session 14 Flashcards
Physiology of Addiction
The nucleus accumbent responds strongly to reinforcing stimuli. A midbrain structure gives rise to dopamine pathways
- causes “wanting” more than “liking”
Tolerance
needing more of the drug to achieve a high
Withdrawal
causes a physical feeling of discomfort when the drug is absent from the system
Genes for Addiction
genes that correlate with alcoholism, genes that…
-predispose them to higher levels of stress and anxiety
-produce less dopamine
-lead to poor risk management
Genes for prevention
genes that make metabolizing alcohol difficult
-become hungover almost immediately, rarely abuse alcohol
“Antabuse”
pill that immediately causes symptoms of being hungover
-can be used to curb alcoholism
-only as effective as willpower, must be taken routinely
-placebo just as effective
Methadone
a drug that helps with opioid addiction
-“time-release” heroin
-provides a low-level drug to prevent withdrawal
-no risk of overdose
-helps physical dependence, not psychological dependence
clinical depression
lack of happiness than an increase in sadness, feelings of lethargy, worthlessness, helplessness
Physiology of depression
-some evidence of different versions of serotonin transporters and how they mediate response to stressful events
-no evidence of specific genes that consistently cause the disorder
Tricyclic Antidepressants
first anti-depressants blocks the reuptake of serotonin, dopamine, and norepinephrine into the presynaptic neuron
-many side effects
-block some acetylcholine and histamine
Monoamine Oxidase Inhibitors (MAO-Is)
breaks down and inactivates the catecholamine family of neurotransmitters
-DANGEROUS, last resort
-patients have to avoid foods containing tyramine
- leads to unsafe rises in blood pressure
Selective Serotonin Reuptake Inhibitors (SSRI’s)
-most common anti-depressants
-focuses only on the reuptake of serotonin at certain receptor sites
-generally safer, fewer effects
neurotrophins
released early in the nervous system development in response to activity-allow synaptic strengthening and survival
Brain-derived neurotrophic factor (BDNF)
increased activity from all of the extra neurotransmitters present following anti-depressant use also triggers the release of a lot of BDNF
-leads to new neuronal growth in the hippocampus, which can facilitate new learning
Schizophrenia
0.5%-1% worldwide, more common in cities, and more common in males
-“schism” between patient and others
-deterioration of function for at least six months
-positive symptoms (hallucinations, delusions, disorganized speech)
-negative symptoms (social withdrawal, lack of appropriate emotional affect)
