Lesson 12 - Ultradian and Infradian Rhythms

Question 1

What is an Ultradian rhythm ?

Answer 1

A cycle that lasts less than 24 hours.

Question 2

What does 5 stages of sleep consist off ?

Answer 2

Rapid eye movement (stage 5) and Non rapid eye movement (which consists not stages one, two, three and four). Cycle repeats evert 90 minutes

Question 3

What did Kleitman say ?

Answer 3

He referred to the cycle as the Basic Rest Activity Cycle (BRAC) and suggested that it continues during the day.

Question 4

What is a strength of Ultradian Rhythms?

Answer 4

Ericsson studied group of elite violinists and found that among this group practice sessions were limited to 90 mins. Violinists would nap to recover from practice, Fits with the BRAC

Question 5

What is a weakness of Ultradian Rhythms?

Answer 5

Tucker suggests that there are individual differences in ultradian rhythms which are biologically determined and could be even genetic. He studied PPS over 11 consecutive days and nights in a lab. Differences were found in sleep duration and time taken to fall asleep

Question 6

What is an Infradian Rhythm ?

Answer 6

A cycle that lasts longer than 24 hours. E.g. menstrual cycle

Question 7

What is a strength of Infradian Rhythms ?

Answer 7

Infradian rhythms affect behaviour. Penton-Vaak found that women prefer feminised male faces foe long term relationship, but more masculine faces during ovulation.

Question 8

What is a weakness of Infradian Rhythms ?

Answer 8

Menstrual cycle is not only governed by infradian rhythms. Cycles can synchronise