Biopsychology: Biological Rhythms

Question 1

What are the three types of biological rhythms

Answer 1

• Infradian
• Circadian
• Ultradian

Question 2

Define Infradian Rhythm

Answer 2

a type of biological rhythm with a frequency of less on than cycle in 24 hours
e.g. menstrual cycle

Question 3

Define Ultradian Rhythm

Answer 3

a type of biological rhythm with a frequency of more than one cycle every 24 hours
e.g. stages of sleep

Question 4

Define Circadian Rhythm

Answer 4

a type of biological rhythm subject to a 24 hour cycle

e.g. sleep/wake cycle

Question 5

Outline stages of sleep:

Answer 5

Ultradian Rhythm:
1+2 = light sleep easily woken, brain waves slow and rhythmic (alpha then theta)
3+4 = Deep sleep, difficult to wake, slower brain waves (delta)
5 = REM (rapid eye movement) body is paralysed but brain activity speeds up. REM associated with dreaming

Question 6

Outline sleep/wake cycle

Answer 6

Circadian rhythm:

feel drowsy at night and alert through the day due to the effect of daylight

Question 7

Outline Siffre’s Research into the sleep/wake cycle:

Answer 7

lived in texan cave for 6 months

free running biological rhythm settled to 25 hours

Question 8

Outline Aschoff and Wever’s Research into the sleep/wake cycle:

Answer 8

Pps spent 1 month in WWII bunker deprived of natural light

All but one (29 hours) showed a 24-25 hour sleep/wake cycle

Question 9

Outline Folkard’s Research into the sleep/wake cycle:

Answer 9

12 pps lived in a cave for 3 weeks
Told to sleep between 11:45pm - 7:45am (as said on clock)
Clock Spd up so 24 hours only lasted 22
Only 1 pps could adjust to this
Shows strong free running circadian rhythm cant easily be overridden by environmental changes

Question 10

Outline the menstrual cycle research:

Answer 10

Infradian Rhythm:
Stern and McClinkton
29 women with irregular periods
pheromones from women gathered and worn on pads by other women
68% women experienced changes in period bringing it closer to ‘ouder donor’