Consciousness Body Rhythms Pages 156-160. Consciousness: Body rhythms and mental states chapter 5.
States of Consciousness: Circadian Rhythms, Sleep & Dreams Topic 7.
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Transcript of States of Consciousness: Circadian Rhythms, Sleep & Dreams Topic 7.
States of Consciousness: Circadian Rhythms, Sleep &
Dreams
Topic 7
Topic of focus
Stages of sleep Why do we sleep? Biological clocks Sleep & Consicousness Physiological mechanism of Sleep and waking
Consciousness• Consciousness can take many forms, while other mental processes
occur simultaneously outside our awareness• Consciousness changes in cycles that correspond to our biological
rhythms and the patterns of stimulation in our environment
Everything of which we are aware at any given timeo Thoughtso Feelingso Sensationso External stimuli
Altered State of Consciousnesso Changes in awareness produced by
o Sleepo Meditationo Hypnosiso Drugs
WHY DO WE NEED TO SLEEP?
Why do we sleep?
Recuperation theoriesSleep is needed to restore homeostasisWakefulness causes a deviation from homeostasis
Circadian theoriesSleep is the result of an internal timing mechanismSleep evolved to protect us from the dangers of the
night
Comparative Analysis of Sleep
All mammals and birds do it – must have an important function
Not a special higher-order human function Not necessarily needed in large quantities No clear relationship between species’ sleep
time and activity level
BIOLOGICAL CLOCK
The Influences of Circadian Rhythms
o Environmental Cueso The ebb and flow of circadian rhythms is not strictly
biological; environmental cues also play a part o Bright light
o especially sunlight
o Sleep-wakefulness cycleo Daily fluctuations of body temperature
o Sleep is best when body is at lowest temperature (97-97.5)
The Influences of Circadian Rhythms
o Control of seasonal rhythms o Pineal Gland
o A gland attached to the dorsal tectum; produces melatonin and plays a role in circadian and seasonal rhythms.
o Secretes melatonin from dusk until just before dawno Does not secrete melatonin during daylight hours
o Melatonino A hormone synthesized from serotonin in the pineal gland o Secreted during the night by the pineal body; o Melatonin levels display circadian rhythms controlled by the
SCNo plays a role in circadian and seasonal rhythms.o Melatonin is not a sleep aid, but may be used to shift
circadian rhythms
Disruptions in Circadian RhythmsJet lag
o When traveling, you reach your destination at a time when it is daylight there, but it would have been time to go to sleep at the place you started
o Can produce memory deficits that may be permanent
o Supplemental melatonin has been shown to be an effective treatment for relapses of psychiatric disorders induced by jet lag
o Zeitgebers are accelerated or decelerated
o Research indicates that frequent flyers, such as this airline employee, are just as likely to suffer from jet lag when crossing several time zones as travelers who are on their first inter-continental journey.
Disruptions in Circadian RhythmsShift work
o When people work during the night and sleep during the dayo Shift workers average 2 to 4 hours less sleep than nonshift
workers of the same ageo Subjective night
o The time during a 24-hour period when body temperature is lowest and when the biological clock is telling a person to go to sleep
o During subjective night, energy and efficiency are at their lowest point, reaction time is slowest, productivity is diminished, and industrial accidents are significantly higher Zeitgebers unchanged, but sleep-wake cycle must be altered
o Rotating work schedules forward from days to evenings to nights makes adjustment easier because people find it easier to go to bed later and wake up later than the reverse
o Modafinilo A wakefulness drug that will help people remain alert without the side
effects of stimulants such as caffeine
Can the effects be prevented or minimized?
o Both produce a variety of deficitso Can the effects be prevented or minimized?
Reducing Jet Lag Gradually shift sleep-wake cycle prior to travel Administer post-flight treatments to promote the needed shift
Phase advance following east-bound travel with intense light early in the morning
Hamster studies suggest a good early morning workout may also help
Can the effects be prevented or minimized?
