Neuro
Mesolimbic pathway is known as the
final common pathway for reward pleasure and please seeking
Drugs of addiction have different structures and NTs targets in the brain but they all exhibit?
Acute reward- extreme euphoria
chronic reward- euphoria, but not excited
sensitization- of receptors with drug use
negative withdrawal symptoms
associative cue learning- ppl, places, and things)
incentive motivation-relapse
(impulsivity ------>compulsivity = Addiction to Abuse)
Stages of addiction?
May start as voluntary but for addicts no loner a choice
pleasure received from various stages of the brain's natural reward system promotes continued use
repeated exposure to drugs induces the brain's mechanism (need drug to avoid withdrawal=dependence)
dependence leads to daily use to avoid unpleasant sxm of withdrawal
prolonged use leads to brain changes (may be irreversible) that may underlie compulsive drug seeking behavior and consequences which is addiction
Role of PFC
regulates judgement planning and executive fxn
send inhibitory signals to the VTA DA neurons in the mesolimbic reward pathway overcome impulse of instant gratification
Addiction is about _________ & __________
behaviors & consequences
It starts at the VTA and ends up at the?
Nucleus Accumbens
All drugs mimic the brains NTs examples?
other drugs can stimulant, block, and reuptake. to be a drug of abuse it has to mimic NTs
ETOH-Gaba
Cannabis- cannabinoids
Opiates- mu opiate
Nicotine- Acetylcholine
Hallucinogens- 5HT
ETOH/PCP- glutamate
Dependence is _____ in DSM
Ecstasy ______ away receptors, classified as a _________ but is ___________ drug hitting multiple areas of the brain
not
burns, hallucinogen, behavioral
in the Cognitive change model, stimulant drug users damage the ___________ ________ that carries the inhibitory signals from the PFC to the MLRPW
Chronic ETOH uses have ______ GABA which is used to signal the MLRPW to release _________
Opiates damage the _______ ___ _____ itself
frontalstriatal loop
Low, DA
PFC
Essential Features of SUD
cluster of behavioral, cognitive, and physiological symptoms indicating an individual continues use despite significant substance related problems
change in brain circuits may persist beyond detoxification with pts with severe disorders
The mesolimbic pathway depolarizes and releases_______ and we feel contentment
Dopamine
Which drugs bypasses the VTA and goes straight to the Nucleus Accumbens?
What is the most addicting drug?
Cocaine, Amphetamines. psychostimulants
work in reverse of SSRIs. they cause reuptake mechanism to spin in the opposite direction which causes an increase release of DA. causing a rapid flooding of DA.
that's why crack is snorted goes directly in the blood stream and bypasses the blood brain barrier.
Cocaine
What are the biological models of addiction?
Change Set point Model -
Cognitive Deficits Model
Stress can ________ drug levels in addicts
Rationale:
trigger
abuse drugs raises the level of cortisol which plays a primary role in stress response
cortisol raises the level of active in the MLRW system
attributes to the abuser to take drugs in the 1st place and continued usage
SUD Criteria
4 patterns of behaviors
Risky use-physically hazardous
Impaired control- larger amts over longer period of time
Pharmaogical criteria- tolerance withdrawal
Social impairment-unable to fulfil work/home duties
Dopamine is ________ 1st then experience __________
released
pleasure
When nicotine hits the __________ receptors _______ it
When other drugs of abuse hit the receptors they _________ it
chain smokers acetylcholine continues too?
Acetylcholine , desensitizes
stimulate ( wears off in 2-4 hours)
stimulate
Explain Change set Model
not sure if current page 5
drug alters biological or psychological settings or baseline. Variant #1 drugs tell brain to stop making/storing/releasing DA in the VTA after pleasurable activities=no happiness d/t decreases 5HT and INREASED NE in th locus Corelus= withdrawal
Variant #2 DA becomes dysfunctional INCREASING glutamate. continued drug use = increase autoreceptors shutdown DA leaving it depleted leads to withdrawal
Variant #3 sensitivity to environmental cues. during times when drug is not available brain remembers the drug =cravings ( increased glutamate and NE)
NTs act alone
Tolerance:
Withdrawal:
Person need more an more of the drug to get the same euphoria
predictable cluster of s/s following an abrupt discontinuation or rapid decrease in intake a a drug that has been used continuously over a period of time
substances in a similar pharmacological class produce similar withdrawal sxm
withdrawal also depends on the point of entry
________ ___ _________is the process of which a substance on which an individual is physically dependent is gradually eliminated from body
Goals of this process (3)
Management of withdrawal
safe, humane, and prepare for ongoing tx (need therapist to start the process
(federal government)
All drugs of abuse end up at the VTA except ?
whenever a drug of abuse is used in the beginning DA is produced how many times then nahual concentration?
Cocaine
10-100 Xs
Drugs were discovered ________ NTs
They look at the _________ manifestation of drugs
before
behavioral
Types of cravings?
Cue based- response to environmental stimuli most notable with cocaine & nicotine(external give Buprenorphine)
State or stress based: arises out of stress emotional tone (ETOH & Sedatives d/t anxiety)give Acamprosate
Opiates have both Cue and state cravings
Behavioral Criteria for Substance Use Disorder
A problematic pattern of substance use leading to clinically significant impairment or distress as manifested 2 out of 11 criteria manifested occurring in the same 12 month period
Severity of addition depends on how many criteria are met
Withdrawal initial assessment includes
evaluation of predicted withdrawal severity
medical comorbidity
psychiatric comorbidity