operant drug self-administration model

Question 1

What condition is the Operant Drug Self-Administration model used for?

Answer 1

Addiction

Question 2

What does the Operant Drug self-administration model study?

Answer 2

• brian mechanisms and neurobiology of addiction behaviours
• Motivational + behavioural aspects of drug taking
• how cocaine, heroin and nicotine affect brain’s reward system

Question 3

How does the operant drug-self administration model work?

Answer 3

• Rats learn how to self administer drug by pressing lever
• Small tube in vein > near immdiate effect of drug
• Different schedules assess slightly differnt things

Question 4

What is the operant drug self-administration model useful for?

Answer 4

• testing treatments that may reduce drug seeking

Question 5

What does the operant drug self-administration model help us understand?

Answer 5

• neurobiological/chemical basis of addiction behaviours

Stages of addiction
* Initial use and reinforcement
* Escalation -> increase use over time seen in both aniamls and humans
* Withdrawal
* Relapse

Question 6

What is central to the operant drug self-administration model?

Answer 6

Reinforcement
* behaviour strengthened by result of that behaviour
* activates reward circuitry in brain

Question 7

What purpose different schedules in the operant drug self-adminisrtation model serve?

Answer 7

Fixed ratio:
* drug devlivery every time after fixed number of responses
* used to understand transition from controlled drug use to uncontrolled/impulsive use
FR1 schedule:
* behavioural requirement to recieve dose increase each time
* assesses motivational status

Question 8

What is the “break point” in the operant drug self-administration model?

Answer 8

Maximum presses of lever until non-responding

Question 9

What is the strength of face validity in the operant drug self-administration model?

Answer 9

1. Highest
   * level press directly indicative of the reinforced behaviour through unambiguous rewarding effects

Question 10

What is the strength of construct validity in the operant drug self-administration model?

Answer 10

3.Strong
* strong transltion to human features

Question 11

What is the strength of predictive validity in the operant drug self-administration model?

Answer 11

2.Very strong
* strong translation to human situation/treatment

Question 12

What are the face validity features of the operant drug self-administration model?

Answer 12

Human addiction patterns displayed:
* cravings
* relapse
* compulsive use

Vulnerability to drug use is modeled

Question 13

What are the construct validity features of the operant drug self-administration model?

Answer 13

• Engages mesolimbic dopamine system, one of the brains reward pathways central to human addiction
• becomes less sensitive to doapmine when addicted > decrease in brain’s reward fucntion during withdrawal
• studies underpinnings of risk of long-term relapse
• reveals which behaviours/motivations become controlled by abused drug

Question 14

What are the predictive validity features of the operant drug self-administration model?

Answer 14

• Same drugs self-administered abused in people
• translatable effective treatments that reduce self=administration
• pharmacological opioid-receptor blockade reduced alcohol consumption across various rats/mice > in humans opioid receptor blocker naimefene also reduces alcohol consumption

Question 15

What are the two types of operant drug self-administration models and what do they help study?

Answer 15

Individual symptoms: - higher Construct valdiity
* Specific neurobiological/psychological features
* delineating neurobiological mechanisms

Several symptoms: - higher Predictive valditiy:
* pathology of addiction in humans (e.g. DSM presentation)
* testing pharmacological treaments
* conducting lognitudinal behaviour studies where multiple symptoms interact

Question 16

What are the strengths of the operant drug self-administration model?

Answer 16

• can study impulsivity and stress contributions to addiction vulnerability

Question 17

What are the limitations of the operant drug self-administration model?

Answer 17

• Harder to test socially contributing factors (party culture) -> has limited translatbility to successful clinicla treatments
• addiction + vulnerability not one size fits all

Question 18

What are some suggestions for the operant drug self-administration model?

Answer 18

• Test braoder scope of drugs - newer, other abused substances, other opiates/opioids
• look more into hereditary suceptibility
• study with conditions that icnrease drug abuse risk - ADHD/ASD, PTSD
• combine with other models (e.g. LBNM) to study more environmental factors e.g. socioeconomic

Incorporate social factors > CRA (community reinforcement approach) -> substitute drug use with positive social reinforcers (operant conditioning)
* family suppory example in humans
* food example in rats and monkeys -> shows supression of cravings and voluntary abstinance

Gendered studies:
* Male and female rats show similar results but majority of studies are conducted on male rate, would be good to balance the playing field