Reducing the Effect of Shift Changes Schedule phase delays, rather than phase advances
Move from current schedule to one that starts later It is easier to stay up later and get up later than to retire and arise earlier
Phase advances are harder, explaining why east-bound travel tends to be more problematic
Shift workers who temporarily reside at their work places, such as workers on offshore oil rigs, appear to adjust more easily to the demands of night work than those who live at home
Exposure to appropriately timed bright light or even light of medium intensity has been found to reset young adults’ biological clocks and improve their performance
The Influences of Circadian RhythmsDisruptions in Circadian Rhythms
o Subjective nighto The time during a 24-hour period when the biological clock is
telling a person to go to sleep.
o Energy and efficiency are at their lowest points
o Reaction time is slowest
o Productivity is diminished
o Industrial accidents are higher
o Daylight savings time in spring is associated with short term 6.5% increase in accidental deaths.
o Work scheduleso Moving work schedules forward from days to evenings to
nights makes adjustment easier
o Rotating shifts every three weeks lessens the effect on sleep
The Influences of Circadian Rhythmso Circadian Rhythm
o A daily rhythmical change in behavior or physiological process.o About a day o Regular fluctuation from high to low points of certain bodily
functions and behaviors
o Sleep debt o Deficiency caused by not getting the amount of sleep that one
requires for optimal functioning
o Affects psychological functions ofo Blood pressureo Heart rateo Appetiteo Secretion of hormones and digestive enzymeso Sensory acuityo Eliminationo Body’s response to medication
The Influences of Circadian Rhythms
o Suprachiasmatic nucleus (SCN)o A nucleus, situated atop the optic chiasm, in the brain’s hypothalamus
that control the timing of circadian rhythmso It contains a biological clock responsible for organizing many of the
body’s circadian rhythms.o Lesions do not reduce sleep time, but they abolish its circadian periodicityo Exhibit activity that can be entrained by the light-dark cycleo Transplant SCN, transplant sleep-wake cycle
o Melanopsino A photopigment present in ganglion cells in the retina whose axons
transmit information to the SCN, the thalamus, and the olivary pretectal nuclei.
o Zeitgeberso A stimulus (usually the light of dawn) that resets the biological clock
responsible for circadian rhythms.o Intergeniculate leaflet (IGL)
o A part of the lateral geniculate nucleus that receives information from the retina and projects to the SCN; terminals release neuropeptide Y at the SCN
Stages of sleep
Sleep
o Understanding of sleep increased by the study ofo Brain waves
o Eye movements
o Chin muscle tension
o Heart rate
o Respiration rate
Electro-oculogram (EOG) An electrical potential from the eyes, recorded by means of electrodes
placed on the skin around them; detects eye movements.
Electromyogram (EMG) An electrical potential recorded from an electrode placed on a muscle.
3 Physiological Measures of Sleep
By means of Electroencephalogram (EEG) “brain waves”
By means of EOGEye movements seen during rapid eye movement
(REM) sleep
By means of EMGLoss of activity in neck muscles during some
sleep stages
SleepPolysomnogram o Provides brain wave sleep recordings
o Outlined REM and NREM sleep patterns
Beta activity Irregular electrical activity of 13–30 Hz recorded from the brain;
generally associated with a state of arousal.
Alpha activity A smooth electrical activity of 8–12 Hz recorded from the brain;
generally associated with a state of relaxation Eyes closed, preparing to sleep
Theta activity EEG activity of 3.5-7.5 Hz that occurs intermittently during early stages
of slow-wave and REM sleep.
Delta activity Regular, synchronous electrical activity of less than
4 Hz recorded from the brain; occurs during the deepest stages of slow-wave sleep.
EEG
Stages of Sleep
o Stage 1 o A transition period of drowsiness between
waking and sleeping.o Sleep spindles occur
o Stage 2 o Somewhat more deeply asleep.o Delta waves slight
o Stage 3 o Slow wave sleep beginso Delta waves reach 20%.
o Stage 4 – Delta waves reach nearly 100%.
