10.1 Neurophysiology of Reward and Addiction Flashcards
Motivation is a process that mediates goal-directed responses or goal-seeking behavior to changes in the _______ or _______ _______.
external; internal environment
Reinforcement is the consequence of operant/learned behaviors that ______ ____ ______ that a behavior will be ______ under similar conditions each time.
alters the probability; repeated
Saliency is something important in the _____ ______ worth paying attention to.
surrounding environment
What is a reward?
Objects, stimuli, or activities that have positive value.
Aversion is a ______ reinforcement of behavior that the individual will learn to ____ in future encounters.
negative; avoid
Pleasure is a _____ sensation often referred to as ______ or ______.
positive; eupohore; hedonia
The physiologic purpose of pleasure is to promote behaviors that are consistent with _____ __ ____ and the _____.
survival of self; species
What are natural rewards elicited by?
caring for young, palatable food, mating, and exercise
______ neurons encode the discrepancy between reward predictions and information about the actual reward received and broadcast the signal downstream to reward centers in the brain.
Dopaminergic
An unpredicted reward elicits an activation called a ______ ______ ______.
positive prediction error
A fully predicted reward elicits _____ _____.
no response
Omission of a predicted reward elicits a ______.
depression
Over repeated drug use, the repetition of reward prediction error (RPE) signals would ______ drug-related cues and behaviors.
reinforce
_______ _______ produce error-correcting DA-RPE signals only until the predictions match the actual events.
Natural rewards
_______ is associated with the reinforcing effects of most drugs of abuse.
Dopamine
Drugs of abuse increase _______ _______ concentrations in limbic regions, including the nucleus accumbens.
extracellular dopamine
Drugs of abuse provide _____ and _____ increases in dopamine than natural reinforces such as food and sex.
longer; larger
Which drugs increase dopamine directly?
cocaine, amphetamine, methamphetamine, and ecstasy
Which drugs increase dopamine indirectly via other neuron receptors?
nicotine, alcohol, opiates, and marijuana
Salience refers to a stimuli or environmental changes that are ______ or elicit an ______-______ switch.
arousing; attentional-behavioral
Salience affects the ______ to seek an anticipated reward and facilitates _____ _____.
motivation; conditioned learning
Because dopamine is involved in the _____ of reward and ______, drug-induced increases in dopamine will inherently motivate further procurement of more drug, regardless or whether or not the effects of the drug are perceived as pleasurable.
prediction; salience
Salience leads to a situation in which _____ _____ associated with the drug can increase dopamine themselves and elicit the desire for the drug.
sensory stimuli
What does the mesolimbic system consist of?
nucleus accumbens, ventral tegmental area (VTA), limbic system, and pre-frontal cortex
What are the important neurotransmitters in the mesolimbic system?
dopamine, GABA, opioids, EAAs, dynorphin, and orexin
The main function of the nucleus accumbens is to _____ sensations of pleasure/reward.
suppress
The nucleus accumbens is _______ ______ by a constant trickle of EAAs like glutamate.
constitutively activated
The nucleus accumbens neurons are GABAergic meaning the activation of these neurons stimulate them to _____ _____.
release GABA
GABA is _____, so stimulation of nucleus accumbens neurons will _____ their target.
inhibitory; inhibit
Constitutive inhibition of the pre-frontal cortex targets keeps the brain in a ______-_____ state.
reward-neutral
When you do something that elicits a reward, the _____ becomes activated.
ventral tegmental area (VTA)
Dopaminergic neurons from the VTA project to the _____ _____.
nucleus accumbens
Ultimately, when you do something that elicits a reward, the nucleus accumbens activity (releasing GABA & suppressing sensations of pleasure) is _____.
inhibited
