Reward System and Substance Abuse Flashcards
Name the four key processes of substance abuse on a psychological level
Negative affect:
(e.g. depression and anxiety): can trigger substance use; on the other hand substance sue can trigger negative affect -> circular downward spiral
Alternative rewards:
Other rewards, such as travel lose importance; reduced sensitivity
Behavioral/cognitve control:
Target of psychotherapy
Habit formation:
Drug use in the beginning is for calming effects etc. later usage is more compulsive
How can the four key processes of substance abuse be conceptualized on a neural level?
The ventral-to-dorsal striatal shift
Increased effects of drug cues and priming are initiated by sensitization processes toward drug cues as well as priming doses in brain regions related to reward processing.
With reward processing chronic drug intake is associated with increased dopamine release and reorganization of the ventral-to-dorsal striatal loops
This again promotes habitual drug intake and impairs behavioral flexibility
Striatum
This region is important to shifts from alternative awards to drug-intake awards
Limbic brain areas
Neuroadaptive processes take place within the limbic and stress hormone system that contribute to negative affect
Frontal Cortex
Impaired cognitive control is attributed to vulnerability factors interacting with neurotoxic and adaptive changes in the PFC
Can alcohol-related disorders be understood as a single category or rather as a continuum
Alcohol-related disorders exist in a continuum, where a certain amount of criteria met (from DSM-V) refers to the severity of the alcohol use disorder
Mental disorders can be primary in developing SUD, as shown here also SUD can be primary in developing mental disorders
Name 5 of the 9 DSM V symptoms of alcohol use disorder
Tolerance
Withdrawal
More use than intended
Unsuccessful efforts to cut down
Spending a lot of time, getting, using or recovering from use
Do mental disorders (MD) cause substance dependence (SUD) or the other way around?
MD can cause SUD and SUD can cause MD
Then there is the possibility, that there is a third, common cause, for both MD and SUD
Name 3 pathogenic factors in substance abuse
Genetics (e.g. gene combinations)
Environment (e.g. sports-teams)
Substance (e.g. substance properties)
How are genetics and alcoholism linked?
see slide:
What percentage of the german population is alcohol dependent? Are there more alcohol or THC-dependent germans?
2 % of germans are alcohol dependent and 2% of the german population is THC-dependent.
What are the 2 main stages of treatment for patients with AUD?
Stage 1:Detoxification
Stage 2: Long term treatment
What are the central structures of the human reward system?
The mesolimbic dopamine system including the Nacc and the VTA.
What type of dopamine release is typical for addiction
All drugs directly or indirectly trigger exaggerated, transient increases in extracellular dopamine in the Nac. High, brief bursts of Dopamine are needed for addiction.
Why are high brief bursts of dopamine so impactful in reducing alternative rewards?
DA surges resemble and surpass the physiological increases triggered by natural reinforcers
Is such fast dopamine increases sufficient for the development of addiction?
No, they are however necessary
What is the positive reinforcement in AUD reinforced by (neurotransmitters)
See slide:
What clinical evidence can be found for persistent changes in the brain, that are related to AUD?
Tolerance
Withdrawal
Persistence of craving over many years
Depression
Decreased response to natural rewards
Possibility of relapse, even many years later
Explain the study conducted on mu-opiate receptor availability, that was discussed in this lecture.
Result: In Patients with AUD craving correlated with opiate receptor availability
Explain the Harry-Frankfurt Freedom of will model in relation to AUD
See slide:
