Sleep Flashcards
Sleep
an altered state of consciousness that features the suspension of awareness of the external environment and is accompanied by a number physiological changes in the body
Sleep pattern
rhythms of sleep and walking so steady that they continue for many days, even when clocks and external light and dark cues have been removed.
Melatonin
a hormone that is secreted to regulate the sleep wake cycle and cause drowsiness
Pineal gland
a gland located in the center of the brain that helps regulate body rhythms and sleep cycles
EOG (Electroculargraph)
a machine used to detect, amplify, and record the electrical activity of the muscles surrounding the eyes
EMG(Electromyograph)
a machine used to detect, amplify, and record the electrical activity created by active muscles of the body, using electrodes attached to the skins surface
hypnogogic state
a state that is experienced just before falling asleep and is characterised by slow, rolling eye movements and deep relaxation
Polysomnography
intensive study of a sleeping person involving simultaneous monitoring and recording of various physiological responses during the course of their sleep
How much of our sleep time is spent in NREM and how much is spent in REM
80,20
How much does each cycle of sleep last
approx. 90 minutes
What increases as the night progresses and what decreases (REM and NREM
Periods NREM sleep decrease and REM sleep increases (REM sleep lengthens as the night progresses)
REM (Rapid Eye Movement)
Definition
What happens?
A type of sleep characterised by an increase in physiological functions as parts of the body are in states of arousal, however at the same time the muscles of the body are in a state of paralysis.
dreaming random, fast, sawtooth pattern of beta like waves heart rate increases breathing becomes more rapid and irregular blood pressure varies genitals become aroused eyes dart around sockets in state of atonia- complete paralyisis sort and consolidate memories may increase dramatically when there is some sort of emotionally charged event e.g. death of family member lasts an average of 90 minutes per night essential for restoration of the minds
What is essential for the restoration of the mind and what is essential for the restoration of the body?
REM= mind NREM= body
atonia
a lack of time in the muscles, or muscle paralysis, experienced during dream sleep
Why is REM considered paradoxical sleep
Although brainwaves resemble alertness, REM sleep is actually considered quite a deep sleep because it is difficult to to wake an individual in this stage.
NREM
definition
What happens?
A type of sleep that is broken into 4 stages where the sleeper falls into a deeper sleep as the stages progress; characterised by relaxation of the muscles, a slowing down of physiological functions and brainwaves that decrease in frequency and increase in amplitude.
slower heart and respiratory rates increase in growth hormone secretion vigorous stimulation required to wake dream free 80% of the time essential for the restoration of the body
Stage 1 NREM
What waves does it have
How long does it last
What happens
alpha and theta waves, 2-10 minutes, hypnogogic state, hypnic jerk
heart rate slows
- breathing becomes irregular
- muscles relax— this may trigger a hypnic jerk
- aka light sleep
- marked by alpha brainwaves - theta waves begin to appear
- brainwaves become higher in amplitude and lower in frequency
- lasts for approx. 2-10 minutes
- people awakened may or may not feel as though they have been sleeping
What is a hypnic jerk?
When does it occur?
a reflex muscle contraction that occurs during stage 1 NREM
Stage 2 NREM
What waves does it have
How long does it last
What happens
theta waves, 20-30 minutes
- body rate drops
- heart and respiratory rates continue to slow down
- can be woken by a loud noise
- theta waves
- sleep spindles- seem to mark the true boundary of sleep
- k-complex- thought to be involved in memory consolidation
- lasts for approx. 20-30 minutes
- if a person is awakened with 4 minutes of sleep spindles they will report they were asleep
sleep spindles
What is it?
at what stage is it experienced?
a type of brain activity characterised by a short burst of high-frequency brainwaves, experienced during stage 2 NREM sleep
k-complex
What is it?
at what stage is it experienced?
a short burst of high amplitude brainwaves, experienced in stage 2 NREM sleep
Stage 3 NREM
What waves does it have
How long does it last
What happens
theta and delta waves, 3-20 minutes
- physiological responses begin to steady
- theta waves continue to appear- delta waves also begin to appear (aka the emergence of SWS)
- presence of delta waves= further loss of consciousness
- transitional stage
- last for approx. 3-10 minutes
- more difficult to awaken
SWS (slow wave sleep)
a sleep state characterised by the emergence of delta waves; SWS is experienced during stages 3+4
Stage 4 NREM
What waves does it have
How long does it last
What happens
deep sleep, delta waves
- pure delta waves
- will wake in confusion
- may not recall hearing noise
- may take a few minutes to orientate
- can last for approx. 20-30 minutes but decreases as the night progresses
- appearance of sleep problems such as sleep-walking and bed-wetting
