NR 546 WEEK 6 STUDY
GUIDE — ADDICTION,
REWARD CIRCUITS,
MAT, SUDS (ULTIMATE
GUIDE FOR 2026/2027
Study Ace Smart
,WEEK 6 STUDY GUIDE — Addiction,
Reward Circuits, MAT, SUDs
1. Reward Circuits & Neurobiology of
Addiction
Key Brain Regions
• Ventral tegmental area (VTA) → dopamine release.
• Nucleus accumbens (NAc) → reward “pleasure center.” Prefrontal cortex
(PFC) → decision-making, impulse control.
• Amygdala → conditioned cues, emotional memory.
• Hippocampus → contextual memory related to substance use.
Neurotransmitters
• Dopamine → primary mediator of reward, reinforcement.
• GABA → impacted by alcohol, benzos, barbiturates.
• Glutamate → craving, learning pathways.
• Endogenous opioids → euphoria/pain relief.
• Serotonin → impulsivity, mood regulation.
• Acetylcholine (nicotinic receptors) → nicotine addiction.
Natural vs. Substance-Induced Highs
• Natural rewards (food, sex) cause moderate dopamine release.
• Substances cause rapid, supraphysiologic dopamine spikes → reinforcement
→ rewiring of reward circuitry.
, 2. Impulsivity vs. Compulsivity (Stahl Ch.
13)
Impulsivity Compulsivity
Acting without thinking, “quick reward” Repetitive behaviors to reduce anxiety
Linked to dopamine surges Linked to serotonin/glutamate dysregulation
Seen in: early drug use, ADHD, maniaSeen in: OCD, addiction maintenance phase
Reward-seeking Anxiety-reducing
Substance use starts with impulsivity, becomes compulsive as brain circuits
adapt.
3. substance use disorders & Clinical Clues
Opioids
• MOA: Mu opioid receptor agonists.
• Intoxication: Miosis (pinpoint pupils), respiratory depression, bradycardia,
constipation.
• Withdrawal: Dilated pupils, lacrimation, yawning, diarrhea, piloerection
(“cold turkey”), rhinorrhea, mydriasis.
Stimulants (cocaine, amphetamines)
Intoxication: Mydriasis, sweating, tachycardia, chest pain, elevated BP,
psychosis. Withdrawal: Depression, hypersomnia, fatigue, increased
appetite.
Nicotine
• MOA: Nicotinic acetylcholine receptor agonist.
• Withdrawal: Irritability, cravings, anxiety, increased appetite.
Alcohol
• Intoxication: Slurred speech, ataxia, nystagmus.
GUIDE — ADDICTION,
REWARD CIRCUITS,
MAT, SUDS (ULTIMATE
GUIDE FOR 2026/2027
Study Ace Smart
,WEEK 6 STUDY GUIDE — Addiction,
Reward Circuits, MAT, SUDs
1. Reward Circuits & Neurobiology of
Addiction
Key Brain Regions
• Ventral tegmental area (VTA) → dopamine release.
• Nucleus accumbens (NAc) → reward “pleasure center.” Prefrontal cortex
(PFC) → decision-making, impulse control.
• Amygdala → conditioned cues, emotional memory.
• Hippocampus → contextual memory related to substance use.
Neurotransmitters
• Dopamine → primary mediator of reward, reinforcement.
• GABA → impacted by alcohol, benzos, barbiturates.
• Glutamate → craving, learning pathways.
• Endogenous opioids → euphoria/pain relief.
• Serotonin → impulsivity, mood regulation.
• Acetylcholine (nicotinic receptors) → nicotine addiction.
Natural vs. Substance-Induced Highs
• Natural rewards (food, sex) cause moderate dopamine release.
• Substances cause rapid, supraphysiologic dopamine spikes → reinforcement
→ rewiring of reward circuitry.
, 2. Impulsivity vs. Compulsivity (Stahl Ch.
13)
Impulsivity Compulsivity
Acting without thinking, “quick reward” Repetitive behaviors to reduce anxiety
Linked to dopamine surges Linked to serotonin/glutamate dysregulation
Seen in: early drug use, ADHD, maniaSeen in: OCD, addiction maintenance phase
Reward-seeking Anxiety-reducing
Substance use starts with impulsivity, becomes compulsive as brain circuits
adapt.
3. substance use disorders & Clinical Clues
Opioids
• MOA: Mu opioid receptor agonists.
• Intoxication: Miosis (pinpoint pupils), respiratory depression, bradycardia,
constipation.
• Withdrawal: Dilated pupils, lacrimation, yawning, diarrhea, piloerection
(“cold turkey”), rhinorrhea, mydriasis.
Stimulants (cocaine, amphetamines)
Intoxication: Mydriasis, sweating, tachycardia, chest pain, elevated BP,
psychosis. Withdrawal: Depression, hypersomnia, fatigue, increased
appetite.
Nicotine
• MOA: Nicotinic acetylcholine receptor agonist.
• Withdrawal: Irritability, cravings, anxiety, increased appetite.
Alcohol
• Intoxication: Slurred speech, ataxia, nystagmus.
