Chapter 4: Epidemiology and Neurobiology of Addiction Flashcards
Things considered for the criteria for substance schedule placement under the Controlled Substances Act (CSA)?
- Currently accepted medical use in treatment in the United States?
2.Relative abuse potential?
-drugs that can serve as a reinforcer in operant conditioning
- Likelihood of causing dependence when abused?
Describe Schedule I drugs?
-No currently accepted medical use in the United States
-A lack of accepted safety for use under medical supervision
-A high potential for abuse.
Examples include: heroin, LSD, marijuana, peyote, and ecstasy, “spice”, and “bath salts.
Describe Schedule II drugs?
Substances have a high potential for abuse, which may lead to severe psychological or physical dependence.
-support self administration but ALSO have medical utility
Examples of opiates include: methadone (Dolophine®), oxycodone (OxyContin®, Percocet®), fentanyl (Sublimaze®, Duragesic®), morphine, opium, and codeine.
Examples of stimulants include: amphetamine (Dexedrine®, Adderall®), methamphetamine (Desoxyn®), and methylphenidate (Ritalin®).
Describe Schedule III drugs?
Substances have less potential for abuse than substances in Schedules I or II and abuse may lead to moderate or low physical dependence or high psychological dependence.
Examples include: products containing not more than 90 milligrams of codeine per dosage unit (Tylenol with Codeine®), buprenorphine (Suboxone®), ketamine, and anabolic steroids such as Depo®-Testosterone.
*pointed out most in this course: anabolic steriods
describe Schedule IV drugs?
Substances have a low potential for abuse relative to substances in Schedule III.
Examples include: alprazolam (Xanax®), clonazepam (Klonopin®), diazepam (Valium®), lorazepam (Ativan®), midazolam (Versed®), and triazolam (Halcion®).
despite opiods being widely abused, because they are not shown in labs
describe Schedule V drugs?
Substances have a low potential for abuse relative to substances listed in Schedule IV and consist primarily of preparations containing limited quantities of certain opiates.
-edging up to what you can buy over the counter
Examples include: cough preparations containing not more than 200 milligrams of codeine per 100 milliliters or per 100 grams (Robitussin AC®, Phenergan with Codeine®).
what is the National Survey on Drug Use and Health (NSDUH) ?
Annual SAMHSA survey of substance use, misuse, or addiction in U.S. individual age 12 years and older
The questions ask whether the respondents used the respective substances at any time in their lives, at any point in the last year, or during the last month (also termed as current use ).
results from the National Survey on Drug Use and Health (NSDUH) ?
27 million current illicit drug users
6.5 million nonmedical users of psychotherapeutic drugs, including 4.3 million nonmedical users of pain relievers
One in five young adults (18 to 25 years) current users of illicit drugs
what is the Monitoring the Future study (2015) and what were the results?
Surveys drug use, behaviors, attitudes, and values of U.S. secondary school and college students and young adults
Modest increase from 30 to 38 percent in cannabis use; daily use decline from 5.0 to 4.6 percent
No significant increase across broad spectrum of drugs
Continued decline in cigarette and alcohol use
Annual prevalence decline for synthetic marijuana, heroin, MDMA, sedatives, and nonmedical prescription drug use
can see declines and increases in drugs reflecting societal attitudes
what did this revolutionary article by wise “A psychomotor stimulant theory of addiction” state about addiction?
withdrawal, dependence and tolerance are not useful concepts in understanding why people become addicted drugs
it is about their capacity to serve as rewards
how is the Mesolimbic dopamine pathway associated in addiction?
- Critical link in brain’s reward circuitry
-The dopamine pathway from the VTA to the NAc is critical to addiction - Drugs of abuse enhance dopaminergic action
-most abused drugs increase the amount of dopamine that is released from the VTA onto the NAc, amygdala, hippocampus, and frontal lobe.
Olds and Milner found what in the 1950s?
Existence of reward circuit in rat brain through electrical stimulation of brain
what is the Brain Disease Model of Addiction (BDMA)?
suggests that Drugs of abuse act through same reward system and it’s their capacity to serve as rewards that promotes repeated use
The exposure to these drugs promotes neurobiological changes that are responsible for cravings and relapses
-they change the brain that further reinforces uses in a feedback circle
Most abused drugs share common action with
mesolimbic dopamine pathway
which structures is the mesolimbic dopamine pathway connected to?
Hippocampus
Amygdala
Prefrontal cortex
what does the mesolimbic dopamine pathway function as… what does it do?
a feed forward system
it orients towards stimuli and motivates to consume and interact with these things
things like sugar, salt, fat, sexual stimuli
pavlovian: UCS
skinner: primary reinforcers
explain this graph
shows the reward circuit with the major structures involved in the subjective sensation of pleasure and reward.
-these brain regions are responsible for directing us to stimuli
-The pathway starts with dopamine-releasing neurons in the ventral tegmental area (VTA).
-Axons from the VTA neurons release dopamine onto the amygdala, nucleus accumbens (ventral striatum), and prefrontal cortex.
Two Theoretical Perspectives on Addiction?
- The “Exposure Orientation”
-suggests that drugs cause the addiction and is therefore a pharmacological phenomenon
strong position: addiction is inevitable given sufficient exposure to drug
compromised position: drug exposure is necessary for addiction, these individuals are vulnerable to addiction (it is genetic)
-seperates drug addiction from other “addictions” - The “Adaptive Orientation”
-drug pharmacology is not that important to explain drug addiction
-Drug and Non-Drug Addictions Homologous (different manifestations of the same underlying biology)
-extreme relationship that humans develop with ‘things’
-qualities of the individual determines the risk of addiction
-best Understood like other forms of Psychopathology such as Depression
what is the psychomotor Stimulant Theory of Addiction?
