Sleep and circadian rhythms Flashcards
What is the study of sleep called?
Polysomnography
Name the three types of scans that are used in the study of sleep
EEG, EOG, EMG
Name the two types of brain activity waves during wakefulness, and name when they occur
Beta, during brain activity, and alpha, when the person is resting
What brain wave activity characterises stage 1 sleep?
Theta waves
What two features is stage 2 sleep characterised by?
Sleep spindles (rapid but short bursts of activity) and k complexes (high amplitude but slow)
Stage 3 sleep involves what brain waves?
Delta
What is another term for stage 3 sleep?
Deep sleep/slow wave sleep
What brain activity waves occur in REM sleep?
Beta and theta
How long does it take to cycle between all four stages and back?
90 mins
What was discovered by Dement and Kleitman in 1957?
Dreams
What % of dreams are 1. sad, angry or anxious, 2. happy, 3. of a sexual nature?
- 64%
- 18%
- 1%
What is Allan Hobsonsnactivation-synthesis hypothesis of dreaming?
The brainstem is activated during REM sleep and sends a signal to the cortex which creates images with actions and emotions from memory
There is no logic in dreaming however, when awake, the person tries to organise the content into a logical story
There is no meaning of dreams, however they are based on the persons experience
What is another name for Valli and Revonsuos coping hypothesis of dreaming?
The clinico-anatomical hypothesis
What does the clinico anatomical hypothesis/coping hypothesis of sleep suggest?
We dream about things we find threatening in our lives and dreams are biologically adaptive, tending to lead to enhanced coping strategies
What evidence supports the co-ping hypothesis of dreaming?
Problem solving occurs during sleep
What is the role of adenosine?
Accumalates during the day and promotes sleep, signals that there is very little energy and that we have used a lot of our energy already
Patients who had continuous sleep and would only wake up to eat and drink had damage to what brain area?
The base of the brain
Damage to what brain area is involved in insomnia patients?
Ventro-lateral preoptic area
What brain area is involved in wakefulness and who discovered the region?
The brain stem and Moruzzi and Mogoun, 1949
What is the name of the system operating during wakefulness?
Reticular activating system
What is the RAS
Composed of several nuclei that project to the forebrain and promote arousal
What are the different nuclei in the RAS
- Locus coeruleus
- Raphe nucleus
- Tuberomammillary nucleus
Nucleus basalis of Maynert