Unit 1: Historical Foundations, Biology of Addiction, Drug Classes, and Behavioral Understanding

What characteristics differentiate addiction from regular use of a drug?

chronic use compulsive drug-seeking use despite harmful consequences

Is addiction a medical diagnosis? If not, what is the term used to medically diagnose drug problems?

it is NOT a medical diagnosiscalled "substance use disorder" in the DSM 5

What does it mean when someone says that addiction is a brain disease?

because changes in brain structure + function are fundamental to the development and expression of addiction

prevalence

the proportion of persons who have a condition at / during a particular time period

incidence

the proportion / rate of persons who develop a condition during a particular time

morbidity

the condition of having a disease, illness, or other health problemthe presence + burden of sickness / injury in a population

mortality

the state of being subject to death the occurrence of death w/in a population

epidemic

the rapid spread of disease to a large number of hosts in a given population w/in a short period of time

YPL (???)

years of potential life

DALYs

Disability-adjusted life year:

• A measure of the total burden of disease in a population

• Quantifies the number of years of healthy years lost to illness, disability, or premature death

attributable fraction

the proportion of incidents in the population that are attributable to the risk factor

what is the approximate prevalence of Alcohol Use Disorder in US in 2015?

6.20%

what is the approximate lifetime prevalence of Alcohol Use Disorder in the US?

10%

Which drug has highest total costs associated with its use?

tobacco + alcohol 

How do harms and costs associated with legal drugs compare with illegal drugs?

illegal drugs are cheaper but more harmful

What are areas of cost (for example, healthcare costs, lost productivity, legal costs) are associated with illegal drug use?

direct + indirect costs attributable to illicit drug use are estimated in 3 principal areas:crime, health, productivity, healthcare costs, legal costs

Approximately what percentage of deaths worldwide attributable to alcohol?"

6%

percent of accidents and disability worldwide due to alcohol

around 5%

What is person-first language? Why is it important to use respectful terms to describe people with drug and alcohol problems?

a communication style that emphasizes a person's identity before their health condition, disability, or other defining characteristicsto focus on an individual's humanity rather than defining them by a diagnosis like SUD

What are traditionally accepted uses for psychoactive substances?

spriritual, medicinal, therapeutic uses

When and why did availability and potency of drugs change from the 14th to 20th centuries?

in history, availability + potency was limited to geography, scientific knowledge, tech, and sometimes povertyrecreation use of drugs (other than alc, tobacco, marijuana, and caffeine) were mostly unknown til the 19th century + expanded in the 20th

two main models of addiction that have dominated for thousands of years?

moral model disease model

moral model of addiction

• humans are given free will forces of temptation/evil exist to text humans

• a virtuous person abstains from / exerts control over temptation/evil

• a person that does not is seen as weak, spiritual disfavor, evil, etc.

• it is a defect of a person's character for which they are responsible

disease model

views addiction as a primary, chronic brain disorder involving dysfunctional brain circuits,leading to compulsive drug use despite negative consequences

What was the temperance movement in America?

Organized effort to limit or outlaw the consumption and production of alcoholic beverages in the United States

What change to the constitution did the temperance movement produce?

18th amendmentestablished the Prohibition Era by banning the manufacture, sale, and transportation of alcoholic beverages

When was Alcoholics Anonymous founded and by whom?

Bill Wilson and Dr. Bob Smith founded Alcoholics Anonymous in Akron, Ohio in 1935

What influence did the AA model have on the development of the early modern disease model?

popularized the idea that alcoholism is an "illness" rather than a moral failure Jellenick's model

What are the 4 stages of Jellenick's model?

