Ultradian Rhythms Flashcards
(16 cards)
What is an ultradian rhythm?
A type of biological rhythm with a frequency of more than one cycle in 24 hours, such as the stages of sleep.
What characterizes ultradian rhythms?
Ultradian rhythms last less than 24 hours, meaning there is more than one cycle within a 24-hour period, such as the sleep cycle and the wake cycle.
How many stages are there in the sleep cycle?
There are five stages of sleep that occur throughout the night.
What is the duration of each sleep cycle?
Each sleep cycle spans approximately 90 minutes.
What are the characteristics of stages 1 and 2 of sleep?
Stages 1 and 2 are light sleep where the person can be easily woken. Brain waves are high frequency and short amplitude (alpha waves) in stage 1, and continue with occasional sleep spindles in stage 2.
What happens during stages 3 and 4 of sleep?
Stages 3 and 4 are deep sleep, characterized by delta waves with lower frequency and higher amplitude, making it difficult to rouse someone. Metabolic rate is low and growth hormones are released.
What occurs during REM sleep?
In stage 5, REM sleep, the body is paralysed, brain activity speeds up, and theta waves are produced. Rapid eye movement occurs, and this stage is highly correlated with dreaming.
What is the basic rest activity cycle?
The basic rest activity cycle is a 90-minute cycle found during sleep that continues during the day, transitioning from a state of alertness to physiological fatigue.
How long can the human mind focus according to the basic rest activity cycle?
The human mind can focus for a period of 90 minutes.
What happens towards the end of the 90-minute focus period?
Towards the end of the 90 minutes, the body begins to run out of resources, resulting in loss of concentration, fatigue, and hunger.
What is the Waking Rest-Activity Cycle?
The Waking Rest-Activity Cycle consists of activity for 90 minutes followed by a rest period of 20 minutes.
Why are there coffee breaks at 10:30 AM?
Coffee breaks at 10:30 AM occur because the morning is typically split into two 90-minute cycles.
What practice pattern did Ericsson et al. (1993) find among the best violinists?
Ericsson et al. found that the best violinists practiced for three sessions during the day, each lasting no more than 90 minutes, with breaks in between to ‘recharge’.
What did Dement and Kleitman (1957) find in their study on sleep patterns?
Dement and Kleitman found evidence for stages of sleep, specifically REM sleep, which correlated with dreaming.
What did Tucker et al. (2007) discover about individual differences in sleep?
Tucker et al. found large individual differences in sleep duration, time to fall asleep, and time spent in each sleep stage, particularly in deep sleep (stages 3 and 4).
What does the research suggest about generalizing sleep stage differences?
The research suggests that individual differences in sleep stages are linked to biology, making it difficult to generalize findings to the wider population.
