Unit 4 AOS 1 - Sleep Flashcards
What is consciousness?
Our awareness of internal and external environments at any given time. Consciousness is personal, selective, continuous and changing.
What is the psychological construct?
Phenomena that are believed to exist but cannot be directly measured (e.g. Consciousness).
What is NWC?
Normal waking consciousness - awareness of thoughts, feelings and behaviour, including internal and external events.
What is ASC?
Altered state of consciousness - Any state that is characteristically different from NWC in terms of awareness, thoughts, feelings and behaviours. These can occur naturally or be induced.
What is the consciousness continuum?
Individuals are on a fluctuating scale from being least aware to most aware.
What is sleep?
Sleep is a psychological construct. This is because the subjective experience of sleep cannot be overtly measured, yet we still have a general understanding of what sleep is and that it exists.
Sleep is a regular and naturally occurring ASC that involves a loss of awareness and disengagement with internal and external stimuli.
What are the characteristics of sleep?
A reduced ability to control behaviour.
A reduction in the control one has over thoughts.
Less accurate understanding of the passage of time.
Perceptual and cognitive distortions.
What is REM sleep?
Rapid-eye movement sleep is a type of sleep characterised by;
Rapid eye movement.
High brain activity / Low body activity.
Levels of paralysis.
Light stage sleep which the sleeper can be easily woken from.
Vivid dreaming.
Time spent in REM sleep rises as the sleep episode progresses.
What is NREM sleep?
Non-rapid-eye movement sleep is a type of sleep characterised by;
Having 3 stages.
Less brain activity.
Lack of dreaming.
Lack of dream recollection.
Ability for skeletal movement to occur.
Time spent in NREM sleep decreases as the sleep episode progresses.
Define sleep episode.
The full duration of time spent asleep, contains multiple sleep cycles.
Define sleep cycle.
A cycle of NREM and REM sleep that lasts around 90 minutes. This is a type of ultradian cycle.
What are the characteristics of NREM stage 1?
Light sleep.
Hypnagogic state - hypnic jerks.
Easily woken from.
Faint sounds can be heard but a loss of awareness of surroundings occurs.
What are the characteristics of NREM stage 2?
First experience of being truly asleep.
Relatively light sleep.
Most time spent asleep is NREM 2.
What are the characteristics of NREM stage 3?
This is deep sleep.
Difficult to wake from.
Most likely to experience sleepwalking/talking.
What is a hypnogram?
A hypnogram graphs a person’s sleep episode based on their brainwaves.
Describe what an average adult hypnogram looks like.
Sleep cycle one - The individual will transition from wakefulness into NREM 1, followed by NREM 2, and then a period of NREM 3. This would be followed by an incredibly short period of REM sleep.
The following cycles would continue to look fairly similar (excluding NREM 1, which would likely not be returned to), however, over each cycle, the period of time spent in NREM, particularly NREM 3, would become shorter, while the period of time in REM would become longer.
The final sleep cycle would typically end with a long chunk of REM sleep, potentially up to an hour long.
Adults typically sleep for 7-8 hours, spending 80% of sleep in NREM and 20% in REM.
Describe sleep in newborns.
Newborns spend 14-16 hours asleep. 50% of this is REM, and 50% is NREM.
REM sleep replenishes the brain and consolidates memories. Since a baby is undergoing a lot of neurological changes, they spend more time in REM sleep than adults.
Describe sleep in infancy.
Infants spend 13-12 hours asleep. 65% of this is NREM, and 35% is REM.
Infants are beginning to move more, explaining the increased NREM, as NREM replenishes the body.
Describe sleep in childhood.
Children spend 10-11 hours asleep. 75% of this is NREM, and 25% is REM.
Describe sleep in adolescence.
Adolescents spend 8.5 hours asleep. 80% of this is NREM, and 20% is REM.
Describe sleep in old age.
The elderly spend 5-6 hours asleep. 80% of this is NREM, and 20% is REM.
What are the four main types of brainwaves?
Beta
Alpha
Theta
Delta
What is amplitude?
A brainwave’s height and intensity.
What is frequency?
The number of brainwaves that occur per second.
Describe beta waves.
Low amplitude, high frequency.
Describe alpha waves.
Medium-low amplitude, medium-high frequency.
Describe theta waves.
Medium-high amplitude, medium-low frequency.
Theta waves also experience ‘K complexes (spikes) and sleep spindles (Spurts of high activity).
Describe delta waves.
High amplitude, low frequency.