Ultradian

Question 1

A03 DUFFY

Question 2

What are the sleep cycles

Answer 2

Typically, a person would begin a sleep cycle every 90-120 minutes resulting in four to five cycles
per sleep time, with each stage lasting between 5 to 15 minutes.
The first sleep cycles each night have relatively short REM sleeps and long periods of deep sleep
but later in the night, REM periods lengthen and deep sleep time decreases.

Question 3

Stage 1: The lightest stage of NREM sleep.

Answer 3

-A drowsy sleep stage that can be easily disrupted causing awakenings or arousals.
-Muscle tone throughout the body relaxes and brain wave activity begins to slow.

Question 4

Stage 2: The first actual stage of defined NREM sleep.

Answer 4

Awakenings or arousals do not occur as easily as in Stage 1.

Brain waves continue to slow with bursts of activity known as sleep spindles and K complexes.

Sleep spindles and K complexes protect the brain from awakening.

Question 5

Stage 3: Deep NREM sleep (the deepest stage of sleep)

Answer 5

The most restorative stage of sleep, least likely to be disturbed by external stimuli.

Consists of delta waves or slow waves.

Parasomnias (sleepwalking, sleep talking, night terrors) occur during this stage.

Question 6

Stage 4: Rem Sleep

Answer 6

Breathing becomes rapid, irregular, and shallow.

Eyes move rapidly in various directions under the eyelids.

Limb muscles are temporarily paralysed (muscle atonia), preventing movement.

Brain activity increases to levels similar to being awake — this is when vivid dreaming typically occurs.

Heart rate and blood pressure increase

Question 7

A03 - Dement and Kleitman

Answer 7

1. Research supports the distinct stages in sleep
2. Dement and Kleitman (1957) monitored the sleep patterns of nine adult participants in a
   sleep lab.
3. Brainwave activity was recorded on an EEG and the researchers controlled for the effects of
   caffeine and alcohol. REM activity during sleep was highly correlated with the experience of
   dreaming, brain activity varied according to how vivid dreams were, and participants woken
   during dreaming reported very accurate recall of their dreams.
4. The study suggests that REM (dream) sleep is an important component of the ultradian
   sleep cycle.

Question 8

WHATS AN ULTRADIAN RHYTHM

Answer 8

Biological rhythms which last less than 24 hours, e.g. stages of

sleep