Substance-related disorders

Question 1

Drugs

Answer 1

o A drug is any substance – solid, liquid, or gas – that brings about physical and/or psychological changes
 Excludes food/water
o Generic “addiction” influences and substance specific influences and effects

Question 2

Three main types

Answer 2

Stimulants
Depressants
Hallucinogens

Question 3

Stimulants

Answer 3

 Speed up the CNS and the messages going between brain and body
 Include
• Caffeine, nicotine, ephedrine, amphetamines (including speed and ice), cocaine, and ecstasy
 Effects include:
• Excitement/euphoria -> anxiety anger/panic
• Tremor, tension, sleeplessness -> psychosis, convulsions/death

Question 4

Depressants

Answer 4

 Slow down CNS and brain-body messages
 Include
• Alcohol, benzo’s, cannabis, opiods (heroin, methadone, codeine, morphine, and pethidine)
 Effects include:
• Relaxation, reduced inhibition -> drowsiness, anaesthesia
• Slow reflexes, relaxation -> respiratory suppression, coma

Question 5

Hallucinogens

Answer 5

 Distort a person’s perception of reality, time and space
 Include
• LSD, psilocybin (magic mushrooms), mescaline, PCP
 Low doses
• Mainly perceptual distortions in space, time, imagery
 Higher doses
• Irrational behaviour, anxiety, depression, psychosis

Question 6

Tolerance

Answer 6

 Decreasing effect from a substance following repeated administration

Question 7

Cross-tolerance

Answer 7

 Tolerance to one substance results in increased tolerance for a related substance

Question 8

Withdrawal

Answer 8

 Series of signs and symptoms resulting from elimination of a substance from the body

Question 9

Intoxication

Answer 9

 Acute effects of a specific substance generally reversible and short term

Question 10

Abuse

Answer 10

 Maladaptive pattern of substance use resulting in impairment or distress

Question 11

Dependence

Answer 11

 Continued use of substance despite obvious problems

 Generally involves physical effects such as tolerance, withdrawal

Question 12

Substance use disorder

Answer 12

o Repeated, recurrent use despite impact on work, social life, and/or physical danger
o Psycho=physiological effects such as withdrawal syndrome, tolerance, craving
o Loss of control over substance use – e.g. failed attempts to stop or cut down, giving up things to use or obtain substance, using more than intended

Question 13

Drug use in Australia

Answer 13

o	Most common – alcohol
o	Followed by tobacco, cannabis
o	Burden of disease in Australia
	Tobacco – 8%
	Alcohol – 3%
	Illicit drugs – 2%

Question 14

Prevalence of disorder

Answer 14

o	USA
	12 mnth – 2%
	Lifetime – 10%
o	AUS
	12 months – 5% (alcojol 3%)
	Lifetime – 25%

Question 15

Demographics of Substance disorders

Answer 15

o	More males
o	Young
	Onset – Mean 19yrs, rare after 25 yrs
o	Single 
o	Low SWS
o	Specific populations
	Aboriginal, Prison, psychiatric

Question 16

Narrated

Prevalence of drug use in Australia (not abuse)

Answer 16

o	Alcohol
•	Biggest burden and highest prevalence despite media coverage of other drugs
	Lifetime – 90%
	12 months – 83%
o	Tobacco
	L – 47%
	12 – 20%
o	Cannabis 
	L – 33%
	12 – 11%
o	The figures on this change but order remains the same
o	Other drugs
	L - < 3%
o	These jump around more varying on decade and availability of various drugs

Question 17

Narrated

Likelihood of substance disorder among different groups

Age of onset

Answer 17

o USA
 Male, native American (indigenous), divorced, Lower SES
 All mean increased risk of disorder

o 15-25

Question 18

Genetic – is there is evidence for genetic contribution?

Answer 18

Yes

o Adoption studies
 4x more likely to abuse alcohol if father has
 Have more alcohol related problems
o Risk for any substance
o Twin studies 40-60% variance
o Onset of alcohol abuse predicted more by shared environment

Question 19

What is inherited?

Answer 19

o Several factors that characterise people who abuse substances – may have heritable components
o Personality – high impulsivity, risk-taking
o High arousal, anxiety
o Increased sensitivity to effects of substance – more active reward pathways
o Decreased sensitivity to negative effects

Question 20

Biochemistry

Answer 20

o Key factor is amount of DA release, particularly in ventral tegmental area (VTA) and hence nucleus accumbens
o Mesolimbic pathway is central in reward learning
o VTA to nucleus Accumbens to PFC
o Mesolimbic pathway utilises DA. DA release from VTA to accumbens increases reward
o GABA also plays a role – inhibitory – release of GABA stops rewarding properties
o Most drugs of abuse increase DA release in ML pathway – either through direct effect on DA or via blockade of GABA
o Also involvement of acetylcholine, NA, glutamate, endogenous opioids, and 5HT

