| I summarized this video by K.C. Berridge about some of his research on dopamine: https://www.youtube.com/watch?v=15TvKADY0QQ * animals that lose their dopamine learning mechanisms can still learn new things * even when dopamine is there, sometimes the system will continue to respond to unconditioned responses that are learned and expected * microinjections of amphetamine do not increase reward expectation - they increase peak of desire for reward - like when food is more tempting after not eating the whole day; sometimes a nasty salty taste is desirable in sodium deficiency, say * system is computing value, rather than learning * incentive-salience is a cue-trigged type of wanting; say someone else across the room lighting up a cig cueing your desire * the cue becomes an attention magnet - the cue is very hard to not want to pay attention to * the mesolimbic state of brain at a certain instant in time plays a huge role in amplifying responses to cues - hunger increases desire for food, repeated experience of drugs amplify the cue for drugs * an addict is a person who will have a super strong dopamine response when provided opportunity, due to sensitization of cue-triggered want - even months after enduring withdrawals, acquired hypersensitivity may still exist |