Ultradian Rhythms

Question 1

What is an ultradian rhythm?

Answer 1

Something that happens more than once in a 24 hour period (cycles of the stages of sleep)

Question 2

How many cycles of sleep will a person go through on average?

Answer 2

Five

Question 3

What are the cycles made up of?

Answer 3

NREM (non-rapid eye movement and REM (rapid eye movement)

Question 4

What is stage 1-4?

Answer 4

NREM sleep

Question 5

What is stage 5?

Answer 5

REM sleep

Question 6

What happens during stage 1?

Answer 6

Shallow sleep, heart rate slows down and body temperature falls, might experience hallucinations, alpha waves

Question 7

What happens during stage 2?

Answer 7

EEG pattern becomes synchronised, larger slower theta waves interrupted by fast spiking activity

Question 8

What happens during stage 3?

Answer 8

Heart rate and temperature continues to fall, delta waves start to dominate EEG pattern

Question 9

What happens during stage 4?

Answer 9

Deep sleep, very hard to wake someone up, delta waves, sleepwalking might occur

Question 10

What happens during stage 5?

Answer 10

REM sleep, EEG show pattern similar to the one displayed when awake, dreams occur

Question 11

What did Dement and Kleitman able to show?

Answer 11

Through the use of EEG that dreams occur mainly at stage 5 of sleep

Question 12

Who took part in their study?

Answer 12

9 adults which took place in a sleep lab. Electrodes were attached around the participants eyes to measure eye movement and the scalp to measure brain activity

Question 13

What did they find?

Answer 13

• All pps displayed REM activity
• REM periods lasted between 3-50 minutes
• REM activity had a regular pattern to it
• Most dreams were reported during REM sleep

Question 14

What are 4 evaluation points?

Answer 14

• Lacks temporal validity
• Lacks population validity
• Lacks ecological validity
• Lacks internal validity