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PSY3190: Addiction Studies
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Table of Contents
Defining Addiction ...................................................................................................................................................... 8
What is a drug? ......................................................................................................................................................... 8
Harms Associated with Psychoactive Drugs .......................................................................................................... 8
Key DSM Definitions ................................................................................................................................................ 8
Key ICD-10 Definitions .............................................................................................................................................. 9
Classifications of Psychoactive Drugs ..................................................................................................................... 9
Drug Policy .................................................................................................................................................................. 10
What is ‘Drug Policy’? .............................................................................................................................................. 10
Policy Levers ........................................................................................................................................................... 10
Challenges of Drug Policy ....................................................................................................................................... 10
Types of Policy Approaches ................................................................................................................................... 10
War on Drugs vs. Harm Minimisation .................................................................................................................... 12
The National Drug Strategy: Australia’s Current Approach .................................................................................. 13
The Policy Cycle ....................................................................................................................................................... 14
Why Study Pharmacology? ........................................................................................................................................ 15
Assisting Knowledge .............................................................................................................................................. 15
Factors Affect Drug Absorption ............................................................................................................................. 15
Psychopharmacology Overview ............................................................................................................................... 16
Pharmacokinetics vs. Pharmacodynamics ............................................................................................................. 16
Pharmacokinetics ....................................................................................................................................................... 16
Processes ................................................................................................................................................................ 16
1. Modes of Administration .............................................................................................................................. 17
2. Absorption ..................................................................................................................................................... 17
3. Distribution .................................................................................................................................................... 17
4. Metabolism .................................................................................................................................................... 18
5. Excretion ........................................................................................................................................................ 18
Pharmacodynamics ................................................................................................................................................... 20
Elements ................................................................................................................................................................. 20
Drug Interaction ..................................................................................................................................................... 20
Agonist v Antagonist ............................................................................................................................................. 20
Reinforcement ........................................................................................................................................................ 21
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Tolerance ................................................................................................................................................................. 22
Drug Dependence ................................................................................................................................................... 22
Withdrawal .............................................................................................................................................................. 22
Drug Interactions .................................................................................................................................................... 22
Antagonism ............................................................................................................................................................. 22
Evolution of Reinforcement & Drugs ....................................................................................................................... 23
What is reinforcement? .......................................................................................................................................... 23
Evolutionary Purposes of Reinforcement .............................................................................................................24
Brain Structures & Neural Pathways of Reward ..................................................................................................... 24
Beginnings of Structure ..........................................................................................................................................24
The Brain’s “Pleasure Centre”: Mesolimbic Dopamine Pathway ........................................................................ 26
Structures and Neurotransmitters Together ....................................................................................................... 26
The Role of Endorphins .......................................................................................................................................... 27
Maladaptive Changes in Drug Circuitry ................................................................................................................... 28
Neurotransmitter Defects ..................................................................................................................................... 28
‘Hijacking’ Reward Circuity .................................................................................................................................... 28
Biological Basis of Addiction .................................................................................................................................... 30
Biological Theories of Drug Addiction .................................................................................................................. 30
1. Incentive Desensitisation ............................................................................................................................. 30
2. Genetic Theories ............................................................................................................................................ 31
3. Neurocognitive Studies ................................................................................................................................. 35
4. Decision Making Studies .............................................................................................................................. 36
5. Addiction: A Developmental Disorder? ......................................................................................................... 37
Psychological Aspects in Current Systems ...............................................................................................................39
Symptoms of Abuse and Dependence ................................................................................................................. 39
The Role of Adolescence........................................................................................................................................... 40
Developmental Model of Addiction ...................................................................................................................... 40
Main Theories of Behavioural Change (Readings) .................................................................................................. 41
Behavioural Theories of Addiction .......................................................................................................................... 43
Overview ................................................................................................................................................................ 43
Conditioning Theories ........................................................................................................................................... 43
Cognitive Theories of Addiction............................................................................................................................... 45
Overview ................................................................................................................................................................ 45
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Cognitions Relating to Substance Use.................................................................................................................. 45
