Effect of recreational drugs Flashcards
what is a drug?
a chemical that has an effect on humans
what is a recreational drug?
a drug which is taken for pleasure
how do drugs (medical and recreational) affect the biology of the brain?
by altering the availability of one or more neurotransmitters
what do stimulant drugs do?
speed up messages travelling between the brain and body
what are the effects of stimulant drugs?
they can make a person feel more awake, alert, confident and energetic
what is the effect of depressant drugs in small doses in people?
a person can feel more relaxed and less inhibited
what is the effect of depressant drugs in large doses in people?
they can cause vomiting, drowsiness, unconsciousness and even death
what do depressant drugs do?
slow down the messages between the brain and body
what are the effects of depressant drugs?
they effect concentration and coordination, slowing down reaction time and reduce arousal and stimulation
how do recreational drugs produce effects?
by changing the function of neurotransmitters either by increasing/decreasing the level of a particular neurotransmitter / changing level of uptake
what encourages people to take recreational drugs?
they can produce a pleasant sensation as the reward pathway in the brain is stimulated which encourages individuals to repeat the behaviour
what happens to the production of neurotransmitters when someone takes a depressant drug?
the brain increases its production of the neurotransmitter to compensate and so the person needs to continue to take the depressant
what neurotransmitter has the central role in the effect of all recreational drugs
dopamine
how does cocaine block the reuptake of dopamine?
by binfing with dopamine transporter molecules of the terminal buttons of the presynaptic neuron
what are the long-term effects on dopamine of cocaine?
dopamine receptors become down regulated. Fewer receptors are active, some shut down and the number of dopamine produced declines.
what affect does heroin have on dopamine?
increases amount of dopamine in reward pathway and boosts activation of dopaminergic synapses which causes a feeling of euphoria
what depressant effects does heroin have on the CNS?
slows down activity of neurons involved in pain and CNS
what is heroin processed into once at the brain?
morphine
how does the brain react to the sudden increase of dopamine?
reduces its own natural production
what happens when the heroin effect on the dopamine system wears off?
the person has less dopamine than they would have for normal brain functioning
what effect does dysphoria have after heroin wears off?
it motivates the person to take more to stop feeling bad and reproduce the high
how is heroin an agonist?
mimics the action of another natural biochemical
What are the long-term effects of heroin use?
the opioid receptors on postsynaptic neurons are constantly binding with morphine molecules which desensitises them to the effects of the drug.
what are some addiction risks of heroin?
-sharing needles is very risky as theres the possibility of catching/spreading a virus
-damage of veins and arteries; can develop a blood clot or lead to gangrene (loss of limbs)
-heroin sedates you and prevents you from coughing therefore if you vomit you wont be able to clear your throat and can block you from breathing- LEAD TO DEATH
- what are heroin users given?
- what is it?
- Methadone
- a synthetic opioid which is “safer” than street heroine
what are some credibility points of drugs? (Coda)
- Stralker and Mackie (2005) found that cannabis had an effect on the hippocampus of mice
- observations of humans have shown that those who take drugs initially experience pleasure and then often become addicted (face validity)
-Old and Milner (1954) found a pleasure centre in the brain
How is the theory of drugs reductionist? (cOda)
The brain is complex an there is more than one reward pathway in the reward system and more than one grin region involved, so having one explanation for the mode of action of a recreational drug is too simplistic.
how is the generalisability of drugs risky? (cOda)
mainly non-human studies have been used to understand drug effects on human CNS transmission. The basic transmission is similar however some differences arise because the human brain is more complex than the rat brain
doesn’t take situational factors into account such as peer pressure, social situation, cognitive issues and learned behaviours.