Stage 1 similar to awake EEG, but slower low-voltage, high-frequency
EEG voltage increases and frequency decreases as one progresses from stage 1 through 2, 3, and 4
Stage 2 – characterized by K complexes – large negative waves Sleep spindles – burst of 12-14 Hz waves
Stages 3 and 4 – delta waves, large and slow Progress to stage 4 sleep and then retreat to stage 1
Sleep Cycle & EEG
Emergent stage 1 differs from initial stage 1 REMs Loss of body core muscle tone
Progress through sleep stages in 90 minute cycles More time spent in emergent stage 1 as night progresses Emergent stage 1 sleep = REM sleep
Non-REM (NREM) sleep = all other stages Stage 3 + 4 = slow-wave sleep (SWS) During REM: REMs, loss of core muscle tone, low-
amplitude/high-frequency EEG, increased cerebral and autonomic activity, muscles may twitch
Sleep Cycle & EEG
NREM Sleep
o Non-rapid eye movement sleep.o Four sleep stages1. Lightest sleep2. Mid-sleep3. Deep sleep4. Deepest sleep
o Heart and respiration slow and regular
o Little body movemento Blood pressure and brain activity
at lowest points of 24 hour period.
REM Sleep Non-REM sleep
All stages of sleep except REM sleep.
REM sleep A period of desynchronized EEG activity during sleep, at which time
dreaming, rapid eye movements, and muscular paralysis occur. 80% of awakenings from REM yield reports of story-like dreams
Slow-wave sleep Non-REM sleep, characterized by synchronized EEG activity during
deeper stages.
Basic rest-activity cycle A 90-minute cycle (in humans) of waxing and waning alertness,
controlled by a biological clock in the caudal brain stem; controls cycles of REM sleep and
slow-wave sleep.
REM Sleepo Rapid eye movement
sleepo Called “active sleep”o 20-25% of a night’s sleep
o Internally:o Intense brain activityo Brain metabolism
increaseso Brain temperature rises
rapidlyo Epinephrine release
leads to increases ino Blood pressureo Heart rateo respiration
o Externally:o Body appears calmo Large muscles become paralyzedo Eyes dart aroundo Dreaming occurs in 80%
of peopleo The brain conducts
o Consolidation of learning (all night studying doesn’t help)
o perceptual skills increase after 8-10 hours of sleepo Memory consolidation
REM Rebound
o The increased amount of REM sleep that occurs after REM deprivation
o Intensity of REM sleep increaseso Those with Sleep Deprivation
o Proceed more rapidly into REM as REM deprivation increases
o More time spent in REM when deprivation is over
o Often associated with unpleasant dreams or nightmares
o Alcohol, amphetamines, cocaine, and LSD use suppress REM sleep results in REM rebound
o Withdrawal results in REM rebounds REM rebound suggests that REM sleep
serves a special function
Purpose of REM?
Necessary for mental health Inconsistent with the effects of tricyclic
antidepressants – block REM Necessary for maintenance of normal levels of
motivation Necessary for processing of memories No clear purpose
Default Theory of REM REM serves no critical function One can’t stay continuously in non-REM sleep, so we
switch between REM and wakefulness When bodily needs exist – wake up No immediate needs – REM No REM rebound seen when lost REM periods replaced
with 15-mins awake
Variations in Sleep
o Infants and young children o have the longest sleep time
o Have the highest of REM and slow wave sleep
o Ages 6-pubertyo Most consistent sleepers and wakers
o Sleep and awake same time daily
o Adolescentso Sleep patterns are influenced by their
schedules
o Sleep longer when no schedule conflicts
o Poor sleep may contribute to poor school performance
Effects of Sleep Deprivationo Causes
o Difficulty concentratingo Attention lapseo General irritability o Decreases cognitive functioningo Impairs learning
Recuperation theories predict: Long periods of wakefulness will result in
disturbances Disturbances will get worse as deprivation
continues After deprivation, much of the missed sleep will
be regained What does the research indicate?