Cognitive Model of Substance Abuse (Beck) ....................................................................................................... 45
Social Cognitive Theory (Bandura) ....................................................................................................................... 46
Personality Theories of Addiction............................................................................................................................ 49
Overview ................................................................................................................................................................ 49
Two Dimensions ..................................................................................................................................................... 50
Integrative Model I: Transition from impulsivity to compulsivity ......................................................................... 50
Impulsivity � Compulsivity (Animal Models) ...................................................................................................... 50
Transition from Impulsivity � Compulsivity (Human Models) ............................................................................ 51
Neuropsychology: Assessment of behavioural consequences of brain systems dysfunction ........................... 51
Perseveration-Compulsivity: Probabilistic Reversal .............................................................................................. 52
Transition Vulnerability to Dependence ................................................................................................................ 53
Integrative Model II: Emotion, Interoception and Decision-Making ..................................................................... 54
Somatic Marker Model .......................................................................................................................................... 54
Interoceptive Awareness ...................................................................................................................................... 54
Understanding Addiction and Consequences .......................................................................................................... 55
General View ........................................................................................................................................................... 55
Defining Addiction in Social Contexts .................................................................................................................... 55
Overview of Theories of Drug Use and Addiction .................................................................................................. 56
Liberal Models ......................................................................................................................................................... 57
Disease Models ....................................................................................................................................................... 57
Self-Medication Hypothesis ................................................................................................................................... 57
Historical Views of Addiction ................................................................................................................................ 58
Social Theories ...........................................................................................................................................................59
Social Drivers of Addiction .................................................................................................................................... 59
Hovarth: Social Learning Theory of Addiction ..................................................................................................... 59
Zinberg’s Theory of Drug Addiction (Drug, Set, Setting) .................................................................................... 60
Drug Using Identities ............................................................................................................................................. 62
Parker: Culture and Normalisation ....................................................................................................................... 62
Stigmatisation v. Normalisation ............................................................................................................................ 64
Case Study: Is Addiction A Brain Disease? ............................................................................................................... 65
Neuroscience Evidence for the “Brain Disease Model” ...................................................................................... 65
Limitations of Neuroscience Evidence .................................................................................................................. 66
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Social Science Evidence for the “Brain Disease Model” ...................................................................................... 66
Policy and the “Brain Disease Model” .................................................................................................................. 67
Industry the “Brain Disease Model” ..................................................................................................................... 68
Direct Treatment of the Addicted Brain .................................................................................................................. 69
Ablative Neurosurgery (Eg. For Heroin Addiction) .............................................................................................. 69
Deep Brain Stimulation .......................................................................................................................................... 69
Medicalisation of Addiction ...................................................................................................................................... 71
Impact of Brain Disease Explanations on Treatment ............................................................................................ 71
Views of Addicted Individuals ................................................................................................................................ 71
Neurobiology and Policy ........................................................................................................................................ 72
Summary of Social Theories ...................................................................................................................................... 72
Epidemiology .............................................................................................................................................................. 73
Forms of Problem Gambling .................................................................................................................................. 73
DSM V and Problem Gambling .............................................................................................................................. 74
Current Integrative Models of Problem Gambling .................................................................................................. 75
Biopsychosocial Model ........................................................................................................................................... 75
Pathways Model ..................................................................................................................................................... 75
Issues with Existing Models ................................................................................................................................... 75
Heterogeneity of Gambling Forms ....................................................................................................................... 76
Individual Differences in Problem Gambling ........................................................................................................... 77
Genetics/Heritability ............................................................................................................................................... 77
Personality ............................................................................................................................................................. 78
Reward/Punishment .............................................................................................................................................. 79
Cognitive Variables ................................................................................................................................................ 79
Risk Factors for Maintenance of Problem Gambling ........................................................................................... 79
Brain Functioning ................................................................................................................................................... 80
Neurobiological Models of Problem Gambling & Addiction .................................................................................. 80
Stress Model of Addiction ...................................................................................................................................... 81
Ventral to Dorsal Shift ........................................................................................................................................... 82
I-RISA Model .......................................................................................................................................................... 84
Neuroscience Evidence ............................................................................................................................................. 86
Brain Activity After Winning v. Losing .................................................................................................................. 86
Diminished Sensitivity to Losses ........................................................................................................................... 87
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Cue Reactivity in Problem Gambling ..................................................................................................................... 88
Interpreting Gambling Brain Research .................................................................................................................... 89
