Neurotransmission The process whereby neurons communicate with each other Neurotransmission, especially in the brain and spinal cord, helps explain the effects of psychoactive drugs. Psychoactive drugs interfere with normal neurotransmission.
Neurotransmitters Chemical messengers that cross synaptic gaps between neurons When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, setting up the next link in the chain of communication.
Synapse The junction between the tip of the sending neuron and the receptor sites on the receiving neuron Call the synaptic gap or cleft
Five Psychoactive Drug Categories Five different categories we will study: –Depressants –Opiates –Stimulants –Hallucinogens –Marijuana
Drug Classifications: Depressants Module 22: Drugs
Depressants Drugs that reduce neural activity and slow body functioning Includes alcohol and sedatives
Alcohol (ethyl alcohol) Found in beer, wine, and liquor The second most used psychoactive drug (caffeine first) Slows thinking, and impairs physical activity
Blood Alcohol Content (BAC) A measure of how much alcohol is in a person’s bloodstream BAC of.8 considered legal intoxication in most states
Euphoric Affects of Alcohol Alcohol impairs the parts of the brain responsible for controlling inhibitions and making judgments
Alcohol, Memory, and Sleep Studies have shown that alcohol impairs memory by suppressing the processing of events into long term memory. Alcohol impairs REM sleep, further disrupting memory storage.
Alcoholism and Heredity Play “Alcohol Addiction: Hereditary Factors” (11:40) Segment #29 from The Mind: Psychology Teaching Modules (2 nd edition).
Sedatives Drugs that reduce anxiety or induce sleep Also called tranquilizers Include barbiturates and benzodiazepines
Barbiturates Drugs that depress the activity of the central nervous system and thereby reduce anxiety Can be lethal in overdose and interact with other drugs, especially alcohol Impair both memory and judgment Can create tolerance and dependence
Benzodiazepines Drugs that depress that activity of the central nervous system without most of the side effects associated with barbiturates Include Valium and Xanax Can create dependency
Addiction and Depressants Play “Depressants and Their Addictive Effect on the Brain” (4:24) Segment #22 from The Mind: Psychology Teaching Modules (2 nd edition).
Opiates Drugs that depress neural activity, temporarily lesson pain and anxiety Include: opium, morphine, and heroin
Morphine Strong sedative and pain-relieving drug derived from opium Works by preventing pain neurons from firing or releasing pain-signaling neurotransmitters into the synapse
Endorphins Natural, opiate-like neurotransmitters linked to pain control and to pleasure Body’s natural pain killers
Endorphins Play “Endorphins: The Brain’s Natural Morphine” (5:01) Segment #5 from The Mind: Psychology Teaching Modules (2 nd edition).
Drug Classifications: Stimulants Module 22: Drugs
Stimulants Drugs that excite neural activity and speed up body functions Include: caffeine, nicotine, amphetamines, and cocaine
Caffeine Stimulant found in coffee, chocolate, tea, and some soft drinks Provides user with a sense of increased energy, mental alertness, and forced wakefulness Blocks neurological receptor sites that, if activated, sedate the central nervous system
Nicotine Stimulant found in tobacco Effects similar to those of caffeine Very addictive and does not stay in the body very long
Cocaine Stimulant derived from leaves of the coca plant Crack – cocaine crystals Blocks the reuptake of certain neurotransmitters Dependency is quick and severe; places extreme strain on cardiovascular system
Amphetamines Drugs that stimulate neural activity, speeding up body functions, with associated energy and mood changes Includes: speed, uppers, and methamphetamines Mimic adrenaline Can cause irreversible changes in mood
Drug Classifications: Hallucinogens Module 22: Drugs
Hallucinogens Drugs that distort perceptions and evoke sensory images in the absence of sensory input Include: LSD and ecstasy Sometimes called “psychedelics”
Lysergic Acid Diethylamide (LSD) Powerful hallucinogenic drug Also known as “acid” The effects vary from person to person Users can be dangerous to themselves and others.
Ecstasy Hallucinogenic drug that produces lower inhibitions, pleasant feelings, and greater acceptance of others Also called MDMA Even moderate users may experience permanent brain damage.
Drug Classifications: Marijuana Module 22: Drugs
Marijuana Leaves, stems, resin, and flowers form the hemp plant that, when smoked, lower inhibitions and produce feelings of relaxation and mild euphoria THC (delta-9-tetrahydrocannabinol) is the active ingredient Disrupts memory; lung damage from smoke