3.11. Ultraradian and Infradian Flashcards
How is the sleep-wake cycle measured?
Through EEGs, roughly 90-100 mins in length.
How many cycles every night?
Roughly 5
How many stages in the sleep-wake cycle?
5
Stage 1 of sleep-wake cycle
NREM: Light sleep, muscle activity slows (twitching happens)
Stage 2 of sleep-wake cycle
NREM: breathing and heart slows
Stage 3 of sleep-wake cycle
NREM: deep sleep begins
Stage 4 of sleep-wake cycle
NREM: very deep sleep, limited muscle activity
Stage 5 of sleep-wake cycle
REM: brain activity resembles that when awake
Muscle paralysis happens (to stop activity when acting out a dream)
What is the basic rest activity cycle?
- Not as obvious as the sleep cycle but 90-100 cycles occur during the awake period.
- We move progressively from a state of alertness to fatigue.
- Endogenous and exogenous pacemakers work together to keep us in time
Strength (under 24 hrs): Ericsson
- Ericsson found elite violinists limited their practice to no more than 90 mins at a time and napped frequently to recover from practice sessions
- Common amongst athletes, chess players and writers
Weakness (under 24 hrs): sleep diffs
Sleep diffs may be biologically determined through genetics
Weakness (under 24 hrs): Tucker
Recorded large diffs in sleep, duration, time to fall asleep and time spent in sleep stage of ppts spending 11 nights in a controlled lab.
Weakness (under 24 hrs): validity
Low ecological validity testing sleep stages in a lab with EEG - not like real life
How long does a woman’s reproductive cycle last?
- Lasts about 1 month on average
What is a woman’s reproductive cycle regulated by?
- Regulated by hormones which promote ovulation or stimulates the uterus for fertilisation
When does ovulation occur?
Roughly half way through the menstrual cycle, when oestrogen levels peak (lasts 16-32 hrs)
What happens after ovulation?
progestogen levels increase in preparation for the possible implantation for an embryo in the uterus.
What is seasonal affective disorder?
Seasonal variations in mood, during the winter months where there are longer hours of darkness, which increases our melatonin.
- This has a knock on effect of serotonin levels (leads to depression)
Strength (over 24 hrs): Russell
- Daily rubbed underarm sweat from one group of women onto the upper lip of a different group of women that were separated.
- 68% of their menstrual cycles synchronised.
- Pheromones (exogenous) of others have an effect on us.
Strength (over 24 hrs): RWA
- Light therapy has been created based on research into rhythms
- It has an 80% success, useful in the short term