Key Themes: Neuroscience Findings .................................................................................................................... 89
Neuroscience Based Treatment? .......................................................................................................................... 90
Policy to Reduce Gambling ....................................................................................................................................... 90
Conflicts of Interest ............................................................................................................................................... 90
Policy and Neuroscience......................................................................................................................................... 91
Evidence-Based Policy Decisions ........................................................................................................................... 92
Problem Gambling Summary ................................................................................................................................... 92
Vulnerable Populations ..............................................................................................................................................93
Women ........................................................................................................................................................................93
Why separate women? .......................................................................................................................................... 93
Issues Women Face ............................................................................................................................................... 93
Hidden Drug Use .......................................................................................................................... 93
Women and the Actions of Alcohol ............................................................................................. 94
Women and Illicit Drug Use .......................................................................................................... 94
Pregnancy .................................................................................................................................... 94
Marital Status ............................................................................................................................... 95
Children ........................................................................................................................................ 95
Access to Treatment .................................................................................................................... 95
Violence ........................................................................................................................................ 96
Prostitution .................................................................................................................................. 96
Health Risks for Women ........................................................................................................................................ 96
Menstrual Irregularities ................................................................................................................ 96
Pregnancy and Breastfeeding Issues ........................................................................................... 97
Suicide and Mental Health ........................................................................................................... 98
Elderly People ............................................................................................................................................................ 98
Prevalence .............................................................................................................................................................. 98
Tobacco ........................................................................................................................................ 98
Alcohol ......................................................................................................................................... 99
Prescribed Medications ................................................................................................................ 99
Illicit Drug Use .............................................................................................................................. 99
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Assessment ............................................................................................................................................................ 99
Treatment ............................................................................................................................................................. 100
Smoking Treatment .................................................................................................................... 100
Alcohol ........................................................................................................................................ 100
Benzodiazepines .......................................................................................................................... 101
Aboriginal and Torres Strait Islanders .................................................................................................................... 102
Patterns of Use ..................................................................................................................................................... 102
Alcohol Usage ............................................................................................................................. 102
Illicit Drug Usage Patterns ........................................................................................................... 102
Injecting Drug Usage Pattern ...................................................................................................... 103
Inhalant Usage Patterns .............................................................................................................. 104
Issues for ATSIs ..................................................................................................................................................... 104
Unemployment ........................................................................................................................... 104
Education .................................................................................................................................... 104
Social and Emotional Wellbeing .................................................................................................. 105
Harms .......................................................................................................................................... 106
Theoretical Perspectives on Use .......................................................................................................................... 106
Historical Perspective .................................................................................................................. 106
Anthropological Perspective ....................................................................................................... 106
Physiological Perspective ............................................................................................................ 107
Psychosocial Perspective ............................................................................................................ 107
Interventions ......................................................................................................................................................... 107
Components of Effective Treatment .......................................................................................... 108
Community Approaches .............................................................................................................. 108
Theories of Aetiology of Coexisting Disorders ...................................................................................................... 109
Key Principles of Treatment ..................................................................................................................................110
Biological Influences on Risk of Addiction .............................................................................................................. 110
Genes ......................................................................................................................................................................110
Maturational Stages .............................................................................................................................................. 112
Neurodevelopmental disorders (e.g. ADHD) ....................................................................................................... 112
Psychological Influences on Risk of Addiction ........................................................................................................ 113
Emotion Recognition � Social Cognition Deficits ............................................................................................... 114
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Personality Disorder Types .................................................................................................................................... 114
Reappraisal Tasks: Emotion Regulation Difficulties in Addiction ........................................................................ 115
Social Influences on Risk of Addiction ..................................................................................................................... 115
Prevention in Adolescents ........................................................................................................................................ 116
16 Principles of Effective Prevention in Adolescents ...........................................................................................116
Early Intervention Hotspots ..................................................................................................................................119
Harm Reduction .....................................................................................................................................................119
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Week One: Defining Addiction & Drug Policy
Defining Addiction
What is a drug? ► WHO: A drug is a chemical entity used non-medically, self-administered for its psychoactive
effect.
