States of Consciousness

States of Consciousness

SLEEP

ConsciousnessAwareness of yourself and

your environment

• Being awake and aware– Are automatic behaviors conscious

• Freud: what you are actively thinking about• Which of the following is consciousness– Sleeping -- Talking to your friend– Coma -- Having Fainted

Consciousness versus Automatic• What we are not aware of typically falls

out of our definition of consciousness• Consciousness: when brain activity

crosses a threshold of intensity– Chord=conscious, notes=unconscious

• Consciousness lags behind brain activity.• Conscious processing is serial

States of Consciousness

Biological Rhythms• Biological Rhythms are

physiological/biological patterns• Types– Circadian: once/day• Examples: sleep-wake cycle, others?

–Ultradian: >once/day• Examples: sleep cycles, others?

– Infradian: <once/day• Examples?

Sleep Rhythms• Circadian• Arousal peaks during the day, dips early

after, and then drops before we go to bed

• As we age we move from night owl to early birds– This progresses as we age– Starts around age 20 (bit earlier for women)

• Light is a key determinate in our sleep rhythms

Hormones and Sleep• Light activates light-sensitive retinal

proteinstriggers signals in the brain’s suprachiasmatic nucleus

• The SUPER NUCLEUUUUUS causes the pineal gland to increase or decrease melatonin

• Brain accumulates adenosine over the day and declines at night– Adenosine makes us sleepy

• Artificial light delays sleep and shifts our cycle back

How We Fall Sleep• Hypothalamus controls body’s

rhythm–Monitors light: when dark sends signals

to get into sleep mode• Hormones (chemical messengers)–Melatonin: correlated with

hypothalamus’s regulated schedules and light v. dark, helps signal us to sleep.

–Used as a therapy for insomnia

Why We Sleep• Preserve– Evolutionarily advantageous to sleep

when we can’t see– Protect us from predators– Animals that don’t need to hide and need

to graze sleep less• Restore/Repair– Rebuild tissues and neurons– Grow– Consolidate memories

Sleep Debt

• How much sleep do we need?– Adolescents: 8ish hours– Babies: 13-16 hrs!– Old people: 6ish hours!

• Most adults will ideally sleep 9 hrs• If we don’t get itsleep debt

Effects of Sleep Debt• Decreases immune system functioning• Increase cortisol: weight, memory, learning• Accidents• Accidents increase after spring forward and decrease after

fall back• Decreased productivity and performance• Increased likelihood for hypertension,

irritability, lower cancer-fighting immune• Sleep affects people’s moods more than money!• Sleep is closely correlated with personal life

satisfaction

Can we pay back sleep debt?• Bodies do keep track of sleep debt (2 weeks)• There is a difference between short term

and long term sleep debt• One late night can be partially paid back

with a late morning– Improvement only lasts for six hours!– Merely masks sleep debt

• Long term accumulation can cause sudden sleepiness

• Becomes a physiological habit

Sleep Stages• Occurs in a 90 minute ultradian cycle• Each cycle has two types of sleep– Types: REM (rapid eye movement) and NREM

(non-rapid eye movement)• Five stages (1 stage of REM, 4 NREM)• To monitor stages we use EEG

(electroencephalograph)– Electrodes measure brain waves– Compare electrical activity in different

regions of the brain– Usually five regions are monitored

Sleep Waves

Wave Summaries

• Alpha Waves– 7.5-14 Hz– Awake,

relaxed– Meditation

• Beta Waves– 14-40 Hz– Normal

awakened alertness

– Higher stress, but pretty common

• Theta Waves– 4-7.5 Hz– Sleep

(including REM)

• Delta Waves– .5-4 Hz– Deep sleep– Regenerativ

e sleep• Gamma

Waves– >40 Hz– Very new!– Short bursts

of insight/advanced processing

Stages One• Stage One– Transition between awake and asleep– Slowed breathing, irregular brain

waves– Individual might not even claimed to

have been asleep, they were “just resting their eyes”

– Irregular Waves– Characteristics: hallucinations,

hypnagogic sensations (falling, floating)

