Addiction

Question 1

Define addiciton.

Answer 1

Pursue relief/reward from substance/drug use.

Question 2

What brain area is implicated in the intoxication stage?

Answer 2

Nucleus accumbens

Question 3

What is drug addiction characterised by?

Answer 3

• Compulsion to seek and take drug
• Loss of control in limiting intake
• Emergence of negative emotional state when denied access to drug

Question 4

What are the two types of motivational framework in addiciton? Describe them.

Answer 4

• Impulse control: positive reinforcement. Pleasure/relief after, tension/arousal before.
• Compulsive disorder: negative reinforcement. Relief after, anxiety/stress before. Persistent and repetitive without reward.

Question 5

What are the 3 stages of the addiction cycle?

Answer 5

1. Binge/intoxication
2. Withdrawal/negative affect
3. Preoccupation/anticipation/craving

Question 6

When does substance dependence begin?

Answer 6

When negative reinforcement overtakes positive reinforcement.

Question 7

What brain areas are implicated in the preoccupation stage of addiction?

Answer 7

• Amygdala: reinforcement learning
• Hippocampus: environmental trigger cues
• PFC: Lack of cognitive control
• Cingulate cortices and temporal lobe: Feeling/craving

Question 8

What happens to the stress response system in addicts?

Answer 8

• Stress response system is unbalanced
• Body attempts to go back to equilibrium
• Within systems: neural adaptation - threshold for reward increases, become demotivated and depressed
• Between systems: Cortisol released when take drug - stress hormones still in system when drug wears off. Hypothalamic-Pituitary-Adrenal Axis. Modulation of amygdala activity.

Question 9

What is a risk factor for addiction?

Answer 9

Stress response genes

Question 10

What personality traits are linked to addiction?

Answer 10

• Impulsivity
• Risk-taking
• Stress responsivity

Question 11

What (drug) treatments are available?

Answer 11

• GABAb receptor antagonists: lower reinforcing effects of some drugs. Modulate dopamine transmission
• Opioid receptor antagonists: bind to opioid receptors and block intake
• Opioid Agonists: bind to receptors and exert similar effects to drug, reduce withdrawal symptoms
• Alpha 2 adrenergic agents: decrease anxiety during withdrawal

Question 12

Describe detoxification

Answer 12

• Abrupt termination of drug use.
• Shortens withdrawal process but increases experience of pain
• Can use tapering instead: slowly decrease

Question 13

What did Luigjes et al. 2012 use as a treatment?

Answer 13

• DBS in nucleus accumbens and medial PFC

- Neural pathways seem to be better targets

Question 14

What did Koob and Volkow (2009) find about the transition to addiction stage?

Answer 14

Neuroplasticity involved to cause changes in mesolimbic dopamine system