Neurobiology of Addiction Flashcards
What is the criteria for dependance?
Strong desire to take substance Difficulties in controlling substance use Physiological withdrawal state Tolerance Neglect of alternative pleasures Persistence despite evidence of harm
What does CAGE stand for?
Cut-down
Annoyed
Guilty
Eye-opener
Where does blood flow increase to when a non-addicted gambler wins?
Striatum
What is the cause of tolerance to reward?
Due to repeated dopamine release, dopamine receptors down regulate
What part of the brain has increased activity when an addict is presented with their cues?
Orbito-frontal cortex
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 matures later, the frontal lobe or the limbic (emotional) symptoms?
The frontal lobe that mediates executive functioning
How does the frontal lobe mature?
Back to front
Begins in the primary motor cortex and spreads anteriorly over the superior and inferior frontal gyri, with the prefrontal cortex developing last
What are the effects of dopamine release?
Ability to update info in the PFC
Ability to set new goals
Ability to avoid compulsive repetition of a behaviour
What do addictive drugs do regarding dopamine?
Provide a signal that disrupts normal dopamine related learning in the PFC
What parts of the brain are involved in drugs stimulus learning?
Hippocampal
Striatum
Amygdala
What are the hippocampal, striatum and amygdala parts of the brain critical for with regards to drug stimulus learning?
Acquisition
Consolidation
Expression of drug stimulus learning
What is the striatum directly involved in?
Habit learning
What is the hippocampus directly involved in?
Declarative learning
What does acute stress cause the release of?
Dopamine
