7: Addiction & Substance Use Flashcards
(42 cards)
Addiction defintion (WHO)?
- repeated used of psychoactive substances
= user periodically, chronically intoxicated - shows compulsion to find and obtain it
DSM Substance used disorder
Need at least 2: - determines intensity .... - intense craving - confused large amount - considerable time to obtain - continued use despite knowing negative consequences - increased tolerance - withdrawal symptoms
What are the major specific substance use disorder?
- Alcohol
- Tobacco
- Cannabis
- Opioid
What is the prevalence of substance used disorder?
16%
- starts early in life
9/10 start before 18
- 9% = multiple substance use disorder
What is the biggest substance used disorder killer?
- tobacco
- 20% of adults globally smoke, predominately men
Which 2 substance contribute/ cause more than 70 other conditions requiring medical care?
- Tobacco
- Alcohol
- drug use
Describe the characteristics of dependent substance users?
- LT use
- Solitary/ small group
- Loss of control
- Usually increasing quantities
What is the process of addiction?
- Tolerance
- Dependence
- shift in homeostasis response
- withdrawal - Compulsion
- Relapse
- high vulnerability
What are Addictive disorder?
There to show that it doesn’t have to be just substances which you are addicted to
- eg gambling
What is the Disease model of addiction?
Island approach: Genetics/ persistent drug-induced changes in brain affect psychological processes = addiction - incurable - only solution = abstinence
What is the medical model of addiction?
- symptoms of drug addiction are physiological + should be treated accordingly (substitutes)
- assumes psychological features of addiction are due to physiological causes
What support is there for the disease model?
Alcohol anonymous
- life long condition
- once you become an alcoholic = either an alcoholic abstaining or not
- no such thing as controlled drinking
According to Alcohol anonymous, how can u start recovery?
12 steps - bases for recovery
- admit helplessness
- trust in program + higher power
How effective is AA (Gossop et al, 2003)?
seems pretty effective
- significant improvements in drinking behaviours, psychological problems + Q of life
- frequent attendance = superior drinkning outcome
What are some problems with AA results?
- seem to only improve drinking problem and not other psychiatric problems that follow up
- often, people who don’t succeed kicked out
What neurotransmitter seems to be at the heart of Neuroscience of addiction?
Dopamine
- Psychoactive substances bind to receptor in brain = changing it
1. Heroin - binds to opioid receptors + triggers dopamine
2. Ecstasy (MDMA) - triggers serotonin + dopamine
3. Cocaine - stimulate dopamine release
- interfers with dopamine removal
What are the different ways drugs can take action?
- Direct agonists
- bind directly to receptors - Indirect agonist
- increase neurotransmitter binding to receptor - Antagonist
- bind to receptor but have no effect on their own
- just block receptors preventing agonist effect
What is the speed of impact?
- Cocaine taken nasally = speedy impact
2. Cocaine smoked = impact in seconds!
What is the dopamine theory of addiction?
- affecting reward system of brain
- makes things pleasurable + memorable
- dopamine being key messengers
- substances = more powerful + reliable than natural reinforcers
What did the removal/ damage of the nucleus accumbens decreased?
Self-administration of heroin in animals
(Willuhn et al, 2010)
What did they find about genetically engineered mice that lacked dopamine receptors? (Palmiter, 2008)?
starve to death
- restoring dopamine signalling in the reward pathway reversed effect
What brain changes can be observed overtime through repeated drug administration?
- enhances brain reactivity to drugs + reduces sensitivity to non-drug rewards
- Amphetamine = structural changes in dendritic spines
- changes lasted more than a month in rates
What are the LT consequences of the brain changes?
Build up of tolerance - neuron is adapting = resetting of reward threshold = increase in maintenance otherwise result in withdrawal - body only functions normally in the presence of drug
What other areas of the brain, other than the reward system, are affected by substance misuse addiction?
Reward system also connected with other brain areas
- PFC - hypoactivity
- loss of inhibitory control
- loss in decision making
