| Term | Definition |
|---|
| what is the prefrontal cortex important for? | modulating numerous aspects of goal directed behaviour |
| how is the dorsolateral prefrontal cortex (prelimbic in rats) involved in goal d. behaviour? | involved in planning/response selection/control of actions; lets animals know that their actions result in outcomes and taht this outcome is the goal |
| what does damage to the prelimbic cortex cause? | reduced ability for animals to detect contingency (based on chance) changes ex: pulling chain/lever press for either sugar pellet or starch. sugar pellet was chance deliver so rats stopped with that action and just did the starch action but with damage they stop both |
| what part of the brain is underactive in someone with depression and controls mood? | anterior cingulate cortex |
| in what area of the brain is info from PFC and amygdala integrated? | nucleus accumbens (reward centre of brain) |
| what is the entire circuit (3 parts) involved with mediating goal-directed behaviour? | PFC--NAC (nuc. accumbens)---amygdala |
| what are the 4 criteria for substance dependence? | tolerance, experiencing withdrawal symptoms, more drug taken than intended, diminished quality of life due to drug taking |
| what are the 3 most common endogenous opiod peptides? | Enkephalin, dynorphin and endorphin |
| where are the receptors for opiods found? | inhibitory GABA neurons in the VTA, stimulation of these receptors inhibit GABA neurons, disinhibit DA neurons |
| what are the different reactions of DA transmitter with cocaine and amphetamine? | Cocaine: blocks the DA transporter, so DA that has been released stays out a lot longer; Amphetamines: Reverses the DA transporter so more DA is released and stays out longer--Also blocks degradation of DA |
| what are the two main theories of drug addiction? | physical dependence model: addicts take drug to not go through withdrawal PROBLEM: addicts relapse even after all withdrawal has passed; Positive reward model: addicts take drugs for the pleasurable feelings PROBLEM: addicts take drugs even if pleasurable feeling has dissapeared |
| conditioned tolerance | tolerance is maximal when its taken in the same place all the time or in the same conditions ex: alcohol given to rats and hypothermia withdrawal symptoms, rats given booze in same place all the time showed no hypothermia |
| conditioned withdrawal | withdrawal elicted by the drug environment or drug associated cues; EX: rats given morphine is same or diff context; withdrawal only observed when animals in same environment |
| explain relationship of dopamine and addiction | dopamine is associated with reward and lesions to this area abolish self administration of drugs (in rats) BUT DA has been found to increase approach behaviours to conditioned stimuli leading to the drug (lever pressing) rather than the actual drug itself (not simply a pleasure molecule); animals will press the lever just for the drugindiced-cue even if they get no reward; prolonged use leads to locomotor sensitization to drug |
| WHAT IS THE incentive-sensitization hypothesis to drug use? | cues associated with drug taking eventually take over behaviour of the addict; tolerance develops to the hedonic effects, however, the effect of the cues associated with drug taking become sensitized; The cues lead to more drug taking even if the effects of the drug are not as pleasurable anymore |
| what system gets activated when cues are shown? | limbic system |
| hypofrontality | reduced function of the orbitofronal cortex in cocaine addicts; could exaccerbate activation caused by cues ex: because of poor decision making skills (loss of frontal cortex) people are implusive--gambling test with advantageous, disadvantageous decks |
Combine with other sets
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