▫ Other definitions may include:
� Any substance that alters our physiology, mood, cognition or behaviour but
does not constitute food or nutrient.
� Any substance taken with the intent to alter mood, cognition or behaviour.
▫ Psychoactive substances are drugs that have cognitive and/or behavioural effects.
Harms Associated with Psychoactive Drugs ► Toxicity (Intoxication)
▫ Usually an immediate effect of the drug, when the blood level concentration rises
rapidly.
▫ Alcohol is high toxicity.
▫ Cannabis is generally low in toxicity, but depending on the route of administration
(eating vs. smoking), it may exit faster into the bloodstream and therefore, by
definition, more intoxicating.
► Dependence
▫ A delayed effect and potentially long-lasting.
▫ Addiction potential.
▫ Seen in heroin, methamphetamines, nicotine.
Key DSM Definitions ► Substance Abuse: self-administration of psychoactive substance.
► Substance-Related Disorders: usage pattern that meets DSM criteria (allow for subtyping
based on a continuum from mild to severe.
▫ Withdrawal: negative reactions generated by body/brain in absence of the substance:
psychological and physiological issues (eg. Insomnia, anger)
▫ Tolerance
� Feel the effects less, may started using higher doses.
▫ Significant time spent in activities to obtain/use, interfere with normal activities
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▫ Craving: arousal, desire, conflict from strong desire to use the substance.
Key ICD-10 Definitions ► Associated with harmful use, not abuse.
► Need to have three or more of the following during the past year:
▫ A strong desire or sense of compulsion to take the substance
▫ Difficulties in controlling substance-taking behaviour in terms of its onset,
termination, or levels of use
▫ A physiological withdrawal state when substance use has ceased or has been
reduced, evident from:
� The characteristic withdrawal syndrome for the substance; or use of the
same (or closely related) substance with the intention of relieving or
avoiding withdrawal symptoms
▫ Evidence of tolerance, such that increased doses of the psychoactive substance are
required in order to achieve effects originally produced by lower doses
▫ Progressive neglect of alternative pleasures or interests because of psychoactive
substance use, increases in the amount of time necessary to obtain or take the
substance or to recover from its effects
▫ Persisting with substance use despite clear evidence of overtly harmful
consequences, such as harm to the liver through excessive drinking, depressive
mood states consequent to periods of heavy substance use, or drug-related
impairment of cognitive functioning
Classifications of Psychoactive Drugs ► Generally split into three categories.
▫ Depressants: Suppress, inhibit or reduce CNS activity
▫ Stimulants: Increase activity in the CNS
▫ Hallucinogens: Alter perceptions, thinking, feeling, sense of time and place
▫ Note, Narcotics: Sleep-inducing substances
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Drug Policy
What is ‘Drug Policy’? ► Refers to the intentions and actions of governments in relation to the control of drug
addiction.
► Dynamic concept: as much about process as outcomes.
► Can involve:
▫ Programs to prevent the uptake of drugs
▫ Health and social service programs to assist users and minimise their consequences
▫ Laws and regulations to control supply.
► Involves all levels of government:
▫ Federal: Overarching agenda-setting and documenting the strategic intent for
implementation through agencies
▫ State: Mostly implement drug policies
► Underpinned By harm minimization.
▫ Seeks balance between supply reduction, demand reduction and harm reduction.
Policy Levers ► Government responses to drug use and related harms.
► May be through:
▫ Policy through advocacy: educating/persuading
▫ Policy through network: leveraging relationships within and across governments and
partners.
▫ Policy through money: using spending and taxing powers
▫ Policy through direct government action: delivering services through public agencies
▫ Policy through law: legislation, regulation and official authority
Challenges of Drug Policy ► Conflicting goals (eg. Ambulance v. police intervention)
► Coordination and communication across government portfolios (eg. Police and health)
► Balance (most appropriate mix of policy options)
► Politics
Types of Policy Approaches ► From zero tolerance to harm reduction.
