Substance use and addiction

Question 1

Single Convention on Narcotic Drugs of 1961

Answer 1

• Limit possession, use, trade in, distribution, import, export, manufacture and production of drugs to
  medical and scientific purposes.
• Combat drug trafficking through international cooperation to deter and discourage drug traffickers

Question 2

Convention on Psychotropic Substances 1971

Answer 2

• Responded to the diversification and expansion of the spectrum of drugs (Turn on, tune in, drop out);
• Introduced controls over synthetic drugs and their therapeutic values.

Question 3

Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances
1988

Answer 3

• Really aimed at traffickers;
• Provides international cooperation through extradition, controlled deliveries, transfer of proceedings, etc

Question 4

In Canada, all seized drugs are sent to Health
Canada for analysis by the

Answer 4

Drug Analysis
Service (DAS)

Question 5

defining controlled substances Schedule I

Answer 5

• No accepted medical use;
• Lack of accepted safety for use under medical supervision;
• High potential for “abuse”;
• Heroin, MDMA. (Note: Cannabis was here)

Question 6

defining controlled substances Schedule 2

Answer 6

• High potential for “abuse” which may lead to severe psychological
  and/or physical dependence;
• Opiates: methadone, (Dolophine®, oxycodone (OxyContin®,
  Percocet®), fentanyl (Sublimaze®, Duragesic®), morphine,
  opium, codeine.
• Stimulants: amphetamine (Dexedrine®, Adderall®),
  methamphetamine (Desoxyn®), and methylphenidate (Ritalin®

Question 7

defining controlled substances Schedule 3

Answer 7

• Less potential for ”abuse” than Schedules I or II and use may lead to
  moderate or low physical dependence or high psychological
  dependence;
• Examples: products with <15mg of hydrocodone (Vicodin®),
  products containing <90mg of codeine (Tylenol with Codeine®),
  buprenorphine (Suboxone®), ketamine and anabolic steroids

Question 8

defining controlled substances schedule 4

Answer 8

• Low potential for abuse relative to substances in Schedule III
• Examples: alprazolam (Xanax®), clonazepam (Klonopin®),
  diazepam (Valium®), lorazepam (Ativan®), midazolam (Versed®)
  and triazolam (Halcion®

Question 9

defining controlled substances schedule 5

Answer 9

• Low potential for abuse relative to substances listed
  in Schedule IV and consist primarily of preparations
  containing limited quantities of certain opiates
• Examples: cough preparations containing <200mg of
  codeine per 100mL or 100g
• Examples: Robitussin AC®, Phenegan with Codein®
  and ezogabine.

Question 10

substances that result in euphoria act as positive
reinforcers and can lead to

Answer 10

addiction

Question 11

two major things that makes a substance addictive

Answer 11

euphoric effects and withdrawal symptoms

Question 12

According to Koob & Volkow (2010), addiction
involves a cycle composed of three stages:

Answer 12

1. Binge intoxication – characterized by
   impulsivity;
2. Withdrawal/negative affect – characterized by
   the transition from impulsivity to compulsivity;
3. Preoccupation/anticipation – characterized by
   both impulsivity & compulsivity.

Question 13

The shift from impulsivity to compulsivity coincides
with a shift from

Answer 13

positive reinforcement to
negative reinforcement

Question 14

Olds & Milner, 1954 Discovered

Answer 14

(by accident) neural circuits responsible for biological basis of pleasure in the limbic system;
- Gradually, the anatomical pathways and neurochemical
substances were determined and mapped.

Question 15

Most, if not all, drugs prone to
dependence/addiction share a common
denominator:

Answer 15

the dopaminergic system
plays a central role in reward and
reinforcement

Question 16

the mesolimbic and
mesocortical dopaminergic pathways mediate:

Answer 16

These pathways mediate the rewarding
and reinforcing effects of natural
rewards (and drugs)

Question 17

The .. is responsible for
pleasure/euphoria and is critical to the development of addiction.

Answer 17

Nucleus Accumbens (NAc or NAcc)

Question 18

Major NAc inputs:

Answer 18

• Prefrontal association cortices;
• Basolateral amygdala;
• Ventral Tegmental Area (VTA, A10);
• CA1 region of hippocampus (remember LTP!)

Question 19

Major NAc outputs:

Answer 19

• Basal ganglia, ventral globus pallidus (impulsivity!);
• VTA, Substantia Nigra, Reticular Formation;

Question 20

NAc is subdivided into two anatomically and functionally distinct regions:

Answer 20

1. Shell
   - Receives input from BLA and ventral subiculum (major
   output from hippocampus);
   - Considered “extended amygdala”;
2. Core
   - Inputs from BLA and parahippocampal regions

Question 21

The… is a large collection of
ascending and descending
pathways

Answer 21

Medial Forebrain Bundle
(MFB)

Question 22

The … is also very important for the pleasure/reward associated with drug use, as it
mediates the emotional characteristics of drug use

Answer 22

amygdala

Question 23

The ….. records memories of
experiences with drug use. Heavily involved in conditioned place preference, anticipation of drug use, and relapse

Answer 23

hippocampus

Question 24

Withdrawal from drugs typically elicits symptoms
characterized by:

Answer 24

irritability, anxiety and depression

Question 25

The neuroadaptations can be divided into two
progressive processes

Answer 25

1. Within-system adaptation;
2. Between-systems adaptation

Question 26

Within-System Adaptions:

Answer 26

• Direct attempt by the brain to counteract the repeated drug-
  induced activation of that circuit;
• Cells will start pulling receptors from the membrane,
  releasing retroactive transmitters to slow neurotransmitter
  release, etc

Question 27

Between Systems Adaptations:

Answer 27

• Gradual recruitment of the anti-reward system;
• Neuroanatomical make up of the anti-reward system is the
  extended amygdala (i.e. bed nucleus of the stria terminalis,
  central nucleus of the amygdala, nucleus accumbens shell)
• Norepinephrine, corticotropin-releasing factor (CRF) and
  dynorphin are the main transmitters involved in this system;
• Naturally, this system is in place to inhibit the reward system
  and mediate aversive effects of stress

Question 28

Opponent Process Model:

Answer 28

• Any stimulus that provokes a
  strong affective reaction
  (pleasure or discomfort),
  automatically sets in motion
  an opposing affective
  response that is experienced
  after the initial stimulus
  ends.
• Allostatic changes gradually
  shift the hedonic setpoint.

Question 29

The preoccupation/anticipation stage of addiction
involves …. of the prefrontal cortex

Answer 29

dysregulation