sleep

Consciousness

Awareness of internal or external stimuli

Normal waking consciousness

Being awake and aware of internal and external stimuli

Altered states of consciousness

Lack of awareness of internal and external stimuli

Types of altered states of consciousness

Naturally occurring and induced

Naturally occurring altered state of consciousness

Normal part of everyday life, does not require aids (sleep)

Induced altered state of consciousness

Intentionally brought on by some kind of aid (alcohol)

Sleep

Typically naturally occurring altered state of consciousness that occurs regularly

How is sleep characterised

By partial of total suspension of conscious awareness

Sleep as a psychological construct

Concepts, descriptions, or explanatory models that are constructed to describe specific psychological activity or a pattern of associated activities or processes

NREM

Non rapid eye movement sleep

REM

Rapid eye movement sleep

Sleep cycles

Sleep occurs in cycles that last approx. 90-120 mins

What are the components of a sleep cycle

NREM 1, NREM 2, NREM 3, REM

Duration of sleep

8 hours, 4-5 cycles

NREM stage 1

• Falling/light sleep

• Decreased heart rate, breathing rate, body temp, and muscle tension

• Slow rolling eye movements

• Involuntary muscle twitches (hyping jerks)

• Low arousal threshold (easy to wake)

• Slow down of brain waves

• 4-5% total sleep time

NREM stage 2

• Moderate sleep

• Decreased heart rate, breathing rate, body temp, and muscle tension

• No eye movement

• Middle arousal threshold (still easy to wake)

• Further slow down of brain waves

• 10-25 min duration in first sleep cycle, duration increase throughout the night

NREM stage 3

• Deep sleep

• Lowest level of heart rate and breathing rate, muscles are completely relaxed

• No eye movement

• High arousal threshold (hard to wake)

• Largest and slowest brain waves

• Longest in early cycles, duration decreases throughout the night

REM characteristics

• Rapid eye movements

• 20-25% of total sleep time

• Periods of rem lengthen and become closer together throughout the night

• Brain is very active

• Heart rate is fast and irregular, blood pressure rises, breathing is shallow and fast, and body is paralysed

Sleep hypnotism characteristics

• NREM and REM stages are sequential

• Each cycle is 0-120 mins

• Deeper stages of NREM disappear gradually

• Duration in NREM decreases while duration in REM increases

• Each cycle is made of a periods of NREM and REM

Subjective data

Based on personal opinion, interpretation, POV, or judgement

Objective data

Observable, measurable, and verifiable

Quantitative data

Numerical info on the quantity of what is being studied

Qualitative data

Non numerical info on the qualities of a participants experience of whats being studied

EEG

• Detects, amplifies, and records electrical activity of the brain

• Objective method

Brain waves

Spontaneous, rhythmic electrical impulses that come from diff brain areas

Beta waves

• Alertness, concentration, thinking

• High frequency

• Low amplitude

Alpha waves

• Meditation, creativity, relaxation

• High frequency

• Low amplitude

Theta waves

• Visualisation, trance, dreaming

• Med frequency

• Med-high amplitude

Delta waves

• Deep sleep, transcendence, restoration

• Low frequency

• High amplitude

EMG

• Detects, amplifies, and records activity of muscles

• Higher muscle activity and tone = more alert

• Objective method

EOG

• Detect, amplifies, and records electrical activity in eye muscles that control eye movements

• Objective method

Sleep diaries

• Self recorded and reported log of sleep and waking time over a period of time

• Subjective method

Video monitoring

• Observing sleep through cameras to monitor and recording externally observable physiological responses in real time over a prolonged period

• Subjective method

Biological rhythms

Naturally occurring cycle of physiological, psychological, or behavioural changes

Biological clock

Innate timing mechanism that regulates the cycle of a biological rhythm

Ultradian rhythm

Physiological, psychological, or behavioural changed that occur as part of a cycle shorter than 24 hrs (heartbeat)

Circadian rhythm

Physiological, psychological and behavioural changes that occur as part of cycles with a duration of approx. 24 hrs

Endogenous

Originates within an organism

Exogenous

Originates outside an organism

Human sleep-wake cycle

• 24 hr cycle of being asleep and awake

• Responsible for body clock

• Naturally occurring

• Self regulated by suprachiasmatic nucleus

• Endogenous

Suprachiasmatic nucleus

• Regulates timing and activity of sleep-wake cycle

• Adjusts sleep-wake cycle in response to light and darkness

• Keeps cycle in sync with the 24hr day and night cycle

• Receives info from eyes and signals to pineal gland to modify melatonin release

Melatonin

• Released by the pineal gland

• Influences alertness and drowsiness

• High melatonin = greater drowsiness, less alertness

Impact of light

1. Light enters eyes, eyes send info to suprachiasmatic nucleus

2. Suprachiasmatic nucleus regulates release of melatonin

3. Increase in melatonin results in sleepiness

Neonatal period

1-15 days

Infancy

3-24 months

Childhood

2-14 years

Adolescence

14-18 years

Young adulthood

18-30 years

Middle adulthood

30-75 years

Old age

75+ years

Neonatal period characteristics

• 16hr sleep

• 50% NREM

• 50% REM

Infancy characteristics

• 13.5 hr sleep

• 65% NREM

• 35% REM

Childhood characteristics

• 11 hr sleep

• 80% NREM

• 20% REM

Adolescence characteristics

• 9 hr sleep

• 80% NREM

• 20% REM

• 1-2 hr delay in sleep onset

Young adulthood characteristics

• 7.75 hr sleep

• 80% NREM

• 20% REM

Middle adulthood characteristics

• 7-8 hr sleep

• 80% NREM

• 20% REM

Old age characteristics

• 6 hr sleep

• 80% NREM

• 20% REM

• Advanced sleep onset

Sleep duration…

…decreases as individuals age

NREM/REM proportion

• REM decreses significantly in first 2 yrs of life

• NREM decreases steadily

Awakenings during sleep…

…increase as individuals age

Sleep onset

Different ages result in differences in sleep onset time and duration

Why do characteristics of sleep alter as individuals age?