Studies of Sleep Deprivation in Humans
Does sleep loss affect your performance?
We tend to be poor judges of the effects of sleep deprivation on our performance
3-4 hours of deprivation in one night Increased sleepiness Disturbances displayed on
written tests of mood Perform poorly on tests of
vigilance
2-3 days of continuous deprivation Experience microsleeps,
naps of 2-3 seconds Effects on complex
cognitive function, motor performance, and physiological function are less consistent
Sleep-Deprivation Studies with Lab Animals
Carousel apparatus used to deprive rats of sleep When the experimental rat’s
EEG indicates sleep, the chamber floor moves – if the rat does not awaken, it falls into water
Yoked controls – subjected to the same floor rotations
Experimental rats typically die after several days
Postmortem studies reveal the extreme stress experienced by the experimental rats
Carousel apparatus
Theories of Sleep Function
o Restorative theory, holds that being awake produces wear and tear on the body and brain, and sleep serves the function of restoring the body and mind.
o Circadian theory of sleep is based on the premise that sleep evolved to keep humans out of harm’s way during the dark of night and possibly from becoming prey of some nocturnal predator.
Sleep Disorders - Parasomnias
o Somnambulism (sleepwalking) o occurs during partial arousal from stage 4 sleep.
o Sleep terror o happens during partial arousal from stage 4 sleep o usually begins with a piercing scream.
o Nightmares o are frightening dreams that occur during REM sleep.
o Somniloquy (Sleeptalking) o occurs during any sleep stageo is more frequent among children.
Major Sleep Disorderso Insomnia
A sleep disorder characterized by Disorders of sleep initiation and maintenanceo Difficulty falling or staying asleepo Waking too earlyo Sleep that is light, restless, or of poor quality
Symptoms can lead to distress and impairment in daytime functioning
o Hypersomnia o Disorders of excessive sleep or sleepiness
Major Sleep Disorderso Sleep apnea
Periods during sleep when breathing stops and the individual must awaken briefly in order to breathe
o 2 types1. Caused by muscle spasms or atonia2. Failure of the CNS to stimulate breathing
Most commonly seen in males, the overweight, and in the elderly
The major symptoms are excessive daytime sleepiness and extremely loud snoring, often accompanied by snorts, gasps, and choking noises
Alcohol and sedatives aggravate the condition Can lead to chronic high blood pressure, heart problems, and
even death Neuroscientists have also found that it can cause mild brain
damage The interrupted sleep experienced by individuals with this
disorder affects cognitive as well as physiological functioning
Major Sleep Disorders
o Narcolepsy o Also a form of hypersomnia
o Characterized by excessive daytime sleepiness and repeated brief uncontrollable attacks of daytime REM sleep, usually lasting 10 – 20 minutes
o An incurable sleep disorder o Cataplexy – loss of muscle tone while awakeo Sleep paralysis – paralyzed while falling asleep or upon
wakingo Hypnagogic hallucinations – dreaming while awakeo Appears to be an abnormality in the mechanisms that triggers
REMo Dreaming and loss of muscle tone while awake – suggest
REM intruding into wakefulnesso REM without atonia – able to act out dreams – possibly caused by
damage to the nucleus magnocellularis or its output
What Other Forms Can Consciousness Take?
