Abnormalities of the Criminal Mind

Abnormalities of the criminal mind

The relationship between the operation of the human mind and activities that are criminal in nature has always been a long drawn out subject for debate. The discussion always centers on the dispute whether the minds of criminal persons are substantially different from the minds of other human beings. In order to understand the nature of the criminal mind, their differences to other human minds and their petulance for committing crime, it is important to understand who criminals, why they do whatever they do and how their minds function.

Criminal behavior has been defined to include four different types of acts.[1] They include the following:

  1. Acts that are prohibited by both national and international laws.
  2. Acts considered to be immoral from a religious perspective; and which, by religion, is deemed to be punishable by God.
  3. An act that amounts to the violation of community ethics and societal norms and can be punished by the community.
  4. Acts that amount to psychological criminal behavior which are essentially actions that cause serious emotional and mental harm for the victim.

Theories That Explain the Criminal Mind

There are several theories as to the causes of criminal behavior. However, it has been virtually agreed upon that this can be narrowed down to two main causes; genetics and the environment. Past scientific research during the 19th century and 20th century almost always concluded that criminal behavior is dictated by genetics. However, research in the recent past has shown that environment too has a bearing on criminal behavior.

In as much as genetics is considered to play a big role in criminal behavior, the environment on is brought up in also goes some way to determine the nature of a person and their criminal tendencies. Some of the factors that may influence criminality include financial status, social status and the state of the neighborhood one is brought up in.

There are various theories that explain criminal behavior. There are three broad theories that are commonly used to explain such behavior. The first is the psychological approach.

The theory contends that criminal behavior comes about as a result of mental disfunctionality and disturbance or abnormality in the brain of the person committing the crime. Normality has been referred to as that which is considered acceptable by the rest of society. The lack of normality or the absence of it is caused by various factors which may include disease and lack of enough education.

The sociological approach tends to look into criminal behavior from a social angle. The theory postulates that criminal behavior is caused by a combination of factors which may include political, social and economic factors. Proponents of the theory contend that people who engage in criminal behavior learn the same from other people.

The biological approach, as the name suggests, purports that criminal behavior is caused by biology and some flaw occasioned in one’s biological make up. Some of the researchers contend that the criminal mind has suffered various kinds of abnormalities that may be caused by among others; heredity, neurotransmitter dysfunctionality and other types of brain abnormalities that may be caused by factors such as trauma and brain stimulation.

The Abnormalities of the criminal mind; Crime and the Amygdala

With the raging debate as to whether the minds of criminals are different from that of non-criminals, scientists have resorted to the use of positron emission tomography and functional magnetic resource imaging (MRI) in a bid to establish the answers. The two tools are used to examine the functional and anatomical differences of the brains of criminals from other normal human beings.

The most common syndrome found amongst criminals is the antisocial personality disorder, a disorder that is closely related to psychopathy and sociopathy. Scientists have previously been unable to explain why some people tend to behave in an antisocial manner but recent tests and studies have shed some light. These were studies on the part of the brain that controls aggression and sel-control, the amygdala. The amygdala is a part of the limbic system of the brain that controls various emotions in human beings which include response to fear and emotional learning. Scientists argue that the amygdala contributes to certain behaviours that are associated to criminals such as anti-social behavior.[2]

Scientists have observed that in the brains of criminal persons a tract of white matter in the region that connects the amygdala, which directs our emotional responses, with the orbitofrontal cortex, which governs our decision-making capacity, was functioning improperly. The research also shows that the abnormality increases in persons who show a higher level of psychopathy. Further studies show that persons with the antisocial personality disorder have a condition known as atrophy in the regions of the brain called the cortex that controls executive functions in the amygdala. This condition leads to a lack of capacity and this may lead to development of behavior that is lacking in remorse and self control.

Recent MRI scans carried out by scientists have shown that psychopaths tend to show reduced activity in the amygdala region of the brain during aversive conditioning. James Blair developed the Blair Amygdala theory of psychopathy.[3] An excerpt from his article: Fine cuts of empathy and the amygdala: dissociable deficits in psychopathy and autism states as follows:

“The amygdala is thus involved in all the processes that, when impaired, give rise to the functional impairments shown by individuals with psychopathy. It is therefore suggested that amygdala dysfunction is one of the core neural systems implicated in the pathology of psychopathy.”

According to James Blair, people who suffer from dysfunction of the amygdala suffer different kinds of impairment which may include reduced levels of response to threatening stimuli, unlike the normal brain. Amygdala dysfunctioning can also lead to reduced level of emotional response whenever there is an anticipation of punishment and reduced level of response in anticipation of a threat. All these characteristics can be found in criminal persons and as such it can be easily determined that they have amygdala dysfunction.