Stages Two• Stage Two– Characterized activity• Burst of brain activity: spindles• K-Complex, largest event in normal EEG

activity– Clearly asleep, but can be woken– Sleep talking can occur

Stage Three and Four• Stage Three– Deep Sleep– Presence of delta waves (high amplitude, low

frequency)• 5-50% at stage three• Entirely at stage four

– Hard to wake up– End of stage four is when you see sleep

walking and bed wetting

Stage Five (REM Sleep)

• REM=Rapid Eye Movement• Brain waves appear almost as if you were

awake– Paradoxical Sleep: mind awake, but can’t be aroused

• Eyes move, pulse and breathing are faster, blood flow increases

• Eyes dart under closed lids every 30 seconds• Temporary paralysis through the brainstem• Dreams occur• Sexual arousal occurs (and can last after REM)– Nightmares are an exception

Your Body Asleep• We process information outside of

conscious awareness– Sound of a baby versus a train– Falling out of bed

• Motor cortex is active– Brainstem blocks messages from the

motor cortex– Fundamental paralyzed minus slight

muscle twitches

Dreams• Occurs during REM sleep• Often emotional and storylike seeming

to include almost hallucinations• Visual and auditory areas are more

active in REM and inactive in other stages

• Eye movement does not match dream content or watching dream

• On average people spend 100 minutes in REM (20-25%)– Everyone dreams!

Lucid Dreams• Dreams where you are aware you are

dreaming• Having some control over role in dream• More beta waves and parietal lobe

activity

Why We Dream• Reason 1: Information Processing– Shift and sort through the day’s

experiences– Delta sleep stabilizes memories and

REM sleep helps cement them into learning• Correlation between grades and sleep

–More stress, more sleep–What about dreams about nothing we

have experienced?

Why We Dream• Reason 2: Physiological Function– REM activity (aka dreams) provides brain

stimulation to support growth (remember your neurons!)

– Growth hormone is secreted during delta sleep

– Babies need much more REM sleep than other individuals

– Problem: what about meaningful dreams?

Why We Dream• Reason 3:

Activation-Synthesis–Minds way of making

sense out of random neural firings

– Problem: why does it make the stories that it does? Where does the content come from?

Why We Dream• Reason Four: Freud’s

Wish Fulfillment– The Interpretation of

Dreams–Manifest Content

• Story line of dreams• Symbolic

– Latent Content• What the symbols mean• Usually sexual

– Problems• Lack scientific evidence

Why We Dream• Reason Five: Cognitive Development– Part of intellectual/brain development– Dreams move from slideshows in childhood

to movie where dreamer is an actor– Dreams use our concepts, knowledge, and

skillsGood chart on page 289

Sleep Disorders

1. Insomnia: Can’t stay or fall asleep2. Narcolepsy: Sudden, overwhelming sleeping3. Sleep Apnea: Snoring to the extent one stops

breathing4. Night Terrors5. Somnambulism: Sleep walking6. Enuresis: Bed wetting

1: Insomnia• Consistent problems staying or falling asleep• People tend to overestimate how long it takes them

to fall asleep• Solutions

– Sleeping pills/alcohol: aggravate the problem!– Relax before bedtime– Establish routine– Use dimmer light– Avoid caffeine and rich food (glass of milk can be okay

because it provides serotonin)– Build a consistent schedule and avoid naps– Exercise regularly but not in the late evening– Aim for less sleep

2: Narcolepsy• Periodic, overwhelming sleepiness for

(usually) < 3 minutes• Can collapse into REM sleep• Affects about 1 in 2000 people• There seems to be a correlation with

birth month and disorder• Genetic– Absence of the hypothalamic neural center

that produces hypocretin

3: Sleep Apnea

• Temporary cessations of breathing during sleep with momentary awakenings

• Affects mostly overweight men

• Symptoms: tired and irritable during the day (spouse often has similar symptoms)

• Affects about 1 in 20• Solutions– CPAP Machine (mask with air

pump to help keep airways open)

4: Night Terrors• High arousal and terror mid-stage four

sleep• Sufferer is usually a child and will have no

recollection of the event• Usually outgrown• As we spend less time in stage four we see less

of this, that’s why it is outgrown

5: Somnambulism• Sleep walking• Stage four disorder– As we spend less time in stage four we see

less of this, that’s why it is outgrown• Runs in families (much like sleep

talking)

HYPNOSIS

DRUGS