Download - Drugs and Consciousness
Drugs and ConsciousnessPsychoactive Drugs: A chemical
substance that alters perceptions and moods (affects consciousness).
Dependence and AddictionContinued use of a psychoactive drug
produces tolerance. With repeated
exposure to a drug, the drug’s effect lessens. Thus it takes greater
quantities to get the desired effect.
Withdrawal and Dependence1. Withdrawal: Upon stopping use of a
drug (after addiction), users may experience the undesirable effects of withdrawal.
2. Dependence: Absence of a drug may lead to a feeling of physical pain, intense cravings (physical dependence), and negative emotions (psychological dependence).
Misconceptions about AddictionAddiction is a craving for a chemical
substance, despite its adverse consequences (physical & psychological).
1. Addictive drugs quickly corrupt.
2. Addiction cannot be overcome voluntarily.
3. Addiction is no different than repetitive pleasure-seeking behaviors.
Psychoactive DrugsPsychoactive drugs are divided into three
groups.1. Depressants 2. Stimulants3. Hallucinoge
ns
DepressantsDepressants are drugs that reduce neural
activity and slow body functions. They include:
1. Alcohol 2. Barbiturat
es3. Opiates
Alcohol1. Alcohol affects motor skills, judgment,
and memory…and increases aggressiveness while reducing self awareness.
Drinking and Driving
Stages of Alcohol Intoxication1. Subclinical (0.01-0.05)- Nearly normal behavior
2. Euphoria (0.03-0.12)- Mild euphoria, sociability, increased self-confidence; decreased inhibitionsdiminution of attention, judgment and control
3. Excitement (0.09-0.25)- Emotional instability; loss of critical judgment, impairment of perception, memory and comprehension, reduced visual acuity; peripheral vision and glare recovery, sensory-motor incoordination; impaired balance, drowsiness
Stages of Alcohol Intoxication4. Confusion (0.18-0.30)- Disorientation, mental
confusion; dizziness, exaggerated emotional states, disturbances of vision and of perception of color, form, motion and dimensions, increased pain threshold, increased muscular in-coordination; staggering gait; slurred speech, apathy, lethargy
5. Stupor (0.25-0.40)- General inertia; approaching loss of motor functions, markedly decreased response to stimuli,marked muscular incoordination; inability to stand or walkvomiting; incontinence, impaired consciousness; sleep
Stages of Alcohol IntoxicationComa (0.35-0.50)- Complete
unconsciousness, depressed or abolished reflexes, subnormal body temperature, incontinence, impairment of circulation and respiration, possible death
Death (0.45 +)- Death from respiratory arrest
BAC CalculationsBAC Depends on:
1.# of Drinks
2.Type of Drink
3.Weight
4.Amount of Time Drinking
5.http://www.ou.edu/oupd/bac.htm
BarbituratesBarbiturates: Drugs that depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment. Nembutal, Seconal, and Amytal are some examples.
Effects of Barbiturates on the BrainExact mechanisms not understood
Thought to bind to sodium channels on neurons and prevent the flow of sodium ions. Because sodium ions cannot flow across the neuronal membrane, action potentials cannot be produced.
May also increase flow of chloride ions affecting GABA
Interesting Barbiturate Facts The barbiturate called sodium
pentothal is known as "truth serum." However, it really does NOT cause people to tell the truth. Rather, it may lower a person's inhibitions and make people more talkative.
Musician Jimi Hendrix died on September 18, 1970 of a barbiturate overdose. Marilyn Monroe also met the same fate.
Opiates
3. Opiates: Opium and its derivatives (morphine and heroin) depress neural activity, temporarily lessening pain and anxiety. They are highly addictive.
OpiatesPlaces on neurons recognize opiates. These
receptors are located in parts of the brain important for breathing, pain, and emotions.
The brain manufactures its own opiates known as endorphins.
Long history of opium use in medical field
Opiate HistoryImportant Dates in the History of Opiates1803 - Morphine was isolated from opium by Frederick
Serturner. 1832 - Codeine was extracted from opium. 1874 - Heroin was first produced from morphine.1898 - The Bayer Company introduced heroin as a substitute for morphine.1914 - Harrison Narcotic Act - Added a tax on opiate distribution.1922 - Narcotic Import and Export Act - Restricted the importation of crude opium except for medical use.1924 - Heroin Act - Made manufacture and possession of heroin illegal.1930 - Federal Bureau of Narcotics was created.1970 - Controlled Substances Act was passed - Divided drugs into categories, set regulations and penalties for narcotics.
Heroin Effects on the Brain Stimulates a "pleasure system" in the brain
involving neurons in the midbrain that use the neurotransmitter called "dopamine."
Midbrain dopamine neurons project to the cerebral cortex causing the pleasurable effects of heroin and adding to the addictive power.
Other neurotransmitter systems, such as those related to endorphins also likely to be involved with withdrawal from and tolerance to heroin.
Famous Opiate AbusersJohn Belushi (Death)Kurt Cobain (Death)Jerry Garcia (Death)Edgar Allen PoeMarilyn Monroe
(Death)Anna Nicole Smith
(Death)John Candy (Death)Ben FranklinRobert Downey Jr.
Boy GeorgeElvis Presley (Death)Jim Morrison (Death)Tom SizemoreSid Vicious (Death)Keith RichardsDJ AM (Death)Heath Ledger (Death)Chris Farley (Death)Janis Joplin (Death)
StimulantsStimulants are drugs that excite neural activity and speed up body functions.
1. Caffeine2. Nicotine3. Cocaine4. Ecstasy5. Amphetamines6. Methamphetami
nes
Caffeine and NicotineCaffeine and nicotine increase heart and
breathing rates and other autonomic functions to provide energy.
