Behavioural Models and Theories of Drug Addiction – Lecture Review

These flashcards cover key neurotransmitters, reward circuitry, animal models, modern measurement techniques, major psychological and neurobiological theories (incentive sensitisation, habits, hedonic allostasis, frontostriatal dysfunction), DSM criteria, and choice-based perspectives on addiction. They provide a broad yet concise review of the lecture content to aid exam preparation.

Which neurotransmitter released from VTA neurons is critical to the reinforcing effects of drugs of abuse?

Dopamine

What are the two main types of synapses that, respectively, excite and inhibit postsynaptic neurons in reward circuitry?

Glutamatergic (excitatory) and GABAergic (inhibitory) synapses

Approximately what percentage of cancers in Australia are linked to smoking?

20–30%

Which class of drugs accounted for the largest proportion (41%) of drug-related deaths in recent Australian data?

Opioids

In Henningfield’s ratings, which drug is considered the most difficult to quit?

Nicotine

What percentage of cigarette smokers become persistent daily users?

≈90%

What simple Pavlovian task measures whether a rat 'likes' a drug by its preference for a drug-paired chamber?

Conditioned Place Preference (CPP)

Which animal procedure allows rodents voluntary control over drug intake via a jugular catheter?

Intravenous Self-Administration (IVSA)

What technique collects extracellular neurotransmitters through a membrane implanted in the brain of an animal?

Intracranial Microdialysis

Natural rewards elevate nucleus accumbens dopamine to roughly what percentage of baseline in deprived rats?

140–150% of baseline

Drugs of abuse can raise nucleus accumbens dopamine by up to how many times baseline levels?

Up to 10-fold

Fast Scan Cyclic Voltammetry improves on microdialysis by providing much better resolution of what type?

Temporal

d-Light photometry detects dopamine by measuring emitted ___ when genetically encoded sensors bind dopamine.

Fluorescence

Why is the method of drug administration ('master' vs 'yoked') important in animal studies of addiction?

Voluntary (master) intake produces different brain and behavioural outcomes than passive (yoked) intake.

The DSM-V groups substance use and gambling under which disorder category?

Substance-Related and Addictive Disorders

According to 'aberrant learning' theory, drugs of abuse cause enduring changes in circuits normally mediating and __

Learning; memory

In incentive sensitisation theory, 'liking' refers to hedonic impact, whereas 'wanting' refers to ___

Incentive salience or motivational value

Which nucleus accumbens medium spiny neuron subtype (D1 or D2) encodes cue-driven drug associations detected with d-Light photometry?

D1 MSNs

Saunders & Robinson (2010) showed that sign-trackers are highly susceptible to ___-induced relapse.

Cue

In selectively bred rats, which group (bHR or bLR) typically displays sign-tracking behaviour and larger cue-evoked dopamine bursts?

bHR (high responder) rats

Sensitisation to cocaine accelerates the shift from goal-directed action to ___-based responding.

Habit (stimulus–response)

Pelloux et al. showed rats will continue seeking cocaine despite foot-shock after extended training, despite __.

Negative consequences

According to Piazza’s DSM-IV-inspired model, approximately what fraction of rats met all three addiction-like criteria?

17%

Frontostriatal dysfunction theories link reduced striatal D2 receptor availability with hypometabolism in which prefrontal regions (name any two)?

Orbitofrontal cortex, anterior cingulate gyrus, or dorsolateral prefrontal cortex

High impulsivity in rats predicts later ___ cocaine intake on three criteria: motivation, inability to refrain, and persistence despite punishment.

Compulsive

George Koob’s hedonic allostasis model emphasises sensitisation of the brain’s ___ reward systems driving negative affect.

Anti-reward or stress

Which three-stage cycle summarises Koob’s opponent-process model of addiction?

Binge/intoxication → Withdrawal/negative affect → Preoccupation/anticipation

Ettenberg et al. found that cocaine produced conditioned place aversion when conditioning occurred how many minutes post-injection?

15 minutes

Carl Hart argues that roughly what percentage of crack or meth users become addicted?

10–20%

Heyman’s choice theory notes that addiction shows the highest rate among psychiatric disorders.

Remission

Ahmed’s two-lever studies show most rats prefer over cocaine, even after weeks of drug exposure.

Sucrose (or saccharin)

In Ahmed’s work, approximately what percentage of rats persistently choose cocaine over a nondrug reward?

