2 True or False?T/F We act out our forbidden fantasies in our dreams. T/F Insomnia can be causes by trying too hard to fall asleep. T/F It is dangerous to awaken a sleepwalker. T/F You can be hypnotized against your will. T/F You can teach a rat to raise or lower its heart rate.
3 Biological Rhythms and Mental States Consciousness:Awareness of oneself and the environment.Biological Rhythm:A periodic, more or less regular fluctuation in a biological system.Altered states of consciousness: Sleep, daydreaming, dreaming, hypnosis, meditation, intoxication.
4 Biological Rhythms and Mental States Circadian rhythm:A biological rhythm with a period of about 24 hours (Exists in all living things).Regulated by external forces-Air pressure, temperature (hibernation), rotation of the earth, presence or lack of sun light, even the moon.Suprachiasmatic Nucleus:Located inside the hypothalamus.Regulates our circadian rhythms.Responds to changes in light.Melatonin:Hormone that works in tandem with the SCN.High levels are diagnostic of being tired.Low levels are diagnostic of being alert.Melatonin levels impacted by quantity of light.Zeitgeber:Time-Giver.For humans it is the sun.
5 Biological Rhythms and Mental States The daily rhythms of the body:MetabolismStomach acidityAlertnessBody temperatureBlood pressureLevel of most hormones
6 Biological Rhythms and Mental States The body runs on a 25-hour day, thus biological clock must be reset daily (light is one way).Light resets the biological clock by inhibiting the production of melatonin (involved in the onset of sleep).
7 Biological Rhythms and Mental States Types of Circadian rhythms:Diurnal (Light-onset)Nocturnal (Light-offset)Crepuscular (Dusk/Dawn Onset)_____________________________________________________________Internal desynchronization:State in which biological rhythms are not in phase with one another.Jet-lagGraveyard ShiftSeasonal Affective Disorder: (SAD)Person experiences depression during the winter.Use light therapy.Decrease melatonin levels you will feel better.
8 Biological Rhythms and Mental States Body temperature is related to one’s level of alertness and sleep/wake cycle.An increase in body temperature = greater alertness.A decrease in body temperature = reduced alertness & motivation.
9 SleepWhy do we sleep?If our system is built to keep the organism alive and safe then why do we all spend time each day in a completely vulnerable state?Fun facts:If you live 75 years you will have spent 25 years of your life sleeping.You dream in color.Not all animals have dual-hemispheric sleeping-Dolphins have unihemispheric sleeping.Ducks can switch between dual and selective hemispheric sleeping.Your sleep cycle is regulated by your body temperature.Not by the time it says on your clock.You dream less the older you get.Longest a person has gone in total sleep deprivation has been 10 ½ days.
11 Sleep Two main theories: I. Restorative Process- Helps the animal recover from wakeful activities.Essential for maintaining proper chemical levels in the body.In humans sleep is regulated by three elements:Circadian ClockAdenosine levels increase each hour you are awake.Melatonin levels increase as the day progresses.Causes a gradual decrease in body temperature in diurnal animals.HomeostasisIndividuals ideal makeup.Willful Behavior (Motor Cortex)II. Adaptive Process-Developed because of a need of animals to protect themselves.Survival, protection of offspring, food gathering, and resource management all require energy that must be conserved.
12 SleepSleeping StagesDefined by EEG recordings and consists of five stages which can include alpha, beta, delta, and theta waves.Divided into two broad stages:Non-REM SleepStage 1 (transitional)Stage 2Stage 3 (transitional)Stage 4REM SleepStage 5
13 Sleeping StagesI. Non-REM Sleep: (Accounts for 75-80% of total sleep time)Stage 1: (TRANSITIONAL)Near disappearance of alpha waves and presentation of theta wavesSudden twitches and jerks will begin (somnolence).Subject looses muscle tone and conscious awareness of the external environment.Gateway state between wake and sleepStage 2: (45-55% of total sleep time)Onset of Sleep Spindles (12-16 Hz) and K-ComplexesConscious awareness of the external environment disappears.Stage 3: (TRANSITIONAL)Delta waves (.5-4 Hz)Considered part of Slow-wave SleepOccupies 3-8% of total sleep timeStage 4: (10-15% of total sleep time)True Delta SleepPredominates the first third of the nightDeepest stage of sleepClinical AnesthesiaNight Terrors, Bed Wetting, Sleep Walking
14 Sleeping Stages II. REM Sleep (Accounts for 20% of total sleep time) Rapid Eye Movement:Lots of activity throughout the CNS and PNS.Dreaming:Dreams can occur at any other stage as well (Hypnogogia).Predominant in the final third of a sleep period.Timing linked to body temperature (Fever).Alpha and Beta waves present.List of the five most common dreams: (Wieten, 1992)83% Falling77% Being attacked or pursued71% Trying repeatedly to do something71% Working, studying, or practicing something66% Sexual experiencesWhat function does dreaming serve?Can you analyze a dream?
18 DreamsHobson & McCarley: Dreams are generated by random bursts of nerve-cell activity.Crick & Mitchison: Dreams are a way of freeing the mind of irrelevant, repetitious thoughts.
19 Dyssomnias Defined: Disturbance in normal rhythm or pattern of sleep. Cognitive functioning declines rapidly without daily sleep.Eventually you will hallucinate and show signs typical of schizophrenia.
20 Dyssomnias Sleep Apnea: Breathing briefly stops during sleep. Caused by an obstruction in the breathing process.The obstruction causes carbon dioxide to build up.Person may choke, gasp, or momentarily awaken.Treatment-Forced air maskFor infants under one year this is lethal-They are too young for their brain to detect carbon dioxide levels in the body.Coca-Cola during first year to keep them alive.NarcolepsyInvolves sudden attacks of sleepiness.Involves boring, tedious, and repetitive tasks.
21 Dyssomnias Cataplexy: Collapsing and passing out due to increased anxiety levels.Caused by excitable and sensitive autonomic nervous system.(Myotonic goats-chloride imbalance)Pavor Nocturnus: “Night Terrors”Most common in children going through the earlystages of puberty.The individual will not remember the episode.This does not typically happen in adults.Caused by massive brain changes.
22 Dyssomnias Somnambulism: Sleepwalking Typically happens in children. MaturationAlmost never happens in adults.StressHypnagogic Hallucinations:Waking up at the end of a REM cycle.Sometimes in stage 1.Sleep Paralysis-You are completely paralyzed.Can occur in REM sleep.Muscle rigidity, visual and auditory hallucinations.Everyone has them.
23 Dyssomnias Nocturnal Emission: Spontaneously climaxing during REM sleep.Dream content does not have to be sexual.Typically during puberty.Enuresis:Urinating in bed.Encopresis:Defecating in bed.
24 DyssomniasInsomnia: Difficulty falling asleep or remaining asleep.
25 HypnosisHypnosis:Procedure in which the practitioner suggests changes in the sensations, perceptions, thoughts, feelings, or behavior of the subject.