Ap Psychology: Drugs & Neurotransmitters

psychoactive drugs

a chemical substance that alters perceptions and moods

neuroadaptaion

the brain's chemistry adaptation to offset the drug's effect

tolerance

the diminishing effects with regular use of the same drug requiring the user to take larger doses before experiencing the drug;s effect

addiction

a compulsive craving for a substance despite adverse consequences

withdrawal

the discomfort and distress following the discontinuing use of an addictive drug

psychological dependence

a psychological need for a drug to relieve negative emotions such as stress

drugs that are psychologically dependent

cocaine, alcohol, meth, amphetamines, smoking

physical dependence

a physiological need for a drug to relieve negative emotions such as stress

drugs that are physically dependent

alcohol, opiates (heroin and morphine), barbiturates, nicotine, meth, amphetamines

depressants

drugs that reduce neural activity and slow body functions

drugs that are depressants

alcohol, barbiturates, opiates,

stimulants

drugs that excite neural activity and speed up body functions

drugs that are stimulants

amphetamines, methamphetamine, cocaine, nicotine, ecstasy

hallucinogens

psychedelic "mind-manifesting" drugs that distort perceptions and evoke sensory images in the absence of sensory input

drugs that are hallucinogens

LSD, marijuana, ecstasy (mildly)

alcohol

-affects the parts of the brain that help make decisions, involve impulse control, and memory

-binds with GABA receptors making them more inhibitory, and it binds to glutamate preventing it from exciting the cell

-also affects dopamine

barbiturates

drugs/tranquilizers that depress the central nervous system activity reducing anxiety and impairing memory and judgement

-nembutal, seconal, amytal,

-affects GABA

opiates

opium and its derivatives (morphine and heroin) which depresses neural activity, lessening pain and anxiety temporarily

-affect natural opiates (endorphins)

heroin

-mimics natural opiates

-binds to opiate receptor sites turning off dopamine inhibition

-dopamine overstimulates cells which results in feelings of well-being and sedation

amphetamines

drugs that stimulate neural activity causing body functions and associated mood and energy changes to speed up

-affects dopamine

methamphetamine

a powerfully addictive drug that stimulates the nervous system, which speeds up body functions and associated mood and energy changes

-overtime it reduces baseline dopamine levels

crystal meth

the crystalized form of methamphetamine that is also highly addictive

cocaine

a psychoactive drug that is used for its euphoric effects

-depletes brain's supply of dopamine, serotonin, and norepinephrine

-users become fidgety because it concentrates in the brain that controls voluntary movements

nicotine

-triggers the release of norepinephrine and epinephrine which diminish appetite, boost alertness and mental efficiency

-stimulates CNS to release dopamine and opiates

-also affects ACh

insula

part of the brian in the frontal lobes that lights up when people crave drugs

ecstasy (MDMA)

a synthetic stimulant drug and mild hallucinogen

-mimics serotonin, taken up by its transporters. excess serotonin in the synaptic gap binds repeatedly to the receptor sites overstimulating the cells

-results in feelings of emotional elevation and connectedness with those around them "hug drug"

LSD (Lysergic acid diethylamide)

a powerful hallucinogenic drug that causes feelings of euphoria, detachment and panic

-affects serotonin

marijuana

leaves and flowers of the hemp plant

THC

main active ingredient in marijuana that triggers a variety of effects including hallucinations

-molecules bind to cannabinoid receptor sites which turn off the release of inhibitory neurotransmitters so dopamine can be released freely

amplifies sensitivity to colors, sounds tastes, and smells

misconceptions about addiction

1) addictive drugs quickly corrupt

2) addictions cannot be overcome voluntarily

3) the concept of addiction can be extended to cover other behaviors

Dopamine

-associated with pleasure, addiction

-rewards our brains when we do something adaptive

-controls voluntary movements

-influences learning, attention, alertness, emotion

Serotonin

-feelings of calmness and satiation

-affects hunger, emotions, and moods (HEM)

-regulates sleep, pain, arousal, dreaming (SPAD)

-involved in perception

GABA

primary inhibitory neurotransmitter; reduces anxiety

Acetylcholine (ACh)

-regulates movement

-involved in some kinds of learning and memory

Epinephrine

-aka adrenaline: hormone which is excitatory

-activates a sympathetic nervous system by making the heart beat faster, stopping digestion, enlarging pupils, sending sugar into the bloodstream, preparing a blood clot faster

Norepinephrine

-aka noradrenaline: chemical which is excitatory

-used in ANS and most regions of the brain

-regulates alertness, arousal,

-affects heart rate, memory, sleep, stress, sexual responsiveness, vigilance, appetite,

Endorphins

-pleasurable sensations (enhances the release of dopamine)

-controls pain

Glutamate

primary excitatory neurotransmitter; involved in learning and memory

antagonists

drugs that block the function of a neurotransmitter

agonists

drugs that increase the action of a neurotransmitter

Too much Dopamine

Schizophrenia

Too little Dopamine

Parkinson's, ADHD, Tourette's

Too much Serotonin

reduced hunger and sex drive

Too little Serotonin

depression, OCD, aggressive behaviors, trouble sleeping, some anxiety disorders

Too much GABA

super relaxed

Too little GABA

anxiety, insomnia, eating disorders, seizures or tremors

Too much ACh

contraction of muscles (from the venom of a black widow spider's bite)

Too little ACh

Alzheimer's, paralysis (if shot with curare)

Too much Norepinephrine

agitation, elevated mood and arousal, high blood pressure

Too little Norepinephrine

depression

Too many Endorphins

euphoric feelings (in case of opiate use)

Too few Endorphins

causes discomfort, grumpiness

Too much Glutamate

can cause brain damage (i.e. after a stroke)

effects of alcohol

disinhibition, slowed neural processing, memory disruption, cognition-brain shrinkage, reduced self-awareness/control, expectancy effects, sexual situations