ultradian and infradian rhythms Flashcards
infradian rhythms
biological rhythms that take longer than 24 hours to complete full cycle
ultradian rhythms
biological rhythms that last under 24 hours
2 topics in ultradian rhythms
sleep cycle
basic rest activity cycle (brac)
sleep cycle
one fulll cycle = 90 min
5 distinct stages of sleep
cycle repeats itself loads per night
What happens during Stage 1 of sleep?
Light sleep, muscle activity slows, and it’s easy to be woken. Alpha waves are present.
Stage 2 of sleep
slightly deeper sleep, breathing and heart rate slow. Theta waves are present.
stage 3 of sleep
Deep sleep begins, it’s harder to wake someone, and slow delta waves start appearing.
stage 4 of sleep
Very deep sleep, it’s difficult to wake someone, and the brain produces delta waves. Rhythmic breathing occurs with limited muscle activity.
stage 5 of sleep
Rapid eye movement occurs, dreaming happens, brainwaves speed up, the heart rate increases, breathing is rapid and shallow, and the body is paralyzed.
kleitman 1969
He suggested that a 90-minute cycle of alertness followed by fatigue continues throughout waking hours.
what was the key finding from Ericsson et al. (1993) regarding BRAC in violinists?
The best performers practiced in 90-minute sessions with breaks in between to recharge.
ao3 strength ultradian
p- supporting research that suggests there’s qualitivately different stages in sleep
e- dement and kleitman investigated when dreaming occurs in sleep, monitored EEG records and found that participants woken during REM sleep reported dreams 80-90% of the time.
E – REM activity during sleep correlated with dreaming, brain activity varied
according to how vivid dreams were.
L – The study suggests that REM sleep is a distinct ultradian rhythm and an
important component of the ultradian sleep cycle.
ao3 strength ultradian
P – Research support for the BRAC comes from studies of elite performers.
E – Ericsson (2006) found elite violinists practice sessions were usually limited
to a duration of no more than 90 minutes, with practice distributed during the day
into 90 minute segments.
E – His research also indicated that violinists frequently napped to recover from
practice and he discovered the same pattern among other musicians, athletes,
chess players and writers.
L – This supports the existence of a 90 minute ultradian cycle of alertness and
fatigue.
2 topics in infradian rhythms
- menstrual cycle
- seasonal affective disorder
menstrual cycle
-influenced by monthly changes in hormone levels
-which regulate ovulation
- average length of cycle - 28 days
- between 24-35 days = normal