Psychological Disorders Flashcards
Drugs either facilitate or inhibit transmission at:
Synapses.
What is an antagonist?
A drug that blocks a neurotransmitter.
What is an agonist?
A drug that mimics or increases the effects of a neurotransmitter.
What is a mixed agonist-antagonist?
An agonist of some effects of the neurotransmitter and an antagonist for others, or an agonist at some doses and an antagonist at others.
Explain affinity.
A drug has an affinity for a receptor if it binds to it.
Explain a drug’s efficacy.
Its tendency to activate the receptor.
Who discovered the effects of dopamine and norepinephrine?
Olds and Milner.
What is the nucleus accumbens central for?
Reinforcing experiences of all types.
What do addictive drugs do to the nucleus accumbens?
They release dopamine or norepinephrine.
How do stimulant drugs affect dopamine?
They block reuptake of dopamine or reverse the dopamine transporter so it releases dopamine instead of producing reuptake.
What is the effect of opiates on the brain?
Inhibiting GABA, and increasing dopamine release.
What is GABA?
A neurotransmitter that inhibits the firing of dopamine neurons.
Name some things that release dopamine in the nucleus accumbens.
Sexual excitement, music, sugar, and imagining something pleasant.
Explain craving.
An insistent search for the activity.
Give some genetics predispositions for addiction.
A gene that controls variations in the dopamine 4 receptor. making it less sensitive, and the COMT enzyme that breaks down dopamine after its release.
Name the two types of alcoholism.
Type A/I and Type B/II.
What is type B alcoholism?
Rapid onset, usually before age 25.
What is type A alcoholism?
Developing alcohol problems gradually, usually after age 25.
Alcoholism is more likely among tose who were described in childhood as:
Impulsive, sensation-seeking, risk taking, easily bored, and outgoing.
What is contingency management?
A version of therapy that includes rewards for remaining drug-free.
What toxic substance does the liver convert ethyl alcohol to?
Acetaldehyde.
What converts acetaldehyde to acetic acid?
Acetaldehyde dehydrogenase.
What does disulfiram do?
Antagonises the effects of acetalhyde dehydrogenase by binding to its copper ion.
What do naxolone and naltrexone do?
Block opiate receptor and thereby decrese the pleasure from alcohol.
Give three drugs used to treat heroin addiction.
Methadone, buprenorphine and levomethadyl acetate.
How does propranolol reduce cravings?
Reconsolidation requires protein synthesis, and propranolol interferes with protein synthesis and therefore prevent reconsolidation.
Give some characteristics of major depression.
Feeling sad most of the day for weeks at a time, don’t enjoy anything, lack of energy, feeling worthless, suicidal ideation, insomnia, poor concentration.
The ___ form of the serotonin transporter gene increase the risk of a depressive reaction to major stressors.
Short.
Most people with depression have decreased activity in the ___ prefrontal cortex and increased activity in the ___ prefrontal cortex.
Left, right.
Give some types of antidepressants.
Triyclics, selective serotonin reuptake inhibitors, monoamine oxidase inhibitors, and atypical antidepressants.
How do tricyclic antidepressants work?
They block transporter proteins that reabsorb serotonin, dopamine and norepinephrine into the presynaptic neuron after release.
What do tricyclics block?
Histamine and acetylcholine receptors, and sodium channels.
What are four issues with tricyclic antidepressants?
They produce drowsiness, difficulty urinating, dry mouth, and heart irregularities.
How do monoamine oxidase inhibitors work?
They block the enzyme monoamine oxidase, a presynaptic enzyme that metabolises catecholamines and serotonin into inactive forms.
What do people taking monoamine oxidase inhibitors have to avoid?
Foods containing tyramine (cheese, raisins, etc) as the combination raises blood pressure.
People with depression have lower levels of what neurotransmitter?
Brain-derived neurotrophic factor.
What is brain-derived neurotrophic factor important for?
Synaptic plasticity, learning, and proliferation of new neurons in the hippocampus.
Why do people with depression have a smaller hippocampus, impaired learning, and redued production of hippocampal neurons?
Low BDNF (brain-derived neurotrophic factor).