Ap Psych Unit 1 1.3 C: Psychoactive Drugs

Psychoactive Drug

a chemical substance that acts on the brain to impact behavior, perceptions, moods, or mental processes

Blood-brain barrier (BBB)

blocks certain material in the blood from entering brain tissues

-> semi permeable membrane between blood and interstitial of brain

Substance use disorders

the persistent use of drugs despite substantial harm and adverse consequences to self and others

Characteristics of dependence

tolerance, addiction, physical dependence, psychological dependence, withdrawal

Tolerance

results in the need for greater amount of the drug to experience initial effects

Addiction

state of psychological and or physical dependence on drugs or other substances

Physical dependence

user has intense cravings and a biological need for the drug

- need to alleviate pain

Psychological dependence

spend time thinking about next high

- need to use drug for relieving mental stress

Withdrawal

painful side effects that occur after the end of long term use

- body may produce less neurotransmitters that were supplemented by the drug

Depressants

slow nervous system activity

ex: alcohol, barbiturates, opiates

Alcohol

acts as a depressant on the frontal lobe reducing inhibitions and slurred speech (Broca's area)

- GABA agonist (mimics GABA)

Barbiturates

Downers, GABA agonist

- often used to treat insomnia, can interfere with sleep patterns and cause dependence

Opiates

suppress pain and induce sleep while also producing a sate of euphoria

ex: opium, morphine, oxycodone, heroine

- endorphins agonist

Hallucinogens

alter one's perceptions, causing dramatic hallucinations

ex: LSD, PCP, THC (marijuana), MDMA (ecstasy)

LSD

produces hallucination and delusions similar to a psychotic state

- can result in psychosis, memory loss, paranoia, panic attacks, nightmares and aggression

THC

the active ingredient in marijuana, produces mild hallucinations, euphoria, relaxation

-long term use can shrink areas of the brain associated with memory and emotions

-cannabinoid agonist

Stimulants

activate the nervous system and essentially increase levels of arousal and activity while suppressing appetite

-ex: nicotine (tobacco), caffeine, cocaine, amphetamines

Caffeine

increases alertness, can cause anxiety, heart palpitations, insomnia, and diarrhea

Nicotine

Acetylcholine agonist, boosts release of dopamine

arousal - boosts alertness and mental efficiency

calming effect - reduces anxiety and sensitivity to pain

Amphetamines

chemically similar to epinephrine, increased alertness and sense of well-being

-can cause euphoria followed by a crash of severe depression

MDMA (ecstacy)

stimulant and mild hallucinogen

- produces a euphoric high and can damage serotonin producing neurons resulting in a permanent deflation of mood and impairment of memory

Cocaine

- blocks reabsorption of dopamine (dopamine agonist)

- produces increased alertness, motivation, and euphoria

- crash leads to depression, anxiety, and strong cravings

Substance use vs abuse

use = using a substance that does not yet interfere with a person's life

abuse = pattern of drug use that diminishes one's ability to fulfill responsibilities

Dependence Criteria

Need 4 out of 7

- developing a tolerance

- experiencing withdrawal

- using for longer period or in greater quantities than needed

- presence of a desire or repeated attempts to cut back on use

- spending a lot of time obtaining/using substance

- reduction/cessation of usual activities

- repeated use despite knowing it causes harm