Motivation Control System Flashcards
What are the challenges of studying addiction in human populations
history of past drug exposure is hard to know
ethical barriers
what are the challenges of studying addiction in animal models
do not recapitulate all aspects of SUD
endophenotypes of addiction must be studied
what is tolerance
REDUCED brain response following repeated drug exposure
what is sensitization
ENHANCED brain response following repeated drug exposure
what is dependence
altered brain function upon cessation of drug use
often opposite of drug effect
what is incentive theory
our behavior is directed by a desire for external rewards
what is hedonic impact
the pleasure we experience from an action
what is incentive salience
our actual motivation to obtain something we like
What is incentive sensitization theory
Model to explain drug craving as a manifestation of incentive salience which becomes stronger with repeated drug use
Wanting and Liking Theory
Pleasure (liking) associated with early drug use
Craving (wanting) associated with chronic drug use
what is hedonic homeostatic dysregulation
mood undergoes allostatic changes with repeated drug exposure; key brain structures undergo neuroadaption as the individual cycles through Preoccupation Anticipation, Binge Intoxication, and Withdrawal Negative Affect
what is the reward circuit of the brain
VTA, NAc, Amygdala, ventral pallidum, hippocampus, prefrontal cortex
VTA under GABAergic inhibition
what is the mesolimbic pathway
dopamine neurons send their axons from the VTA to the NAc
what is the learning and memory system of the motivation control system
hippocampus
amygdala
what is the motor output part of the motivation control system
cortex
what is the motor loop of the motivation control system
thalamus
basal ganglia
what is the reinforcement system of the motivation control system
nucleus accumbens
ventral tegmental area
What are the five brain areas involve in reinforcement and reward
VTA
nucleus accumbens
basal ganglia
hippocampus
prefrontal cortex
Describe the reinforcement system
VTA releases dopamine onto NAc
NAc releases neuropeptide onto VTA
What is the VTA
source of dopamine cell bodies sending axon projections to the nucleus accumbens
what is the nucleus accumbens
receives dopamine inputs from the VTA
all addictive drugs produce an increase of dopamine here
what is the basal ganglia
increases motor output to produce an overall increase in behavior
what is the hippocampus/amygdala
tells the nucleus accumbens where we are and what is happening around us
gives environment stimuli “incentive salience”
what is the prefrontal cortex
provides the nucleus accumbens with several option for behavior
What does DA do to the NAc
DA turns of NAc inhibition of the basal ganglia