Question 21

Narrated

Alcohol abuse in adopted offspring

Answer 21

o Found an effect for men, not for women
o If no abuse in parents – 12%
o If abuse in m/f – 28%

Question 22

Narrated

Sources of variance in twin similarity for alcohol problems

Answer 22

o	For men suffereing abuse or dependence
	65% genetic
	10% shared environment
o	Women
	10% genetic
	65% shared environment

Question 23

Narrated

Alcohol reduced arousal in response to stressful situation in males with a family history of alcoholism

Answer 23

o Family history
 When sober more reactive to aversive stimulus than controls
 When drunk no reaction
o No family history
 Level of arousal stays the same regardless of alcohol level
o Thus
 Alcohol calms people with a family history of alcoholism more than controls

Question 24

Personality factors

Answer 24

o Two broad factors increase risk
o Anxiousness
 More likely in females
 Comorbidity with anxiety and depression
 Role controversial
• May be causal at onset but later become consequence
o Impulsivity
 More likely in males
 Earlier onset
 Comorbidity with conduct disorder, risk taking

Question 25

Learning factors

Answer 25

o Learning and conditioning process used to explain all aspects of substance abuse (e.g. tolerance, craving) o Two main models  Opponent process theory  Classical conditioning

Question 26

Opponent process theory

Answer 26

o Drug elicits a direct effect – A-state o Body responds with opposite effects to counteract – B-state o A-state is rapid and brief, B-state is slower and longer o B-state grows in speed and intensity with continued use o B-state can condition to external cues

Question 27

Classical Conditioning

Answer 27

o Positive effects and especially compensatory effects of substance can condition to external cues o Thus common cues of drug use (e.g. environment, people, tools) will elicit increasing compensation before effects of substance are experienced

Question 28

Predictions from conditioning theories

Answer 28

o Drug associated cues should elicit craving and withdrawal o If tolerance occurs in one environment, it will occur less in a different environment o Tolerance effect should extinguish o If extinction (treatment) occurs in one environment, craving and relapse are still likely in a different environment

Question 29

Expectancy influences

Answer 29

o Effects of a substance are influenced by the beliefs and expectancies of the effects of the substance o In some cases these can be as or more important that the pharmacological effects o People with substance disorders have stronger positive expectancies of effects o Several common themes – e.g. psychological, social, performance

Question 30

Narrated | Factors in alcohol expectancy Measure

Answer 30

``` o Tension-reduction  Drinking helps me forget my worries o Social lubrication  Makes me less shy o Activity enhancement  More enjoyable o Performance enhancement  Makes me more creative ```

Question 31

Narrated | Reactivity to alcohol-associated stimuli

Answer 31

o Very reactive to fav. Stimuli, led to craving. | o Less reactive but still somewhat to different

Question 32

Narrated | Those with positive expectancies more likely to become a problem drinker. Adolescent study.

Answer 32

-

Question 33

Narrated - loose ends • Rats show environmental attenuation to morphine in pain study • Rats whose tolerance had been extinguished died quicker when given fatal dose of morphine than did rats who hadn’t • Mean amount of drink consumed by alcoholics o Showed that those who thought it was alcohol drank 2.5 more than those told tonic

Answer 33

-

Question 34

Social/cultural aspects

Answer 34

``` o 20% of the world’s population consume 80% of the alcohol o Availability influenced by  Wealth  Proximity  Cultural attitudes  Religious beliefs  Laws ```

Question 35

Family & Parent factors (3)

Answer 35

o Parents may influence onset frequency of substance use through  Availability  Attitudes/expectancies  Behaviours/associations

Question 36

Parenting factors influencing alcohol use in adolescents (5)

Answer 36

``` Evidence for role of:  Availability of alcohol at home  Parental modelling of use  Parent monitoring  Parent-child relationship  General communication ```

Question 37

Narrated | Likelihood of substance use among ethnic groups

Answer 37

o 8-12 times higher if you are indigenous

Question 38

Narrated Halls creek study Reduced opening hours

Answer 38

o When opening hours were reduced o Alcohol consumption reduced o Alcohol-related hospitalisations reduced

Question 39

Narrated | Social alcohol control and use among adolescents

Answer 39

o Higher social controls o Reduces consumption o Both in past month and heavy use o And age of first drink

Question 40

Narrated | Parental attitudes

Answer 40

o Positive attitude leads to parental supervised use and then harmful use in adolescents

Question 41

Narrated Family Factors Rules and availability

Answer 41

o Rules and availability interact in predicting alcohol problems o More available at home predicts problems if you have relaxed rules. o Strict rules with available not a predictor.