Torturing, aggressively attacking and sexually
assaulting victims are the most common behaviour portrayed by serial killers
(Warren et.al 1996, pp. 5). Keeney & Heide (1995, pp. 3) stated that
according to Cormier et. al. (1992), serial killing consists of numerous
victims murdered in distinct locations within a significant break of time. The
most common question raised upon serial killing issues is how serial killers
develop their vicious behaviours. Focuses are pointed towards whether the
behaviours are possessed naturally or triggered by environments and upbringings.
Although Ioana (2013, pp. 324) claims that surrounding and family upbringings
play a role in developing serial killers behaviour, The Minnesota Twin Study
has claimed that 60 percent of what shapes a serial killer is biological,
rather than upbringing issues (Brogaard 2012). This essay argues that
biological traits contribute the most substantial roles in the moulding of
serial killers behaviour, based on the findings on brain defect activities and malformed
Sentence: It can be argued
that there are many sociological and environmental factors that promote the
sadistic behaviour of serial killers.
90 percent of serial killers come from problematic or dysfunctional families
Hicky, a criminologist, found that 48 percent of 62 male serial killers had
been rejected as children by a parent or other important people in their lives
(American Academy of Experts in Traumatic Stress, n.d.).
killers share the same childhood experiences: either psychologically,
physically or sexually abused (Raven 2009).
experiences and repeated psychological trauma cause a child to seek relief
through activities involving violence (American Academy of Experts in Traumatic
Jeffrey Dahmer once was described by his father as a cheerful and enthusiastic
Despite the contribution of
sociological and environmental factors to the development of serial killers
behaviour, a research conducted by Dr. Richard Davidson in 2000 shows
distinctive results; that genetics play a major role in the behavioural
formation of individuals. The research comprises 500 brain scans of people who
are considered vulnerable to criminal behaviour and people who are normal, of
which the result demonstrates different brain activities on these people’s
brains (American Academy of Experts in Traumatic Stress, n.d.). According to
American Academy of Experts in Traumatic Stress (n.d.), there are three parts
of brain which relate to each other and have important roles in controlling
positive and negative emotions, such as the orbital frontal cortex which is
responsible to control and restrain emotional outbursts, the anterior
cingulated cortex which deals with responses to conflicts, and the amygdale
which controls responses to fear (American Academy of Experts in Traumatic
Stress, n.d.). Result of the research indicates that the activity in the
orbital frontal cortex and the anterior cingulated cortex has reduced or was
even non-existent, contrasted with the activity in the amygdala which stayed on
the same level and elevated (American Academy of Experts in Traumatic Stress,
n.d.). Correspondingly, this data supports the fact that many people who have
experienced traumatic childhood do not end up being serial killers (American
Academy of Experts in Traumatic Stress, n.d.).
Sentence: It is claimed
that men who suffer from Klinefelter’s Syndrome are more likely to commit
criminal behaviour (Kirstine et.al 2018, pp. 1).
genetic formula = 46XX, male genetic formula = 46XY (Ioana 2013, pp.325).
Syndrome is the chromosome abnormalities in which an additional X chromosome
exists in a person’s system (Ioana 2013, pp.325).
diagnosed with Klinefelter’s Syndrome is prone to criminal behaviour, including
sexual abuse, arson and serial murder (Kirstine et.al 2018, pp. 1).
In order to understand the development of serial
killers behaviour, the aspects of nature and nurture must be considered.
Although environment and upbringing factors are likely to trigger the sadistic
behaviour of serial killers, biological traits contribute as the main role in the
formation of this behaviour. Brain defect activities and the malformed
chromosome named Klinefelter’s Syndrome suggest that nature stimulates
individuals with these abnormalities to cross the boundary to from leading a
normal life to committing serial murders.