AOS 3 - Sleep

Sleep

what is consciousness

the level of awareness an individual has of their thoughts, feelings, perceptions and existence

what is normal waking consciousness

is where an individual is awake and aware

what is altered state of consciousness

any state on consciousness that is distinctly different from NWC

Sleep

is a regular and naturally occurring altered state of consciousness

sleep episode

the full duration of time spent asleep

sleep cycle

an approximately 90-minute-period that repeats during a sleep episode

stage 1 NREM sleep

light sleep, some people experience floating or falling or a sudden jerk, lose awareness of themselves and their surrounding but still aware of faint sounds

stage 2 NREM sleep

relatively light sleep, most time spent during sleep, officially considered asleep in this stage, observable through brain waves

stage 3 NREM sleep

deep stage of sleep, difficult to wake, sleeper is woken will feel drowsy and disoriented, sleep walking and sleep talking may occur

3 objective measurements of sleep

EEG, EOG and EMG

EEG

detects, amplifies and records the electrical activity of the brain using electrodes attached to the scalp

what levels would the electrical activity be in REM and NREM using EEG

higher levels of electrical activity in REM and lowers levels in NREM

what are brain waves amplitudes and frequencies in REM sleep

amp - low

freq - high

what are brain waves amplitudes and frequencies in NREM sleep

amp - high

freq - low

EMG

detects, amplifies and records the electrical activity of facial muscles using electrodes usually attached to the jaw

muscular activity that indicates NWC

active and tension

muscular activity that indicates ASC

relaxed

what levels would the electrical activity be in REM and NREM using EMG

show electrical activity slowing during NREM no electrical activity of the muscles during REM

EOG

detects, amplifies and records the electrical activity of the eye muscles using electrodes attached to the face around the eyes

muscular movements around eye activity that indicates NWC

active and tension

muscular movements around eye activity that indicates ASC

relaxed

what levels would the electrical activity be in REM and NREM using EOG

high during REM and low during NREM

Biological rhythms

repeated biological processes that are regulated by internal mechanisms

Circadian Rhythms

biological and behavioural changes that occur as part of a cycle that lasts around 24 hours

sleep wake cycles

a 24-hour cycle that is made up of time spent sleeping and time spent awake and alert, it is determined by an internal body clock

where is an internal body clock located

hypothalamus

what does this internal body clock regulate

our level of arousal, metabolism, body temperature and hormone secretions

circadian rhythms is finely tuned by…

environmental signals or cues

the main environmental cue is…

light

ultradian rhythms

biological and behavioural changes that occur in a cycle that lasts less than 24 hours

2 hormones that regulate the sleep-wake cycle

melatonin and cortisol

melatonin

a hormone released by the pineal gland, low levels in morning, high levels at night

melatonin is controlled by…

pineal gland

cortisol

a hormone responsible for increasing alertness and maintaining heightened arousal

cortisol is controlled by…

adernal cortex

the steps of the process of the SCN regulating the sleep-wake cycle at night-time

light signals are detected by retina and sent to SCN within the hypothalamus, then uses information to regulate melatonin release into the body well the adrenal cortex regulates cortisol, if levels of light are high melatonin is inhibited and cortisol is secreted making person feels awake and if levels of light are low melatonin is secreted and cortisol is inhibited making person feels sleepy.

Babies sleep 0-1

amount - 16 hours, sleep onset - multiple times through day, % - 50% REM and 50% NREM

infant sleep 1-2

amount - 12-13 hours, sleep onset - matches outside environmental light cues, % - 35% REM and 65% NREM

children sleep 3-11

amount - 11-12 hours, sleep onset - slightly later in evening, % - 20% REM and 80% NREM

adolescents sleep 12-19

amount - 9-10, sleep onset - much later in evening, % - 20% REM and 80% NREM

Adult sleep 20 - 65

amount - 8 hours, sleep onset - slightly later in evening, % - 20% REM and 80% NREM

elderly sleep 65+

amount - 6-7, sleep onset - early in evening also waking up earlier, % - 20% REM and 80% NREM

what influence adolescence sleep patterns

environmental factors such as school making wake up earlier and social commitments at nighttime

3 types of effects of sleep deprivation

affective, behavioural and cognitive

affective effects of sleep deprivation

the changes in emotions and emotional responses that arise from sleep deprivation

affective effects of sleep deprivation examples

irritability, reduced empathy, increase mood swings, aggression, reduced ability to cope with stress and impaired ability to appropriately respond to situations

behavioural effects of sleep deprivation

the changes in actions and the ability to control them that arise from sleep deprivation

behavioural sleep of sleep deprivation examples

lack of energy, excessive sleepiness during day, increased likelihood of engaging in risk taking behaviours slowed reaction time, reduced efficiency

cognitive effects of sleep deprivation

the changes in mental processes that arise from sleep deprivation

cognitive effects of sleep deprivation examples

reduced concentration, impaired decision-making processes and problem-solving abilities, irrational or illogical thinking, rescued retention of information

similar affective effects of high BAC and sleep deprivation

emotional instability, heightened irritability, mood swings and reduced emotional regulation

similar cognitive affects of high BAC and sleep deprivation

impaired concentration, decision making and memory and slower reaction time

sleep disorders

disturbances to typical sleeping and waking patterns

circadian rhythm sleep disorders

sleep disorders that interfere with the typical regulation of the circadian rhythm of sleep, leading to a change in the sleep-wake cycle

causes of circadian rhythm sleep disorders

by a disruption to the typical sleep-wake cycle, this can be due to a biological issue or lifestyle changes

3 types of circadian rhythm sleep disorders

delayed sleep phase syndrome, advanced sleep phase disorder and shift work

delayed sleep phase syndrome

sleep disorder in which sleep and waking occurs later than usual

Why does delayed sleep phase syndrome usually occur in adolescence?

Puberty triggers a natural biological shift in the body

shift work

an occupation that involves working at unusual hours or rotating shifts

bright light therapy

a method used to adjust a persons circadian rhythm through exposure to a high-intensity light source

delayed sleep phase syndrome treatment with bright light therapy

Light exposure would take place in the early morning hours to gradually shift sleepiness to an earlier time at the other end of the day

advanced sleep phase disorder treatment with bright light therapy

Light exposure would occur in the evenings to enable individuals to fall asleep later

shift work treatment with bright light therapy

Light exposure in the evening, combined with periods of darkness during the day, can help people who work at night

sleep hygiene

the practices and habits that promote an individual’s sleep patterns

mental wellbeing

an individual’s psychological state, involving their ability to think, process information, and regulate emotions

how are mental wellbeing and sleep related

when you have poor mental wellbeing it can contribute to poor sleep and vice versa

zeitgebers

external cues from the environment that influence circadian rhythm

3 main types of zeitgebers

light, temperature and eating and drinking patterns

blue light and the 2 types

a type of light that can be emitted both naturally and artificially, daylight and artificial blue light

blue light in relation to being a zeitgeber

relates by signalling the SCN to inhibit melatonin production and make the person feel alert and awake

temperature in relation to zeitgebers

the degree of external heat in the environment that can influence the quality and quantity of sleep

Eating and drinking patterns in relation to zeitgebers

what, when, and how much food and drink is consumed by an individual

why is int hard to fall asleep when eating food close to sleep time?

stimulation of the digestive system

what foods and drinks impact sleep

caffeine, alcohol, spicy foods and high-sugar and high-fat foods