Furthermore, research has shown that the amygdala is responsible for two other functions in the human brain. It enables aversive emotional response to fear and distress in other people and also helps one to determine that which is right and wrong. Persons with antisocial personality disorder suffer impairment on both of these capacities and therefore they cannot tell the difference between actions that are right and those that are wrong. For the first function, it has been observed that psychopathic persons almost always have reduced response to distress calls by other people. They are unable to process the fear and distress in their victims and are unable to empathize with them because of the impairment of the amygdala which is necessary for the formulation of such stimulus response.

Blair’s theory of impairment of the brain is quite complex and involves other parts of the brain beyond the amygdala such as the ventromedial prefrontal cortex (VMPFC).

Other scientists contend that the ability of the criminal mind to decide whether an action is right or wrong is a purely contextual one and cannot be wholly explained by science. Some studies show that the amygdala is not active in criminals or psychopaths who are thinking about immoral and criminal acts while it is active in people who are non-psychopaths but pondering about the same moral dilemma. In the words of J Edersheim[4],

“Criminals come in all flavors, some are motive driven and know right from wrong, but still they choose to be antisocial. Others are impulsive and aggressive. So, different kinds of people commit different kinds of offenses.”

The Ventromedial Frontal Cortex and its relation to criminal minds

Studies have also shown that injury occasioned to the frontal lobes of the brain may lead to one engaging in activities that are criminal in nature. The Ventromedial frontal cortex is the part of the brain that deals with planning, self control and judgment. This is the part of the brain that is most affected by alcohol and therefore is really a determinant of the behavior of a person.[5]

Tests on this part of the brain have been done on both humans with brain lesions as well as other primates whose brains are similar to that of man. Damage to the frontal cortex leads to disruption of the ability of humans to perform various actions and also leads to impairment n the processing of various kinds of stimuli. The social behavior of humans is widely disrupted by damage to the frontal cortex.

Persons who previously had normal abilities to lead acceptable social lives and to conform to the acceptable social norms lose this ability and are then unable to perform such activities. They are even unable to make decisions on matters relating to their own personal lives. However, what is remarkable about the damage to the frontal cortex is that victims of such damage retain their intellectual abilities. This is seen in their ability to perform well in executive tests while also retaining their ability to learn and good memory.

The flipside is that patients suffering from frontal cortex damage develop abnormality in their processing of emotions and feelings. This is the difference between the criminal mind and the normal human mind. The mind of a person who has suffered from damage of the ventromedial frontal cortex is unable to process stimuli relating to emotions and feelings. As such, they are unable to feel remorse whenever they do criminal acts.

The availability of relevant social knowledge to such persons coupled with their inability to apply reason and logic to such knowledge led to the development of the somatic marker hypothesis.[6]

The somatic marker hypothesis contends that arising of defects in one’s ability to process emotions and feelings influences the making of impaired decisions. Emotional changes in the brain are represented through the state of the body, and such changes are always represented in the mind in the form of somatosensory structures which gives rise to the term ‘somatic state’.

The somatic marker hypothesis is a complex one but goes some way towards explaining the relation between damage of the ventromedial frontal cortex and the criminal mind or psychopathy in humans.

Callous and Unemotional Traits (CU Traits) in criminal minds

It has been scientifically proven that callous and unemotional traits lead to antisocial behavior and criminal tendencies in human beings[7]. CU traits have been found to be contributory to aggressive behavior, aggressiveness and impulsivity.[8]

The studies show that especially among adolescents, CU traits cause temperament that is always characterized by a reduced ability to process stimuli related to emotional arousal of fear and distress in others. Furthermore, CU traits lead to abnormality relating to ones response in anticipation of punishment and danger.[9]

CU traits are known to highly hereditary and therefore the likelihood of being passed on from parent to child is very high. As such it helps develop the theory that criminal behavior in human beings is genetic. CU traits constitute what can be described as fledgling psychopathy as their presence in the brains of kids and adolescents gradually leads to the development of psychopathy and criminal mind.

A research by a group of scientists in 2009 showed that a group of boys with CU traits exhibited different reactions to a set of actions as compared to their colleagues who had healthy amygdala functioning. The research showed that the boys showed neutral faces to exposed to actions considered as normally arising fearful reactions from normal persons.[10]


As seen in the discussion, criminal minds show different types of abnormalities as compared to the normal human brain. The debate as to whether science can actually prove the disparities in the functioning of the human brain seems to have finally been settled. Through science, it is therefore possible to study the human mind and arrive at a way of curing crime in society.

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