Psychoactive drugs

Blood-Brain Barrier

a border of blood vessels in the brain that prevents (most) substances in the blood in the rest of our body from getting into our central nervous system

Psychoactive drugs

traverse the blood-brain barrier, where they interact with neurotransmitters at the receptor sites, altering mood and perception

Tolerance

brain chemistry adapts to drug, lessening the effect

• leads to people seeking larger quantities to get the same effect

• increases addiction risk

• developed by repeatedly exposing to drug

Addiction

when a user becomes physically dependent on drug

Physical dependence

with increasing doses, the body becomes used to/dependent on substance because of the decreased production of neurotransmitters affect by drug

• can cause physical withdrawals

Physical Withdrawal

Fatigue, tremors, headache, nausea/vomiting, death

Stimulants

increases behavioral/mental activity

• heighten activity in central nervous system

• activate sympathetic nervous system —> increasing heart rate and blood pressure

• improves mood, keeps awake, makes you restless

• increases concentration

• reduces hyperactivity in ADHD people

Caffeine

• mild stimulant —> increases attentiveness and improves mood

• physically addictive —> withdrawal symptoms

• high doses —→ anxiety, insomnia, rapid heart rate

• activate glutamate (excitatory neurotransmitter) and inhibits GABA (inhibitory neurotransmitter)

Cocaine

• agonists for dopamine- reputake inhibitory by increasing dopamine

• activates reward centers

• boosts self-confidence, creates euphoria and fidgetiness

• can lead to paranoia and psychosis

Reuptake inhibitor

prevents reuptake

reward centers

areas of the brain involved in pleasure

Depressants

opposite of stimulants, decreases behavioral/mental activity, depressing central nervous system

Alcohol

• loosens inhibitions by depressing neural activity that controls self-monitoring of thoughts and behaviors

• small amounts can reduce anxiety

• large amounts: slow reaction time, slurred speech, memory disruption

• activates GABA receptors

• long time to metabolize

Opioids

• mimics endorphins —> euphoria, relaxation, pleasure

• prescribed as painkillers

• no change in cognitive abilities

• highly addictive —> overdose deaths

Heroin

What is the most common opioid?

Hallucinogens

produces change in consciousness by altering perception, creating hallucinations, and blurring the boundaries between the self and external world

operates on serotonin receptor sites

Marijuana/Cannabis

• qualities of hallucinogen, stimulant, and depressants

• small doses cause a mild high

• large doses causes hallucinogenic reactions

• altered perception, sedation, pain relief, anxiety, euphoria, distortions

• psychologically addictive