An “Exposure Theory”
-attempts to isolate those drug actions that are responsible for habitual, compulsive, non-medical drug self-administration
what does wise & bozarth suggest about the “exposure theory”?
*“Attempts at a general theory of addiction are attempts to isolate – from a variety of irrelevant actions – those drug actions that are responsible for habitual, compulsive, non-medical drug self-administration”
-it is the pharmacological properties of the drug that are responsible for habitual drug use
*-“Crux of the theory is that the reinforcing effects of drugs can be predicted from their ability to induce psychomotor activation
-reinforced to move towards the drug again, due to the psychomotor activation
-“. . .The theory implies that the strength of the psychomotor stimulant properties of a drug should predict the strength of the reinforcing action of that drug. . .If stimulant and unwanted side effects of ethanol, benzodiazepines, and cannabinoids could be separated, drugs of these classes might be found to be more addictive. . .”
one of the problems of the exposure theory?
that rats cannot self-administer the drugs as humans can
describe the idea of homology vs. analogy?
drugs that people abuse are homologous- they work an similar biological mechanism
other kinds of addiction, although they look that way from the outside, do not work this way
in terms of drug use, what does homology mean?
specifically in regards to the evolutionary theory?
the assumption that knowledge of one of these phenomena may provide insight into others
example: finding out how cocaine addiction produces reward can provide insight into alcohol addiction (they share a homology)
what is homology and how is it related to biological evolution?
Different Organs or Behaviors can derive from Common Ancestral Origins and Common Biological Mechanisms.
Therefore, having knowledge of one homologous organ basically has some value in the study of other mammals, even if they appear different on the surface
Key concepts associated with the Evolutionary Theory”
- the four limbs of humans can help us know more about the limbs of cats or dogs
example of one of the Core Concepts in Categorization?
homology
Attempts to Find a common Denominator for a Number of Behaviors are made in the hope that…
they will yield Knowledge that Generalizes from one Case to the Others
are Varied Instances of Drug Dependence homologous?
no, and they have very little heuristic value to eachother
why are the Seemingly different Phenomenon of Addiction, Positive Reinforcement, and Psychomotor Activation Homologous.?
Result from activation of a common Brain Mechanism
This Homology forms the basis of the Psychomotor Stimulant Theory of Addiction
what does Analogy mean?
Surface Similarity between Organs or Behaviors but it does not extend beyond these
Prediction of Something from one side of a Analogy to another likely reflects Similar Environmental Pressures not a Common Ancestral Origin
Classic Example: : Invertebrate (Octopus) versus Vertebrate Eyes
-both organs transduce light and visual stimuli, but do not share common biological mechanism from the evolutionary past
is the relationship between drug addiction and gambling addiction analogous or homologous? why?
analogous
they share a surface similarity (compulsive behaviour), but do not share a common biological substrate
what did wise & bozarth theory replace?
the older “dependence-withdrawel” theories
how can we differentiate wise & bozarth’s theories
wise & bozarth:
-theories about positive reinforcement
-the drug has qualities that are repeititve
drug-dependence theories:
-were negative reinforcement theories
-the drug overtime produces changes associated with tolerance
-quitting the drug is revealed in withdrawel
-you take drugs to eliminate the negative side effects of withdrawel
what are the drug dependence theories lacking in?
an explanation of why people are abusing SEVERAL different drugs
seperating drug addiction in terms of withdrawel and in terms of a person self-administering the drug (they are not only administering it to reduce the negative side-effects)
Definition of Dependence in drug dependence theories?
Non-Circular
-Defined in Terms that are Separate from Compulsive Drug Seeking that Identifies Addiction
-Explain drug addiction in terms of withdrawel
according to the drug dependence theory, drug taking is motivated by…
by the Need to Alleviate or Avoid Withdrawal Distress
what are wise & bozarth’s critiques of the drug dependence theory?
- relieving withdrawal distress is not wholly effective in treating addiction
-detoxification from the drug is not an effective treatment, people may turn back to drugs once they leave - the dependence/withdrawel associated with different drugs is not all the same (not homologous)
- stimulants are not associated with a recognizable PHYSICAL dependence syndrome
-not even comparable to the physical dependence posited by opiods - the initial use of drugs is not brought about as a result of physical dependence
-what motivates use up until the point of tolerance and withdrawel?
-what would compel someone? - No less likely to become abstinent of drugs that produce minimal/none withdrawel symptoms
-they may self-administer even when withdrawel symptoms are very low
-example: stress may cause people to re-initiate use - many drugs associated with severe abstinence are not associated with addiction
-example: drugs used to treat hypertension may make you very ill with withdrawel
The Prototype Case involving Opiates showed that opiate Physical Dependence and Opiate Reinforcement are
Two Independent Phenomenon Involving Two Independent Brain Mechanisms
Negative versus Positive Reinforcement?
negative: terminating a state or avoiding a condition which increases the likelihood of the desired outcome (dependent and withdrawal theories)
positive: rewarding outcomes brought about by intaking the drug
-reinforcing because of the states that they induce
-DOES NOT MEAN that it is homologous with “euphoria” or “pleasure”
