psyc 3590: drugs and behaviour test 1

drug

non-food substance that chemically alters a living organism

including:

• arbitrary dood/drug distinction

• something that people consume for chemical benefits

psychoactive drugs

has an effect on the central nervous system

• drugs that you can ‘feel’

  • changes in mood, cognition and or behaviour

substance

things not typically thought of as a drug

• example: alcohol

illicit drugs

illegal drugs

issues of illicit drugs

• can change over time

• not correlated with legality or addiction

  • example: weed, edibles no longer illegal

drug misuse

using in a way that leads to harm and problems

• physical health

• mental health

• social/ interpersonal difficulties

• risky behaviour

addiction

someone who becomes dependent on a drug

drug abuser/ user

stigmatizing

• we used to use this however we now use drug misuse

• be mindful of the words we choose as society has a way of looking down on others, and making them feel bad about themselves

• separate the person from the behaviour

• use terms such as : people who use drugs instead

learning theories of drug use

• classical conditioning of craving

• operant conditioning and drug use

• social learning theory

*review notes, and q-cards*

biopsychosocial model

facts that influence drug use change over time

• biological factors

• psychological factors

• social/ environmental factors

*review notes, and q-cards*

epidemiology

study of drug use

• study of incidence, prevalence, trends, distribution, and how it correlates to drug use and associated conditions

why is epidemiology important

• resource allocation

• track and respond epidemics

• understand impacts of policies and programs

epidemiology methods

• surveys

• sales data

• administrative data

• waste-water analysis

• biological sample collection

what is NOT addictive behaviour?

• morning coffee

• social drinking

• occasional cannabis use

• experimenting with shrooms

physical dependence

when a person’s body/brain needs the drug

tolerance

need more of a drug to get the same effect overtime

withdrawal

unpleasant symptoms experienced when stopping/cutting down after a prolonged period of use

psychological dependence

emotional/ mental need for a drug

• compulsive use

• inability to control use

• craving/urge to use

• relapse after topping

  • example: snoop dogg

substance use disorder - dsm 5

problematic pattern of substance use leading to clinically significant impairment or distress

• two or more symptoms in a 12 month period

addiction

a chronic relapsing condition characterized by compulsive drug seeking and abuse by long-lasting changes in the brain

components of nervous system

• somatic nervous system

• autonomic nervous system

• central nervous system

somatic nervous system

• sensory neuros, movement

  • not as relevant

autonomic nervous system

• parasympathetic

• sympathetic

central nervous system

• brain

• spinal cord

limbic system

important for emotion, memory, reward/learing

includes:

• amygdala, nucleus accumbens, hippocampus, thalamus, hypothalamus

dopamine

many drugs are thought to be reinforcing and habit forming because of action and dopamine systems

major functions:

• reward

• motivation

• pleasure

• compulsion

serotonin

many antidepressant drugs are thought to exert mood effects through serotonin pathways

major functions:

• mood regulation

• memory processing

• sleep

• cognition → alertness, attention, concentration

norepinephrine

stimulant drugs may have impact on attention and wakefulness through NE pathways

major functions

• arousal

• attentiveness

• wakefulness

• food intake

GABA & glutamate

exert function generalized excitatory inhibitory functions throughout the brain

glutamate - exciatory function

stimulant of glutamate receptors increases the activity of neuron

gaba - inhibitory function

stimulation functions of gaba receptors decreases activity of neuron

• many sedatives work by enhancing gaba activity such as alcohol, opioids, nicotine — they block gaba activity in the vta

pharmacology

broad study of drugs, properties, sources, actions, and effects

pharmacodynamics

the action of drugs (interactions with receptors) and effects of drugs resulting in (behaviour, cognition, and emotional changes)

tolerance

reduced effect at same dose

withdrawal

characteristics symptoms that develop when cutting down or stopping drug after prolonged use

overdose

aversive symptoms developing at high doses of drug that may require medical attention

drug categories

• stimulants

• depressants

• opioids

• hallucinogens

stimulants

alertness, excitation, euphoria, mania/paranoia

depressants

relaxation, disinhibition, sedation, impaired, coordination, impulsivity/recklessness, memory impairment

opioids

relaxation, dream-like state, pain relief, sedation (high doses)

hallucinogens

altered perceptions, hallucinations, emotional change 

stimulant characteristics

intoxication: alert, excited, euphoric mood

withdrawal: fatigue, apathy, depressed mood

depressants characteristics

intoxication: sedation, relaxation/sleep

withdrawal: anxiety, insomina

placebo

inactive substance that taker believes to be a drug

potency

the amount of the drug needed to produce a specific effect (threshold dose)