► Multifaceted approach: mix of policy interventions.
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Policy Option Features Examples
Total Prohibition
► Make drug use criminal.
► Allocation of resources.
► Medical response is the prevention of additional health complications.
► Prohibition Era o Results in illegal
importation, unknown content/purity of substances and a black market thriving on exorbitant prices.
► Overall, not cost effective
Partial Prohibition
► Possession of small quantities not prosecuted.
► Production and distribution of large quantities is prohibited.
► Different treatment of substances (classes) and amounts of those substances.
► Cost-ineffectiveness impact of prohibition is acknowledged.
Decriminalisation
► Removes criminal component of drug use.
► Remove or modify penalties.
► Change in enforcement of penalties.
► Netherlands ► Australia: possession of small
amounts of cannabis subjected to fine (SA, ACT, NT, WA, VIC)
Controlled Availability
► Substances are available in known doses nd purity.
► Heroin prescription programs in UK, Switzerland and Spain.
► Switzerland: o Established a ‘needlepark’
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Policy Option Features Examples
Controlled Availability
► These substances are regulated.
► Aims: ► To provide
information nd education to drug users.
► Profit taken out of the black market.
► Provision of substances is taxed which pays of the system and reduces law enforcement costs.
o Established heroin trials in 1994 with methadone, showed improve psychological and physical functioning, OD rate halved.
► Netherlands: o Prescription heroin trials
were very successful... o Methadone alone showed
32% improvement, but deterioration was seen across all areas of functioning after 2 months
Uncontrolled Availability
► Lifting all controls on illicit drugs.
► Not implemented anywhere in the world; not supported by most drug law reform advocates who support control on marketing, production and distribution.
► Unlikely to ever gain widespread community support.
► Uruguay o The Uruguayan Congress
has voted to legalise marijuana.
o This makes Uruguay the first country in the world where it’s legal to grow, sell and consume the drug.
o Those in favour of legalizing marijuana will reduce the power of the drug cartels but those against warn the country will be in “complete contravention” to provisions of International Drug Treaties they are party to
War on Drugs vs. Harm Minimisation ► War on Drugs (history of U.S. policy) vs. Harm Minimisation (History of AU Policy)
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► Drugs in US a major issue, a war on drugs was proposed by Nixon in response to a high rate of
heroin use in Vietnam.
▫ Policy 0f prohibition
► Whereas in the harm minimisation approach:
▫ Acknowledge drug use has always existed and will continue to exist
▫ Completely eradicating drug use is impossible
▫ Continued focus on eradicating drug problems may result in more harm for society
▫ Overall, harm minimisation aims to decrease the harm associated with drug use,
rather than preventing drug use altogether
► Harm Minimisation and the Law Enforcement
▫ Traditionally law enforcement has taken a supply reduction approach
▫ Law enforcement can also contribute to demand reduction and harm reduction by:
▫ Improving links between police & treatment services
▫ Introducing cautioning & diversion schemes
▫ Changing legal status of drug or policing attitudes & behaviour (e.g. cannabis)
▫ Supporting other harm reduction strategies (e.g. needle exchange)
The National Drug Strategy: Australia’s Current Approach ► Objectives
▫ Minimise the level of illness, disease, injury and premature death associated with the
use of alcohol, tobacco, pharmaceutical and illicit drugs;
▫ Minimise the level and impact of criminal drug offences and other drug-related crime,
violence and antisocial behaviour within the community;
▫ Minimise the level of personal and social disruption, loss of quality of life, loss of
productivity and other economic costs associated with the inappropriate use of
alcohol and other drugs; and
▫ Prevent the spread of hepatitis, HIV/AIDS and other infectious diseases associated
with the unsafe injection of illicit drugs.
► Outcomes?
▫ Assessment of the National Drug Strategy 2001
� International attention and acclaim
� Recognises the complexity of drug use issues
� Shared decision making
� Promotion of partnerships
� A balanced approach
� Sound research infrastructure
� Recommendations have been followed up