• An altered state of consciousness • A mental state other than ordinary waking consciousness, such
as sleep, meditation, hypnosis, or a drug-induced state• occurs when some aspect of normal consciousness is modified
by mental, behavioral, or chemical means
• Hypnosis • Induced state of altered awareness, characterized by
heightened suggestibility and deep relaxation
• Meditation• Form of consciousness change induced by focusing on a
repetitive behavior, assuming certain body positions and minimizing external stimulation
• Psychoactive drug states• Chemicals that affect mental processes and behavior by their
effects on the nervous system
HypnosisA procedure through which one person,
thehypnotist, uses the power of suggestion to induce changes in a person’s:o Thoughtso FeelingsSensationso Perceptionso Behavior
Hypnotizability – Degree to which an individual is responsive to hypnotic suggestions o 80-95% of people are hypnotizable to some degreeo About 5% can reach deepest levels
Misconceptions About Hypnosiso Hypnotized people are under the complete
control of the hypnotists and will violate their moral values
o People can demonstrate superhuman strength and perform amazing feats under hypnosiso Subjects are not stronger or more powerful under
hypnosis
o Memory is more accurate under hypnosiso Pseudomemories – false memories constructed
through guidance.
o People under hypnosis will reveal embarrassing secrets
o Hypnosis is not like a truth serumo Subjects can keep secrets or lie under hypnosis
o People under hypnosis can relive an event that occurred when they were children and can function mentally as if they were that age. Careful reviews of studies on hypnotic age regression
have found no evidence to support this claim
MeditationA group of techniques that involveo focusing attention on
o an object o a wordo one’s breathing, o one’s body movements
o An effort to block out all distractions o Enhance well-beingo Achieve an altered state of consciousness.o Includes: Yoga, Zen, and transcendental meditation
Yoga A meditator typically assumes a cross-legged position known as the
lotus and gazes at a visual stimulus Zen
The individual counts breaths or concentrates on the breathing process
o Can be helpful with physical and psychological problems o Lower blood pressureo Learn how to control emotions
Physiological Mechanisms of Sleep and Waking
Types of neurotransmitter involved
1. Acetylcholine One of the most important neurotransmitters involved in arousal. Two groups of acetylcholinergic neurons located in the pons and basal
forebrain. They produce activation and cortical desynchrony when they are stimulated.
2. Norepinephrine Catecholamine agonists produce arousal and sleeplessness; effects appear to be
mediated by the locus coeruleus in the dorsal pons.
3. Serotonin (5-HT) Appears to play a role in activating behavior; almost all of the brain’s serotonergic
neurons are found in the raphe nucleus. These neurons are located in the medullary and pontine regions of the brain.
4. Histamine A neurotransmitter implicated in the control of wakefulness and arousal; a
compound synthesized from histidine, an amino acid.
Physiological Mechanisms of Sleep and Waking
Neural control of arousal
Locus coeruleus A dark color group of noradrenergic cell bodies located in the pons near the
rostral end of the floor of the fourth ventricle; involved in arousal and vigilance.
Raphe nucleus A group of nuclei located in the reticular formation of the medulla, pons, and
midbrain, situated along the midline; contains serotonergic neurons.
Tuberomammillary nucleus A nucleus in the ventral posterior hypothalamus, just rostral to the mammillary
bodies; contains histaminergic neurons involved in cortical activation and behavioral arousal.
Hypocretin A peptide also known as orexin, produced by neurons whose cell bodies are
located in the hypothalamus; their destruction causes narcolepsy.
Physiological Mechanisms of Sleep and Waking
Neural control of slow-wave sleep
Ventrolateral preoptic area (VLPA)A group of GABAergic neurons in the preoptic area whose
activity suppresses alertness and behavioral arousal and promotes sleep.
Destruction of this area has been reported to result
in total insomnia, coma, and eventual death in rats.
Physiological Mechanisms of Sleep and Waking
Neural control of REM sleep
PGO wave (pontine, geniculate, occipital):
Bursts of phasic electrical activity originating in the pons, followed by activity in the lateral geniculate nucleus and visual cortex, a characteristic of REM sleep.
