Ultradian Rhythms

Question 1

What is an ultradian rhythm?

Answer 1

A biological rhythm with a period less than 24 hours

Question 2

Stage 1&2 of sleep stages?

Answer 2

Easy to wake the sleeper- in light sleep
Slow alpha waves
Sleep spindles (involved in brain plasticity and diminish our response to outside stimuli when sleeping) occur more regularly during stage 2

Question 3

Stages 3&4 of sleep stages?

Answer 3

Very difficult to wake the sleeper- slow and deep delta waves- greater amplitude

Question 4

Stage 5 of sleep stages?

Answer 4

Dreaming occurs
CNS is cut off
REM sleep- the eyeballs are active. Body paralysed but brain activity is the same as when awake

Question 5

Dement and Kleitman (1957)?

Answer 5

Studied 9 adults sleep patterns by EEG
Were taken to a sleep lab
Controlled for caffeine and alcohol
Woken at specific intervals during sleep- asked if they were dreaming/what about
Findings showed positive correlation between REM sleep and dreaming
Vertical eye movement = dreams of climbing ladders
Horizontal eye movements = dreams of watching people throw tomatoes at eachother

Question 6

Strengths of Dement and Kleitman?

Answer 6

Well-controlled study
Removed any confounding variables- alcohol/caffeine
High in reliability

Question 7

Replications of Dement and Kleitman?

Answer 7

Have supported the findings
Good validity- REM sleep is associated with dreaming

Question 8

Limitations of Dement and Kleitman?

Answer 8

Small sample size- findings are difficult to generalise
Research was carried out in the 1950’s- lacks temporal validity
Digital technology e.g. smartphones did not exist- didnt interfere with ultradian rhythms- new research should be conducted