Drug Addiction Flashcards
1
Q
DSM- 5 substance- related + addictive disorders
A
- Alcohol, caffeine, tobacco , cannabis
- Alcohol related disorders- criteria A:
- problematic pattern of alcohol leading to clinically significant impairment / distress - 2 of the following occur within 12 months
- persistent desire / unsuccessful effects to cut down
- lots time spent obtaining alcohol/ recover
- recurrent alcohol use
- Tolerance
- withdrawal
2
Q
Neuropsychology - Mesolimbic Dopamine system
A
- ventral tegmental area projects to nucleus accumbens via mesocortical dopamine projection
- VTA projects to medial prefrontal cortex via mesoaccumbens dopamine projection
3
Q
Electrical Brain stimulation
A
- Mispositioned electrode probe in region that passes the medial forebrain bundle ( mfb)
- Mfb is major highway from neural tracts including mesoaccumbens dopamine projection
- Rats induce electrical current in Mfb region themselves (intracranial self- stimulation)
- Olds found rats constantly pressed button for brain stimulation ( activates mesolimbic dopamine system)
4
Q
Electrical brain stimulation in humans - Bishop et al
A
- intracranial self-stimulation reinforced in humans
- show tray of food to hungry people
- Didn’t want to stop brain stimuIation even for food - addicted
5
Q
Mesoaccumbens dopamine + reward
A
- Dopaminergic activation in striatum correlates with self- reported high
- cocaine activates nucleus accumbens (releases dopamine)
6
Q
chronic Drug use - striatal impact
A
- Daley et al
- PET scans shows reduced dopamine receptors in cocaine addicts
7
Q
smoking + accumbens dopamine function
A
- Weirs et al
- smoking reduces number of D 2 dopamine receptors + dopamine release
8
Q
cocaine + grey matter volume
A
- Franklin et al
- reduced frontal grey matter volume in cocaine addicts
9
Q
conditioning + dopamine - Pavlov
A
- mesoaccumbens dopamine projection modulates efficacy of conditioned stimulus
- dopaminergic activation in nucleus accumbens following repeated presentation of reward cues
- reward cues ( conditioned stimulus) can produce a large activation nucleus accumbens + dopamine release
10
Q
conditioned drug effects
A
- Robinson , Berridge + Alderige
- drugs are addictive because activate mesoaccumbens dopamine projection = drug - associated stimuli to acquire conditioned properties
- re-exposure to drug- associated stimuli at a later date activates memories of drug = craving
11
Q
pharmacological treatments
A
- Nicotine : patches/gum - maKes withdrawal + craving more manageable (don’t get hit when you have a cig)
- Opiates: methadone - mild, non-high inducing version of heroin - prevents withdrawal + craving
- Alcohol: Antabuse- inactive till alcohol consumed then causes nausea + dizziness
12
Q
Extinction Therapy
A
- repeat presentation of Pavlovian conditioned stimuil elimilate conditioned response ( dopamine release)
13
Q
Psychological treatment
A
- Heroin addicts cue exposure followed by extinction therapy eased craving response
14
Q
Effects Marijuana
A
- relaxed + sociable
- large dose = rapid shift in emotion, impaired memory
- Extremely heavy dose = hallucinations
- can interfere with cog functioning
15
Q
Physical consequences of Marijuana
A
- short term= bloodshot + itchy eyes, dry mouth , increased appetite+ raised blood pressure
- long term can impair lungs
- regular user fMRI scans show different patterns of connectivity between amygdala + cortex when reg neg emotions
- Tolerance + withdrawal symptoms = restlessness , depression + anxiety