• Pre-Alcoholic

• Early Alcoholic

• Middle Alcoholic

• Late Alcoholic

Jellenick's model: pre-alcoholic

• social drinkingas stage progresses

• drinking is more frequent for stress reduction

• physiological char.: beginnings of tolerance

Jellenick's model: early alcoholic

• growing discomfort w drinking comboed w an inability to resist it

• lying abt drinking to friends/loved ones

• spiking coffee, hiding drinks

• increased tolerance

• increased obsession w thoughts of alcohol first alcohol-related blackout occurs in this stage

Jellenick's model: middle alcoholic

• symptoms become obvious to others

• missing work/social obligations bc of drinking/hangovers

• drinking at inappropriate times (driving, at work, while caring for children)increased irritability + argumentativeness

• facial flush, weight loss/gain, bloating attempts to stop drinking

Jellenick's model: late alcoholic

• serious health problems develop

• everything in life (friends, family, work) take a backseat to drinking

• attempts to stop drinking may be characterized by tremors / hallucinations

• can be helped w therapy, detoxification, and rehabilitation

First psychological models of addiction

• freud: drug use as a coping strategy + form of regression

• behavioral: reinforcement → positive reinforcement at first and then negative reinforcement later along w classically conditioned context effects

Modern disease model

• the idea of addiction as a disease

• IN CONJUNCTION WITH: neuron communication mechanisms + how drugs alter this + behavioral effects caused by the changesreward pathways + how they are affected by the pleasurable sensationst hat drugs produce

Volkow and Li's (2004) v. Armstrong's (2019) models of addiction

• Volkow and Li (2004)

  • focus on neurobiological cycle of drug use frames it as a chronic, relapsing brain disease

• Armstrong (2019)

  • adds an evolutionary + behavioral context to explain why these neurobiological processes are vulnerable to addiction

  • evolutionary: "ancient reward systems" that drugs are satisfied by + ill-equipped to resistsocial attachmentgenetic predisposition

• both

  • recognize addiction as a brain disease involving the cycles of binge / intoxication, withdrawal, and craving

Why was DSM system created in the first place?

designed to get practitioners to use a common set of criteria

How was addiction thought of in the first version of the DSM?

Symptom of an underlying personality disorder

How was addiction thought of in the second version of the DSM?

• More biologically driven

• Symptoms still not clearly delineated

risk factor

a factor that is associated with increased likelihood of developing a SUD

protective factor

a factor that lowers a person's risk of developing a SUB

bronfenbrenner's ecological systems model

• microsystem: social systems closest to individs

• mesosystem: number and strength of interactions BETWEEN microsystems

• exosystem: social systems in which the individual is affected by

• macrosystem: societal blueprints for culture / subculture

How is understanding bronfenbrenner's ecological model important in understanding risk for substances use?

explains how drug addiction is developed + maintained by the interplay of an individual's environments /systems

central nervous system

brain + spinal cord

peripheral nervous system

the sensory + motor neurons that connect the CNS to the rest of the body (nerves)

name all parts of neuron involved in neurotransmitter communication 

• cell nucleus

• dendrite

• soma

• axon

• myelin

• axon terminal

• synapse

what part of the neuron is also called the cell transmitter?

axon

what part of the neuron is also called the cell receivers?

dendrites

resting potential

• 70 millivolts

• inside of cell is negative relative to outside of - neuron

threshold of excitation

• 55 millivolts triggering of action potential

what is the primary anion in neural impulses?

Cl

what are the primary cations in neural impulses?

Na + K

what leads to the release of a NT?

1. action potential travels down neuron + arrives at the axon terminal

2. action potential triggers the opening of voltage-gated Ca2+ channels is triggered

3. Ca2+ flows into the cell in response

4. Ca2+ synaptic vesicles fuse w pre-synaptic membrane

5. NT is released

6. ion channels open when NT bondion flows cause change in postsynaptic cell potential ion channels will close as NT is broken down / taken back up by presynaptic cell

inhibitory NT

discouraging the cell from firing

excitatory NT

encourage cells to fire

major NTs associated with psychological effects

• serotonin

• norepinephrine

• dopamine

• glutamate

• GABA

• acetylcholine

which NTs are found scattered through the brain?

glutamate + GABA

which NTs are found in neural circuits?

• GABA 

• CCK

• epinephrine

what is the primary excitatory neurotransmitter system?

• glutamatergic system: uses glutamate as a primary excitatory NT

• glutamate is most abundant + widely distributed in the CNS

What does the reward circuit do?

collection of brain structures and neural pathways that are responsible for reward-related cognition

primary NT in the reward system

dopamine

where does the reward circuit start and where does it go?

