Topic 3: Drug addiction Flashcards
define drugs
chemical substances which interact with the biochemistry of the body.
how do drugs interact with the bodies biochemistry?
inibit or reinforce enzyme activity, block or activate receptirs, interact with NTs and hormones and attack invaders.
what are psycho-active drugs?
chemicals that influence the way we feel or act. interact with the nervous system and the endocrine system.
what are agonists ?
mimics action of the NT
what are antagonists
block action of the NT.
what are the different ways of intake for pharmacokinetics?
digestive tract, respiratory tract, skin, nose, intravenous injection, intramuscular or subcutaneous injection.
pharmacokinetics are distributed what 2 ways?
through water-soluble molecules and lipid-soluble molecules.
what are water-soluble molecules?
directly dissolved in the blood, but do not pass through cell membranes.
what are lipid-solubles molecules?
need carriers to transport them through the blood but can pass directly through cell membranes.
what is the blood-brain barrier?
the brain does not have the capillaries (the gaps that permit the free flow of substances in and out of blood).
What is meant by elimination?
all drugs are eventually eliminated- either chemical breakdown or excretion.
what are the mechanisms that help the body maintain homeostasis?
metabolic tolerance and functional tolerance.
what is the withdrawal affect?
the bodies tolerance mechanism pushing against a door. E.g. if you take a sleepng pill the withdrawal will be insomnia. The tolerance acts against the drugs normal function.
The role of context in the reaction of drugs
is associated, built up this tolerance it is often triggered by the context in which you took it. overdoes easier in novel surroundings, compensatory reactions.
intracranial self-stimulation- Alls and milner found what with the rat
wanted to remote control a rat so that it only stimulates in certain parts of the maze- in theory would avoid this.
what brain areas in the rat require the least amount of stimulation
nucleus accumbens and ventral tegmental areas.
what is the mestoelencephalic dopamine system?
connects mid brain to the end brain and it includes both NA and VTA.
dopamine releases when…
reward is happening and also punishing stimuli as well.
what is the seeking hypothesis?
dopamine has nothing to do with pleasure but the compulsion to do something again and again.
what is psychological dependence?
drugs directly interact with the brains reward system- addicts crave drugs even whilst disliking their effects.
