Neurobiology of addiction Flashcards
What is the role of the pre frontal cortex?
- Helps intention guide behaviour
- Modulates the powerful effects of the reward pathway
- Sets goals, focuses attention
- Makes sound decisions
- Keeps emotions and impulses under control to achieve long term goals
What is the ICD-10 criteria of dependance?
- A strong desire to take the substance
- Difficulties in controlling substance use
- A physiological withdrawal state
- Tolerance due to increased use of substance
- Neglect of alternative pleasures
- Persistence despite evidence of harm
What is regarded as “gaming disorder” by ICD-11 and what is it’s characteristics?
a pattern of gaming behavior (“digital-gaming” or “video-gaming”).
Characterised by:
- impaired control over gaming,
- increasing priority given to gaming over other activities to the extent that gaming takes precedence over other interests and daily activities,
- continuation or escalation of gaming despite the occurrence of negative consequences.
Criteria for gaming disorder to be diagnosed?
For gaming disorder to be diagnosed, the behaviour pattern must be of sufficient severity to result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning and would normally have been evident for at least 12 months.
Cortical maturation progresses in a front to back direction. true/false?
False
Cortical maturation progresses in a back-to-front direction, beginning in the primary motor cortex and spreading anteriorly over the superior and inferior frontal gyri, with the prefrontal cortex developing last
Frontal lobe areas that mediate executive functioning mature later than limbic (emotional) systems. true/false?
True
What are the effects of dopamine release?
Ability to update information within the PFC (prefrontal cortex)
Ability to select new goals
The ability to avoid compulsive repetition of a behaviour
How do addictive drugs disrupt the normal effects of dopamine release?
Addictive drugs provide a potent signal that disrupts normal dopamine-related learning in the PFC (pre-frontal cortex).
What other areas of the brain are involved in the maintenance of addiction?
Hippocampus and amygdala
What are the amygdala and hippocampus critical for?
The hippocampal and amygdala are critical in acquisition, consolidation and expression of drug stimulus learning.
What are the features of the orbito-frontal cortex?
Provides internal representations of the saliency of events and assigns values to them
Key creator of motivation to act
Addicts show increased activation of OFC when presented with drug cues
Hyperactivity correlates with self reported drug cravings following exposure to cues
Overall changes in OFC persist into abstinence
How stress influences dopamine release?
Acute stress triggers release of dopamine in the neural reward pathway.
Chronic stress leads to dampening of dopaminerigc activity through down regulation of D receptors.
This reduces sensitivity to normal rewards
Encourages exposure to highly rewarding behaviours
Rapid increase in stress can motivate drug seeking in dependent individuals.