Psychoactive DrugsAny substance that has powerful effects on the brain and alters:
o Consciousness
o Mood
o Perception
o Thought
Psychoactive drugs are:o Controlled substances
o approved for medical use
o Illicit drugs
o drugs that are illegal
o Over-the counter drugs
o Antihistamines
o Decongestants
o Herbal preparations
o Certain foods
o chocolate
HallucinogensHallucinogens
DepressantsDepressants
OpiatesOpiates
StimulantsStimulants
How Drugs Affect The Brain
All physical pleasure has a neurological basis:
Brought about by increase of dopamine in limbic system known as
the Nucleus Accumbens
A surge of dopamine has a
o reward and motivational effects
o produced by psychoactive drugs.
The effects of drugs cascades down involving the
brain’s entire neurotransmitter system.
How Drugs Affect The Brain
HallucinogensHallucinogens
Alter perceptions of the external environment and inner awareness (also called psychedelics)
• Mescaline• LSD• PCP• Cannabis
How Drugs Affect The Brain
OpiatesOpiatesHighly addictive; produce a sense of well-being and have strong pain-relieving properties
Heroin, Morphine, Heroin and Methadone
o Mimic the effects of the brain’s own endorphins
o Chemicals in the brain with pain relieving properties
o Produce feelings of well-being
o Useful in pain management
How Drugs Affect The Brain
DepressantsDepressants Slow down mental and physical activity by inhibiting transmission of nerve impulses in the central nervous system
o Alcoholo Barbiturateso Benzodiazepines (Tranquilizers)
oValium and Librium
o Act on GABA receptors to produce a calming, sedating effects.
o Useful in reducing a patient’s nervousness prior to undergoing a medical procedure.
How Drugs Affect The Brain
StimulantsStimulantsArouse the central nervous system, speeding up mental and physical responses
o Mimics the effects of epinephrine
o The neurotransmitter that triggers the nervous system
o Caffeine
o Nicotine
o Amphetamines
o Cocaine
o MDMA (ecstasy)
o Benefits include suppression of hunger and digestion
o Often found in “diet pills”
How Drugs Affect The Brain
Amphetamines affect the parts of the brain that control attention and concentration, as well as the nucleus accumbens. o Stimulate the release of dopamine in frontal cortex improving attention and concentration
This helps explain why these stimulants are useful in the treatment of attention problems in school children (i.e. ADHD).
Substance AbuseA continued use of a substance after several episodes in which
use of the substance has negatively affected an individual's work, education, and social relationships.
o People progress from substance “use” to “abuse” byo The physical pleasureo Genetically based differences in people’s responses to
drugso e.g. People who drink more to “feel the effect” are more
likely to become alcoholics
o Personality and social factorso e.g. Impulsiveness
o Stress related variableso e.g. Victim of child abuse or domestic violence
o Social and cultural factorso e.g. Associating with peers who abuse drugs
Drug Dependence
Commonly called “addiction”
o Physical drug dependenceo A compulsive pattern of drug use in which
o the user develops a drug tolerance o coupled with unpleasant withdrawal symptoms
when the drug is discontinued.
o Drug Toleranceo A condition in which the user becomes
o progressively less affected by the drug o must take increasingly larger doses
to maintain the same effect or high.
Drug Dependence
o Withdrawal Symptomso The physical and psychological symptoms that occur
when a regularly used drug is discontinuedo Usually the exact opposite of the effects produced by the
drugs
o Symptoms terminate when drug is taken again.