• NOT how strong drug is

potent drugs

smaller amounts needed to produce effect

pharmacokinetics

how drugs move through the body

• ADME (absorption, distribution, metabolism, elimination)

absorption

process by which drugs move through the body

• route administration is key to determine how quickly drug absorbs into bloodstream

  • injection & inhalation → most rapid

  • intranasal (snorting) → rapid

  • oral & topical → much slower

distribution

movement of drugs throughout tissues in body

• for a drug to affect the brain it must cross the blood-brain carrier

  • semipermeable structure that allows molecules to enter/ not enter the brain

  • some drugs attach to the proteins in the brain which can slow down the process of drugs entering the brain

    • example: thc vs. alcohol

elimination

removal of drug and metabolism from body

metabolism

process by which drug is broken down

elimination & metabolism (ME)

how drugs stop having an effect on the body

• excretion: removed unchanged from body typically via urine

  • process can eventually lead to kidney and liver problems if they ar overworked when metabolizing drugs

pharmacokinetics tolerance

drugs disposition tolerance — this happens has a result from increased activity in liver enzymes & changes in the liver

behavioural tolerance

caused by learned adaptations

• example: being able to walk properly when drunk

pharmacodynamic tolerance

changes in the sensitivity of brain neurone, other neuroadaptions

alcohol

ethanol

• formed by fermentation when yeasts act on sugars to produce ethanol

proof

twice the alcoholic content of beverage

• example: 80 proff = 40% alcohol

prohibition

made alcohol illegal, 18th amendment and volstead act (1900s)

standard drinks

• Canada/US: 14g of ethanol

• 350ml (12oz) bottle/can of beer (5%)

• 142ml (5oz) class of wine (12%)

• 43ml (1.5oz) shot of hard liquor (40%)

absorption - alcohol pharmacology

• 5% mouth

• 25% stomach

• 70% small intestine

  • 30 minutes on a empty stomach

  • 60 minutes+ on a full stomach

distribution - alcohol pharmacology

bloodstream (pumped by heart), and carriers ethanol to all parts of the body

• brain, heart, liver

• distributed to water compartments of body

• does not distribute to body fat easily

• tissues with a lot of blood supply receive alcohol faster

metabolism/elimination - alcohol pharmacology

liver → cleans our blood

• it oxidizes alcohol at a constant rate

• the only way for your BAC to remain low is if you drink alcohol at a slower rate

• small amounts of alcohol are eliminated through urine and sweat

• bac does not decrease by eating or drinking water

blood alcohol concentration (bac)

concentration of alcohol by weight in a volume of blood

• 0.08/100mL = 0.08 BAC → legal limit

factors affecting BAC

• beverage characteristics

  • spirit

  • wine

  • beer

• individual characteristics

  • stomach enviornment

  • body weight

  • body fat %

  • sex

behavioural effects of alcohol consumption

• loss of motor control

• changes in speech

• decrease in cognitive abilities

• impaired judgement

  • small amounts of alcohol will affect cerebral cortex

  • larger doses effect midbrain → sulluring speech

  • even larger amounts affect pons, medulla → breathing

alcohols effect on neurotransmitters

• increases release of dopamine

• increases release of serotonin

• increases release of endogenous opioids (endorphins, enkephalins)

• increases GABA receptor functioning

• decreases glutamate receptor functioning

alcohol myopia

nearsightedness in a psychological sense → poor decision making

endogenous opioids

act on the same receptors of opiate drugs

• alcohol increases release of endorphins and enkephalins

• associated with euphoria and anxiety