MH Lecture 5 - Substance-Related Addictive Disorders

Substance-Related Addictive Disorders Diagnostic Criteria

• excessive use of drug

• persistent desire/unsuccessful effort to control usage (distress)

• excessive time devoted to drug seeking behaviours

• strong cravings

• dysfunction in work, school, home, or social life related to drug use

• drug use in hazardous situations (e.g. driving)

• drug use despite aversive outcomes

• tolerance (leading to escalating use)

• withdrawal symptoms

Substances that qualify for SRD

• alcohol

• caffeine

• cannabis

• hallucinogens

• inhalants

• opioids

• sedatives/hypnotics/anxiolytics

• stimulants

• tobacco

• other

+ gambling disorder — operates on the same brain mechanism as substance use disorder

Substance Use Continuum

1. total abstinence

2. rare/social use

3. heavy social use/early problems

4. heavy problem use/early addiction 

5. clear addiction/dependency

Is Addiction a habit 

• stage 1 — voluntary use 

• stage 2 — habitual use 

• stage 3 — compulsive use 

What is a habit

• stimulus-response learning

• inflexible patter of thought/behaviour

• sensitive to triggers/cues

Dark Side of Addiction

• CRF — increased by drug withdrawal symptoms (increases stress response)

• Initial drug seeking is motivated by rewarding aspects of the drug

  • goal = feel happy

• once dependence is formed — drug seeking motivated by stress of withdrawal

  • goal = feel normal

Trouble with treating addiction

• drugs of abuse have wildly different mechanisms 

• impact neuroplasticity in different ways 

• no one size fits all solution 

• only common component is the behavioural pattern of addiction formation 

Treatment Approaches

Exposure therapy

• breaking associations between drug related cues and drug seeking behaviour 

Attentional bias retraining 

• redirecting focus from drug related cues 

Counterconditioning 

• e.g. disulfiram (antabuse) — causes instant hangover 

Other pharmacological approaches 

• e.g. CRF antagonists 

dark side of love

• blocking CRF activity supresses the effects of ‘hearbreak’

• when humans form pair bond — level of CRF in brain skyrockets — particularly in areas to do w anxiety — ready for incoming anxiousness and depression

• the threat of separation is stressful

• drugs and pair bonding interact in a lot of similar ways