books that examine their history and psychopathology.
    Wishing you the best of luck with your research 🙂
    Daniela Z.

  4. Hi Estella,
    This is a fascinating subject. You are right this article is very intriguing and I am glad I got to read about it. In my opinion, I believe it is nurture over nature that creates a serial killer, but I never knew that there was a nature aspect as well that likens ones chance of becoming a killer. It must be strange as a doctor to find out that you could have been a serial killer if even one thing went differently in your childhood. Instead of being saving people you would be killing people, that must be a truly frightening realization.
    I can tell you did a lot of research and are very interested in this topic. I am looking forward to read more of your future posts to learn about other experiments and discoveries made, and the answer to different questions. Have a look at these links, they are quite interesting.

    Chantal M.

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