“Are addicts criminals who deserve to be punished?”

“Are addicts criminals who deserve to be punished?” 

Samuel Vorster


During this paper, in response to the statement made at the local forum, known etiological models of addiction would be described. These are, not limited to, the biological, neurobiological, genetic and socio-cultural environmental models, which includes social learning theories. This evidence would depict that addicted individuals should not be treated only as criminals but as patients1.

During the course of addiction, during the stage of initiation, a choice is made by the individual to use substances2. Epigenetic research has shown that through a combination of dormant genes, inherited from the individual’s biological parents, with the initiation of said use, starts the development of a substance use disorder. The severity of the presentation and duration of the substance use disorder would have to take in account other important aspects. These aspects, amongst others, are the individual’s socio-cultural, environmental and social upbringing3.

Through the ages of modern psychiatry, developments in research, which includes in substance related conditions, have led to updates in the DSM (the diagnostic and statistical manual of mental disorder). During the discussions, preparing the DSM 5, it was decided, by the majority, to drop the criminal activity criterion. This was due to the low prevalence rates of criminality in presenting patients. It was advised that it should only be considered in decisions of prescribing treatment options to the few indicated cases4.


The meso-limbic dopamine system, which is a neurotransmitter system, involves signals that run from the VTA (the ventral tegmental area) to the NAC (the nucleus acumens).  The VTA is involved in the communications of information that is important to survival, for example in the response to hunger or pending danger.  The NAC has been indicated in the learning of and the motivation to seek out salient experiences5.   The meso-limbic dopamine system sends communications to the prefrontal cortex to register how rewarding the salient experience was.  In turn this increases the possibility that the salient event would be repeated in the future6.

This system has been indicated to be highly involved in the development of addiction of mind altering substances4.  The hippocampus and amygdala, in the limbic system, have also been indicated to be involved in the storing of information in memory of salient experiences and its emotional counterparts, respectively5.  It is in these parts of the brain when exposed to excessive amounts of dopamine, like in the process of intoxication of substances (e.g. stimulants like methamphetamine), can imitate symptoms (e.g. hallucinations and delusions) found normally in  other disorders (e.g. schizophrenia) 5.

Substances, in different ways according to their characteristics and known features, alter how these brain areas communicate to each other7.  Over time these areas adapt.  Some effects are felt for longer periods even though the substance use is stopped.

When addiction in compared to other chronic relapsable diseases, like diabetes, it can be defined as having a known affected part of the anatomy and therefore, through pharmacological treatments, can be managed8.


With the new dawn of molecular biology it has been able to look at the development of an addiction on a cellular level9.  Within the dopminergic circuits, when exposed to substances, changes are seen in transcription factors of delta FosB and cAMP responsive element binding protein (CREB) 9.   When substances are introduced in the body, dopamine levels escalate which in turn increases the production of cyclic AMP (cAMP) which activates CREB.  Theses levels rise until tolerance is met and stay on a constant level until the user ceases use.  Thereafter the level would decrease6.

However something else is produced at the same time as CREB, delta FosB, which is also a binding protein, once generated does not reduce and stays constant for the user’s lifespan.  This is one of the long term factors that lead to relapse5.



As stated above, genetics play a vital role in the development of addiction3.  Genetics have been indicated to be 40-60% inheritable9.  Evidence collected from twin (monozygotic) and adoption studies where siblings where placed in different social- environmental settings via association and linkage studies, show that environmental factors can influence when a adolescent initiates substance use but when the user later on enters dependence, genetics are more responible5.   Linkage studies have been able to link certain chromosomes to certain substances (e.g. alcohol dependence, Chromosome 11)3.  Association studies have been able to link certain populations to higher risk categories (e.g. Asians and alcohol dependence) 3.  One of the candidate genes in addiction that has been indicated is the dopamine D2 receptor gene (DRD2), which is known to be related to alcohol, stimulant, opioid and other process addictions5.

Future developments in genetic testing, phenotypes could be identified that would allow for interventions (e.g. pharmacological) to be started prior to the exposure to substances5.

Socio-cultural, environmental and learning theory

As seen above, through epigenetic studies when it comes to the initiation of substance use which could lead to a substance use disorder, it is the environment that the individual finds themselves in which contributes to the development of addiction5.  In the above discussions of neurotransmitters and genetic indicators of addiction, majority of the evidence was done in a controlled environment.  An individual’s relationship with substances is shaped by their socio-cultural backgrounds.  These addictive behaviours are learnt10.  If they are learnt they can be unlearnt.

Poverty, poor parenting, limited family support and high levels of adversity have all been linked to the increased the risk of addiction10.

The learning process by modelling peers through classical conditioning, where persons links unconditioned stimulus (the substance) with a neutral stimulus (a substance related external cue- e.g. People/ Places or internal cue- e.g. Hunger/ Fear) to a unconditioned response (e.g. pleasure- euphoria/ relief from pain).  Over time the neutral stimulus, now conditioned, provokes the need to seek out the unconditioned response, now conditioned5.

Another learning process is operant conditioning. This is where a goal directed behaviour has a salient effect (e.g. euphoria from opioid intoxication).  This behaviour is through the before-mentioned VTA-NAC reward pathway, put into memory that it salient and should be repeated.  This is positive reinforcement.  Conversely if a goal directed behaviour is done to reduce e.g. withdrawal symptoms, this would be negative reinforcement.   The speaker of the local forum that stated that “addicts are criminals who deserve to be punished appropriately” would be an example of positive punishment, which is the third type of operant conditioning.


In this brief response to the statement posed.  The various models describing addiction indicates the need for a thorough investigation into the individuals bio-psycho-social background.  Yes, addicts, through the development of addiction, do bad things, but this does not mean that they are bad people1.  However if a practitioner treats addiction as a chronic relaspable disease, the possibility of maintaining recovery is increased8.


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Reference list

  1. Leshner AI. Addiction Is a Brain Disease, and it matters. Journal of Lifelong Learning in Psychiatry 2003; 1(2): 190 – 193 OR Science 1997; 278 (Oct 3): 45-47
  2. Piazza PV, et al. A Multistep general theory of transition to addiction. Psychopharmacology (2013) 229:387–413.  DOI 10.1007/s00213-013-3224-4
  3. Ball D. Genetics of Addiction.  Psychiatry 2006; 5(12): 446-448
  4. Hasin DS, et al. DSM-5 Criteria for Substance Use Disorders: Recommendations and Rationale.  Am J Psychiatry. 2013 August 1; 170(8): 834–851.  DOI:10.1176/appi.ajp.2013.12060782.
  5. World Health Organisation, Geneva. Neuroscience of psychoactive substance use and dependence (2004)
  6. Nester EJ, Malenka RC. The addicted brain.  Scientific American (2004) March: 78-85
  7. Volkow N. Imaging the addicted brain: From Moleclues to Behavior.  Journal of Nuclear Medicine (2004) 45(11): 13N-24N
  8. Day E, et al. Natural history of substance-related problems. Psychiatry 2006; 6(1):12-15
  9. Volkow N et al. Drug addiction: neurobiology of behavior gone awry.  Nature Reviews Neuroscience 2004; 5(12):963-970
  10. Crocq M. Historical and cultural aspects of man’s relationship with addictive drugs.  Dialogues Clin Neursci Dec 2007; 9(4): 355- 36