AmphetaminesAmphetamines stimulate neural activity, causing accelerated body functions and associated energy
and mood changes, with devastating effects.
Amphetamine Effects on BrainCause release of dopamine from axon
terminals. Block dopamine reuptake. Inhibit storage of dopamine in vesicles. Inhibit destruction of dopamine by enzymes. Actions result in more dopamine in the
synaptic cleft where it can act on receptors.
Results of Amphetamine UseInsomnia, restlessness "Paranoid psychosis" Hallucinations Violent and aggressive behavior Weight loss Tremors
Crystal MethHighly addictive amphetamine with effects
similar to cocaine.Synthetic (manmade) drug, manufactured
locally using pseudo-ephedrine (ingredient in cold medications), acetone, drain cleaner, lithium, iodine, paint thinner, kerosene.
Damage to the brain is similar to that caused by strokes or Alzheimer’s disease.
20% of people who use meth become dependent.
EcstasyEcstasy or (MDMA) -
Stimulant and mild hallucinogen.
Produces euphoric high Can damage serotonin-
producing neurons, resulting in permanent
deflation of mood and impairment of memory.
CocaineCocaine induces immediate euphoria followed by a
crash. Crack, a form of cocaine, can be smoked. Other forms of cocaine can be sniffed or injected.
Long Term Effects of CocaineDizziness Headache Movement problems Anxiety Insomnia Depression Hallucinations
Hallucinogens
Hallucinogens are psychedelic (mind-manifesting) drugs
that distort perceptions and evoke sensory images in the
absence of sensory input.
LSD1. LSD: (lysergic acid diethylamide)-
chemical that alters a user's mood, thoughts or perceptions.
2. Thought that effects of LSD caused by stimulation of serotonin receptors on neurons in brain area called the raphe nuclei. Not clear what produces all the effects of LSD.
3. Mandatory 5 year sentence for possession of 1 gram.
Effects of LSDFeelings of "strangeness" Vivid colors Hallucinations Confusion, panic, psychosis, anxiety Emotional reactions like fear, happiness or
sadness Distortion of the senses and of time and space "Flashback" reactions - these are the effects of
LSD that occur even after the user has not taken LSD for months or even years.
Increases in heart rate and blood pressure Chills Muscle weakness
MushroomsPsilocybin Mushrooms: produce s yawning,
inability to concentrate, restlessness, increased heart rate, and hallucinations (visual and auditory
Amanita Muscaria: produces feelings of euphoria, hallucinations, muscle jerks, drowsiness, sweating, pupil dilation, and increased body temperature. Toxic to kidneys and liver.
Mushrooms Effects on BrainChemical structure similar to serotonin
Primary effect of psilocin is on seratonin receptors.
Reduces reuptake of serotonin by neurons .
Muscimol activates GABA receptors on neurons- inhibitory system
MushroomsIdentification of hallucinogenic mushrooms can
be difficult because they look similar to toxic, deadly mushrooms.
Mushrooms bought from dealers may be contaminated with drugs such as LSD or PCP
In 1998 in the United States, 9,839 cases of mushroom poisoning were reported by poison centers
"All mushrooms are edible, but some only once."-- Croatian Proverb
PCPPhencyclidine- affects multiple neurotransmitter
systems in the brain: inhibits reuptake of dopamine, norepinephrine, serotonin, and inhibits action of glutamate.
Dissociative anesthetic because users appear to be "disconnected" from their environment: they know where they are, but they do not feel as if they are part of it = violent/aggressive behavior
Can act like many other classes of drugs depending on user and administration
CannabinoidsMarijuana (Cannabis sativa)
THC (delta-9-tetrahydrocannabinol): is the major active ingredient in marijuana (hemp plant) that triggers a variety of effects, including mild hallucinations.
Marijuana Effects on BrainTHC acts on cannabinoid receptors on
neurons in brain.
Brain areas involved in memory, concentration, perception, movement.
Impairs with normal functioning of these areas of the brain.
Marijuana Effects on the BrainAnandamide is the brain's own THC (just like
"endorphin" is the brain's own morphine).
THC can affect two neurotransmitters: norepinephrine and dopamine. Serotonin and GABA levels may also be altered.
Addiction/Death?Addiction is controversial. Also controversial is whether marijuana
causes long-term mental abnormalities. Future research needed.NO documented cases of a fatal overdose
produced by marijuana. High level of tar and other chemicals in
marijuana; smoking marijuana increases the chances of lung problems and cancer later in life.
How long does marijuana stay?Marijuana can be detected in urine, blood,
saliva, and hair follicles.
Depends on how much a person has smoked, how long a person has smoked for, and the method used to detect THC.
The half-life of THC is about 24 hours. However, the metabolites of THC can be detected for 45 to 60 days after the last use.
Drug UseThe graph below shows the percentage of
US high- school seniors reporting their use of alcohol, marijuana, and cocaine
from the 70s to the late 90s.
Influences on Drug UseThe use of drugs is based on biological,
psychological, and social-cultural influences.
Marijuana UseThe use of marijuana in teenagers is directly related to the “perceived risk”
involved with the drug.
Near-Death ExperiencesAfter a close brush with
death, many people report an experience of moving through a dark tunnel with a light at the end. Under the
influence of hallucinogens, others report bright lights at
the center of their field of vision.
Mind-Body ProblemNear-death experiences raise the mind-body
issue. Can the mind survive the dying body?
1. Dualism: Dualists believe that mind (non-physical) and body (physical) are two distinct entities that interact.
2. Monism: Monists believe that mind and body are different aspects of the same thing.