• Sleep changes due to physical and cognitive needs

• REM is important for brain and cognitive development

• NREM is important for physiological rest and development

Sleep disturbance

Any sleep related issue that interupts an individuals normal sleep-wake cycle

Sleep disorder

A sleep disturbance that is persistent and regularly disrupts sleep, causing distress in important areas of everyday life

Primary sleep disorder

Main cause of the sleep disturbance

Secondary sleep disorder

The result of another condition or use of a substance

Sleep deprivation

A state caused by inadequate quality or quantity of sleep

Partial sleep deprivation

Having sleep quality or quantity of sleep than what is normally required

Total sleep deprivation

No sleep at all over a 24 hr period

Partial sleep deprivation impact on affective functioning

• Anxiety

• Amplified emotional responses

• Mood swings

• Increased irritability

• Easily annoyed

Partial sleep deprivation impact on behavioural functioning

• Microsleeps

• Excessive sleepiness

• Sleep inertia

• Slower reaction time

• Dizziness

• Slurred speech

• Shaking hands

Sleep inertia

Confusion when woken up

Partial sleep deprivation impact on cognitive functioning

• Confusion

• Inability to think clearly

• Thoughts that do not make sense

• Difficulty retrieving or forming memories

Blood alcohol concentration

Measure of how much alcohol is in an individuals bloodstream

Alcohol

Depressant drug that slows the nervous system, decreases alertness, reflexes, and concentration

17 hrs of sleep deprivation is equivalent to a BAC of…

0.05%

24 hrs of sleep deprivation is equivalent to a BAC of…

0.10%

Alcohol impact on affective functioning

• Feelings of happiness, excitement, anger, or sadness

• Long term effects lead to dulling effects and depression

• Difficulty judging emotions

• Amplified emotional responses

Alcohol impact on cognitive functioning

• Slower mental processes

• Decreased ability to reason and problem solve

• Reduced ability to make decisions quickly and effectively

• Cognitive distortions

Circadian rhythm sleep disorders

Sleep disorders that are primarily due to a mismatch between a persons sleep-wake pattern and their desired pattern

Circadian rhythm sleep disorders may be cause by…

1. Mismatch between sleep-wake cycle and day-night cycle of physical environment

2. Mismatch between sleep-wake cycle and the sleep-wake schedule required by school or work

Delayed sleep phase syndrome

Major sleep ep occurs later than usual, sleep-wake cycle is delayed

Advanced sleep phase disorder

Major sleep ep occurs earlier than usual, sleep-wake cycle is advanced

Shift work

Occupation leads individuals to work at unusual times, resulting in them sleeping at unusual times

Bright light therapy

Used to adjust a persons sleep-wake cycle to a desired schedule through exposure to high intensity light sources

Bright light therapy factors

1. Must be at an appropriate time

2. Must be the appropriate amount of light

3. Must be safe

How can bright light therapy aid DSPS

Light exposure in the morning acts as external cue to SCN to promote wakefulness by signalling the release cortisol. This helps SCN to send signals for melatonin release at an earlier time.

How can bright light therapy aid ASPS

Light exposure in the evening acts as external cue to SCN to promote wakefulness by signalling the release cortisol. This helps SCN to send signals for melatonin release at a later time.

How can bright light therapy aid in shift work

Light exposure before the beginningof a shift acts as external cue to SCN to promote wakefulness by signalling the release cortisol. This helps SCN to send signals for melatonin release at a later time when the person is not required to work.

Sleep hygiene

The habits that promote an individuals sleep patterns. Good sleep hygiene improves sleep quality and quantity.

Zeitgebers

External cues from the environment that influence the circadian rhythm. Regulates sleep-wake cycle and promotes sleepiness and wakefulness

Zeitgebers - blue light

Light that is emitted naturally and artificially. Promotes wakefulness by signalling to the suprachiasmatic nucleus to cease melatonin production

Zeitgebers - daylight

Light individuals are exposed to during the day. Promotes wakefulness by signalling to the suprachiasmatic nucleus to cease melatonin production

Zeitgebers - temperature

The degree of external heat in the environment. Extreme temps are not good for quality or quantity of sleep

Zeitgebers - eating and drinking

What individuals consume influences quality and quantity of sleep. Eating too close tobsleep time negatively impacts sleep as the digestive system is stimulated. Going to sleep too hungry or full can negatively impact sleep quality and quantity

Zeitgebers - eating and drinking - caffeine

• Increases activity of nervous system

• Blocks sleep promoting neurotransmitters

• Promotes wakefulness

Zeitgebers - eating and drinking - high sugar and fat foods

Negatively impacts sleep quality and quantity