Recreational Drugs Flashcards
neurotransmitters
chem messengers that act between neurones in brain and can be excitatory or inhibitory
dopamine
emo and cog func > reinforcement in learning and addiction E
acetylcholine
muscle contraction, motor func, cog func- attention,memory,learning E
serotonin
mood control in lymbic system > feelings hunger and pain
inhibitory
norepinephrine
emo, mood control and sleep E
reward pathway
located limbic system
1) stimulus recog > VTA stimulated= prod dop and travels to NAc
2) NAc dop binds receptors > affect activity = pleasure feelings
3) prefreontal c connectspleasure from NAc to orig trigger stimulus> enc repeat behaviour that stim VTA
4) rp is evolved eg adaptive when high calories food= fat for famine
5) drugs hijack rs= prod pleasure without adap func
glutamate
continuing path of messages w active ast func in memory, cog, mood reg E
recreational drugs
psyhoactive subs alters brain func eg mood, perception, consious exp
inc or dec neuro lev in synaptic cleft
cocaine mode of action
binds to uptake pump> block dop reuptake= inc dop activity
synapse= surplus dopamine> euphoria
cocaine effects
receptors downregulated= few receptors active= dop declines
withdrawl> craving for high dose to exp same effect
PCP action
recued neuronal activity= anaesthetic effect less pain + inhibition of excitatory in brain eg hippo, cerrebelum= memory loss
dec dopamine pathways= hallucinations
PCP effects
tolerance for PCP as nmda receptors downreg= red func nmda glutamate recep= high dose
without= physical symp eg pain, mental health change
herion action
triggers endorphins= hyperpolarise post syn
red neuronal act= stops pain sig procesing
heroin effects
opiod rec downreg= endorphins decline
pain= crave more= high doses to exp same feeling
strength
I olds and milner 1954 pleasure centre rat brain
J press leavers= current , brain stimulation at nucleus accumben= 2000/hr
E dop main to aid neural signaling= reward pathway
HOWEVER= human brains arent same> diff to generalise rp finding from rat to humans
weakness
I isolating single neuro oversimplifies addiction due to indv diff
J no exp> regular dose= overdose >brain expects High lev of chem in some situation >rush
E overcome > develop craving when returned to place
However paired w cog therapy involves choices so works best
Addiction
Withdrawal= brain doesn’t operate normally as it adapts to changes by. Drug
Tolerance= high dose for same effect> brain adapts and stops own prod
Low dop= drug for high dop