10–20%

Name one argument against equating 'compulsive drug use' solely with 'use despite adverse consequences'.

Such behaviour can arise from factors other than compulsion; compulsion is only one component of addiction; extended intoxication history matters, etc.

Sign-tracking behaviour in animals is conceptually similar to what cue-driven behaviour observed in some humans with addiction?

Attention bias and approach toward drug-related cues

What experimental task classifies rats as sign-trackers or goal-trackers based on lever approach versus magazine approach?

Autoshaping (Pavlovian conditioned approach)

What is the primary neurochemical common endpoint of virtually all drugs of abuse according to microdialysis work?

Excess dopamine in the nucleus accumbens

Which drug of abuse displays reinforcing properties in rats similar to methamphetamine but also shares MDMA-like neurotransmitter release characteristics?

Mephedrone

Which two brain regions were sampled in early microdialysis studies to compare mesolimbic vs nigrostriatal dopamine changes after drug intake?

Nucleus accumbens and dorsal caudate nucleus

According to Solomon’s opponent-process theory, what is the term for the new lowered hedonic 'set point' after chronic drug use?

Hedonic allostasis

In Koob’s framework, which trait dominates early in addiction (impulsivity or compulsivity) and which dominates late?

Impulsivity dominates early; compulsivity dominates late.

What proportion of cocaine-addicted humans typically stop using without professional treatment by age 30, according to epidemiological data?

A majority (>50%)

Conditioned reinforcers maintain drug-seeking even in the absence of the drug. Give an everyday example in humans.

Seeing a cigarette pack triggers craving; seeing a bar triggers alcohol seeking; etc.

What distinguishes a habit from a compulsion in the context of drug addiction?

Habits can revert to goal-directed control; compulsions persist despite adverse consequences and loss of voluntary control.

Name one modern in vivo technique, other than microdialysis, used to measure rapid dopamine changes in freely moving animals.

Fast Scan Cyclic Voltammetry (FSCV) or d-Light photometry

Under Koob’s three-stage cycle, which stage is most associated with negative reinforcement?

Withdrawal/negative affect

Which rodent trait—high locomotor response to novelty (HR) or low (LR)—predicts faster acquisition of cocaine self-administration?

High responder (HR)

Frontostriatal dysfunction theories emphasise inadequate top-down control from which cortical region over striatal pathways?

Prefrontal cortex (including OFC, ACC, dIPFC)

According to Corbit et al. (2014), sensitisation to which drug speeds the development of S-R habits in rats?

Cocaine

Koob’s anti-reward system particularly recruits which stress-related neurochemical systems (name one)?

CRF (corticotropin-releasing factor) or dynorphin

In nicotine studies, pairing nicotine with an aversive outcome (LiCl-induced nausea) eventually becomes ineffective after training.

Extended

What are the three behavioural criteria used in Piazza’s rat model to diagnose addiction-like behaviour?

Persistence in seeking when drug unavailable; resistance to punishment; high motivation (progressive ratio break-point)

Which brain plasticity measure remains impaired only in addiction-vulnerable rats but recovers in non-addicted rats?

Long-term depression (LTD)

Name one of Milton & Everitt’s (2010) three ways incentive stimuli promote relapse.

Attract attention/approach, act as conditioned reinforcer, evoke conditioned motivation/desire

The majority of current therapies for opioid addiction rely on what strategy that can itself perpetuate dependence?

Substitution therapy (e.g., methadone, buprenorphine)

Which DSM-V 'emerging measure' disorder involves problematic engagement with electronic entertainment and is under further study?

Internet gaming disorder

Why is equating addiction solely with 'use despite adverse consequences' potentially harmful, according to recent critiques?

It oversimplifies addiction, ignores heterogeneity, and may misdirect treatment development.

In choice paradigms, rats often forego heroin to spend time with , highlighting social reward’s protective role.

Conspecifics (friends/peers)

Which concept posits that initial drug reward (A-process) is followed by an opposing negative B-process that grows with use?

Opponent-process theory

Drugs like nicotine show high rates of persistent daily use partly because of what pharmacological attribute (rapid onset, metabolism, etc.)?

Rapid brain penetration and short inter-dose intervals sustaining reinforcement

Name two core behavioural components common to most modern theories of addiction.

Compulsive drug seeking/use; continued use despite negative consequences