1. ventral tegmental area (VTA)

2. through nucleus accumbens

3. projecting into frontal

pharmocodynamics

the study of how drugs affect the body

pharmacokinetics

the study of the way the body processes + breaks doewn drugs

why is an understanding of both pharmacodynamics and pharmacokinetics important in addiction studies

so that we can understand the effects of a drug

3 R of drug action

1. release

2. receptor binding

3. removal / reuptake

3 R of drug action: release

drugs can increase / decrease NTs release

3 R of drug action: receptor binding

• competitive binding: drugs can bind to the NT receptor and mimic / block NT effects

• non-competitive binding: drugs can bind to an alternate site on the receptor + modify NT effects

3 R of drug action: removal / reuptake

drugs can promote / inhibit the removal of NTs

affinity

a measure of a drug's ability to bind to a given receptor typealso thought of as "stickiness" or preference

efficacy

a measure of a drug's ability to activate a receptor once it binds

ligand

a mlcl that binds to a receptor

selectivity

• "the "pickiness"" of a neuron

• only responds to ligands in particular orientations

agonist

a substance which initiates a physiological response when combined w a receptor

agonist examples

opioids:

• heroin

• fentanyl

• morphine

antagonist

a substance that interferes / inhibits the physiological action of another

antagonist examples

• naloxone

• naltrexone

• atenolol

tolerance

the body getting used to a drug causing a reduction in its effectiveness

why does the body develop a tolerance to a drug?

bc the number of sites/cell receptors that the drug attaches to/affinity between the receptor and drugs decreases

what is the benefit of tolerance?

fewer side effects as your body gets used to the medication

3 mechanism by which tolerance can be developed

• down regulation

• receptor-effector uncoupling

• activation of opponent processes

parts of pharmakokinetics

1. absorption

2. distribution

3. metabolism

4. excretion

how is the duration of drug effects determined

• how fast drug is broken down / removed from synapse

• how quickly it is metabolized + eliminated from bloodstream

why are drugs addictive?

bc they ware rewarding

what parts of the brain are stimulated to give drugs a "special place" in memory and behavior in addiction?

reward system affects

• limbic system

• sensory and motor cortex

• cerebellum

Why does withdrawal occur with some drugs on cessation of long-term use?

Withdrawal worsens addiction because users want to resume taking the drug to the end withdrawal symptoms

What is withdrawal?

the discomfort and distress that follow discontinuing the use of an addictive drug

How are withdrawal effects specifically related to the effects of the drug itself?

sharply reduces the number of dopamine receptors in brain's reward system

What is the most dangerous withdrawal?

alcohol sweating, rapid pulse, tremors of hand, fleeting hallucinations/illusions, insomnia, nausea, vomiting, agitated behavior, anxiety, and possible seizures

When are the Central Nervous System depressants considered sedatives vs hypnotics?

• sedatives: drugs that decrease activity + have a calming/relaxing effect

• hypnotics: drugs used mainly to cause sleep

• DOSE:

  • lower dose = calming

  • higher dose = sleep

psychoactive substance

chemicals that alter a person's mood, level of perception, or brain functioning

alcohol: class of drug

CNS depressant

alcohol: primary NT affected

• increase GABA (inhibitor)

• serotonin (mood + sleep)

• glutamate (memory + blackouts)

alcohol: which R?

• release

• increase GABA (inhibitor) activity

alcohol: agonist / antagonist ?

agonist

alcohol: cross-tolerant drugs?

possibly but probably not

alcohol: primary effects

• at lower BAC lvls: complex + abstract behaviors are disrupted

• at higher BAC levels: simpler behaviors may be affects

alcohol: prod a significant tolerance?

yes

alcohol: withdrawal? symptoms?

• 6-17 Hours: Mild Symptoms

  • Anxiety, irritability, and craving

• 17-48 Hours: Moderate Symptoms

  • Increasing emotional volatility, fatigue, and shakiness

• 48-72 Hours: Severe Symptoms

  • Severe tremors, delirium tremens, and seizures

benzodiazepines: drug class

CNS depressant