Functional Neuroanatomy of Addiction (6.2) Flashcards
What is the central feature of addiction?
Compulsive drug use despite adverse consequences
What does addiction pathophysiology involve?
The brain reward system and the alterations that reward enhancing drugs effect on this system
Where are dopamine cell bodies located?
Ventral Tegmetal Area (VTA)
Where does the VTA project to?
Nucleus accumbens (NA) and Prefrontal Cortex (PFC)
What is the “reward center” of the brain?
Nucleus accumbens (NA)
How does the NA function?
Integrates VTA (dopamine) and PFT (glutamate) inputs to determine motivational outout
What is the function of the Prefrontal Cortex?
exerts executive control over midbrain structures, cost/ benefit analysis and judgement
What are the sections of the PFC that are involved in addiction/ reward behavior?
Dorsolateral PFC
Ventral medial PFC
OFC
ACC
What does the DLPFC do?
statistical analysus, prioritizing, top down control center
What does teh MPFC do?
assigns emotional valience
What doe OFC do?
impulse prevention
What does ACC do?
vigilance
What changes in the brain does chronic drug use lead to?
Reward circuitry changes that promotes further drug use by:
1- increasing limbic function
2- decreasing PFC function
Explain the limbic drive?
1- VTA supplies DA to the NA
2- NA receives the input and chooses how to respond
3- Amygdala assigns a pleasure threat, or an emotional value to the linkage between 1 and 2
Explain cortical control?
1- OFC should suppress dangerous or addictive things
2- VMPFC should attache positive feelings to not do dangerous things
3- DLPFC should calculate the true risk/ benefit ration of doing addictive things
(the “wranglers” that try to control NA and VTA)
