Motivation & Addiction

PSB 3340 @ UF Dr. Lori Knackstedt L18 Motivation & Addiction

motivation

motivation

purpose for or cause for an action; what causes a person to want to repeat a behavior and vice versa

reinforcement

an increase in the probability that the behavior performed to achieve a goal (reinforcer) will be performed again

secondary reinforces

stimuli around primary enforcer that may acquire reinforcing qualities

Moral Model

Model of drug abuse: blames the abuser for a lack of moral character or a lack of self-control

Disease Model

Model of drug abuse: the abuser requires medical treatment; assumes there is no abnormal condition in the addict’s brain

Physical Dependence Model

Model of drugs abuse: withdrawal avoidance model; abusers use drugs to avoid withdrawal symptoms (negative reinforcement)

Positive Reinforcement Model

Model of drugs abuse: drug use is a behavior controlled by positive reinforcement with no disease

behavior, neurotransmitter

all addictive drugs change ______, therefore they must interact w/ ____________ systems in the brain

increase, reuptake, agonist/antagonist

methods by which drugs interact w/ the brain

• _____ release of a neurotransmitter

• block ______ of a neurotransmitter

  • serve as an _____/______ for a neurotransmitter

nicotine

stimulant that acts as an agonist on nicotonic ACh receptors and is highly addictive

increases heart rate, blood pressure, intestinal activity

cocaine

stimulant that blocks monoamine transporters, especially for DA, slowing reuptake; purified extract from coca shrub

amphetamine & methamphetamine

synthetic stimulants that cause DA release and block reuptake; resemble catecholamine transmitters

biphasic

alcohol’s effects are ______, meaning there is an initial stimulant phase followed by a depressant phase

GABA_A

alcohol ACTIVATES _____{__} receptors → social disinhibition, loss of motor coordination

DA

alcohol STIMULATES ___ pathways → euphoria

fetal alcohol syndrome

damage to the developing fetus after mother abusing alcohol during pregnancy

opiates

drugs that are directly made from poppy seedpods; analgesia (pain killing); HIGHLY addictive

morphine, opium, heroin, codeine

4 examples of opiates

opioids

all drugs, synthetic and nautrally-derived from the poppy, that mimic morphine

oxycodone and fentanyl

2 examples of opioids are

endogenous opioids

peptides produced in the body that bind to opioid receptors

depression, activation, CNS

opioids induce respiratory ________ via (activation/inhibition) of u-opioid receptors in the (CNS/PNS)

Naloxone

u-opioid receptor antagonist that pushes opioids off receptors, saving lives

therapeutic index

separation b/t useful doses of a drug and dangerous doses

drug tolerance

successive exposures to drugs have decreasing effects

metabolic (pharmacokinetic) tolerance

tolerance: organ systems become more effective at eliminating the drug

functional (pharmacodynamic) tolerance

tolerance: target receptor/protein may show altered sensitivity to the drug

down, up

neurons (down/up)-regulate in response to an agonist drug (fewer receptors available) and (down/up)-regulate in response to an antagonist

cross-tolerance

tolerance: tolerance to a whole class of chemically similar drugs

sensitization

drug effects become stronger w/ repeated treatment

(EX: cocaine sensitization → more anxiety)

increased, nucleus accumbens

microdialysis studies show that DA levels are ______ in the _____ ________ following administration of every addictive drug

learning, behavior, attention

DA release promotes _____, _____ strategies, and _____

over-learning

excessive DA release causes “____-_______” of drug-seeking behaviors

medial/anterior cingulate

the “GO” circuit is found in the _____/______ ________ cortex and is involved in regulating and engaging in motivational tasks and attention

orbital

the “STOP” circuit is found in the _______ cortex and is involved in providing inhibitory control over behavior

Disulfiram

treatment for addiction: prevents metabolism of alcohol and leads to build-up of acetaldehyde, which makes people feel sick

naltrexone

treatment for alcohol addiction: opioid receptor antagonist

acamprosate

treatment for addiction: glutamate and GABA

Chantix

treatment for nicotine addiction: nACh receptor partial agonist

replacement therapies

treatment for opioid addiction: methadone, buprenoprhrine, suboxone; intended to replace opioid use

cocaine and methamphetamine

there are no FDA-approved drugs for ______ and _________ addiction