o Psychological Drug Dependenceo A craving or irresistible urge for the drug’s pleasurable
effects.o More difficult to combat than physical dependence o Drugs that may not be physically addictive may be due
to psychological dependenceo Learning processes (classical conditioning) are
important elements in development and maintenance of psychological dependence
The Behavioral Effects of Psychoactive Drugs
DETAILED DESCRIPTION
The Behavioral Effects of Psychoactive Drugs
o Stimulantso Speed up activity in the central nervous system
o Increase blood pressure, pulse rate, respiration rate, and reduce cerebral blood flow
o Suppress appetiteo Help ‘feel’ more awake and energetico Also called “uppers”o High doses make people “feel” more
o Nervouso Jitteryo Restlesso Shaky or tremblingo Interfere with sleep
Stimulants Continued
o Caffeineo Coffee, tea, cola, chocolate, and 100+ prescriptions and over-
the-counter drugso May improve visual acuity o Withdrawal for moderate to heavy use induces
o Nervousness
o Instability
o Headaches, drowsiness
o Decreased alertness
o EEG’s confirm withdrawal effects on the braino Significant increases in blood pressure and velocity of blood flow
in all four cerebral arteries
o Increase in slower brain waves causing decreased alertness and drowsiness
Stimulants Continued
o Nicotineo Increases alertnesso Suppresses appetite in some peopleo Highly addictiveo Hypnosis treatments are largely ineffectiveo Nicotine patches help 1 in 5 smokers quit
Stimulants Continued
o Amphetamineso Increase arousalo Relieve fatigueo Improve alertnesso Suppress appetiteo Give a rush of energyo Stimulate the release of dopamine in frontal cortex
improving attention and concentration o (helping with ADHD )
o Can cause confused and disorganized behaviorso Extreme fears and suspiciousness
o Delusions and hallucinations
o Aggressive and antisocial behaviors
o Manic behaviors and paranoia
Stimulants Continued
o Cocaineo Stimulant derived from coca leaveso Can be sniffed, injected, or smoked as cracko Euphoria is followed by an equally intensive crash marked by
o Depression
o Anxiety
o Agitation
o A powerful craving for more drug
o Stimulate the reward (pleasure) pathways in braino Reward pathways fail with continued use so no pleasure is felt
except when taking the drugo Main withdrawal symptoms are psychological
o Inability to feel pleasure
o Strong desire for more drug
Depressantso Alcohol
o Depresses central nervous systemo Increased drinking causes
o Slurred speecho Poor coordinationo Staggeringo Impaired depth perceptiono Men tend to become aggressive and sexually aroused yet
less able to perform sexuallyo Decreases ability to form new memorieso Drinker’s expectations of alcohol effects also contribute to
alcohol’s effect
Depressantso Barbiturates
o Depress central nervous systemo Act as sedative or sleeping pill dependent on amount takeno Abusers become
o Drowsy and confused
o Thinking and judgment suffer
o Coordination and reflexes are affected
o Can kill if taken in overdose (as little as three times regular dose)
o When taken with alcohol are potentially fatal
o Minor Tranquilizerso Benzodiazepines (valium, Librium, dalmane, xanax)o Abuse is associated with
o temporary and permanent impairment of memory and other cognitive functions
Hallucinogens (psychedelics)
o Drugs that alter and distort perceptions of time and space, alter mood, produce feelings of unreality, and cause hallucinations.
o Marijuana (THC tetrahydrocannabinol)o Produces a higho Remains in the body for days or even weekso Impairs attention and coordinationo Slows reaction time after intoxication feeling has passedo Interferes with concentration, logical thinking, and ability to
form new memorieso Produces fragmentation in thoughto Confusion in remembering recent occurrenceso Chronic use associated with loss of motivation, general
apathy, and decline in school/work performanceo Medical benefits include treatment of glaucoma, controlling
nausea in cancer patients, and improving appetite and controlling weight loss in AIDS patients
Hallucinogens (psychedelics)o LSD (Llysergic Acid Diethylamide)
o Often referred to as “acid”o A “trip” lasts 10-12 hours and produces
o extreme perceptual and emotional changes
o Visual hallucinations
o Feelings of panic
o Bad “trips” are associated witho Accidents, death, or suicide
o Flashbacks or ‘hallucinogen persisting disorder’
o Designer Drugso Mimic pleasurable effects of other drugso STP and Ecstasyo Derived from amphetamines o Have hallucinogenic and stimulant effect