Chapter 33 Rest and sleep Flashcards
define rest
condition where your body is in a state of decreased activity and consequent feeling of being refreshed
define sleep
a state of rest accompanied by altered consciousness and relative inactivity
sleeping is a complex rhythmic state involving repeated cycles, and each cycle representing different phases of what?
body and brain activity
Name the 2 systems in the brain stem that work together to control the cyclic nature of sleep
RAS (Reticuar Activating System)
bulbar synchronizing region
Which specific part of the brain facilitates reflex and voluntary movements as well as cortical activities related to state of alertness?
RAS
The fibers of the RAS have connections that relay impulses into which 2 places?
cerebral cortex
spinal cord
When is “wakefulness” in the RAS activated?
activated with stimuli from the cerebral cortex and from periphery sensory organs and cells
Name the 3 sensations that produce wakefulness by means of peripheral organs and cells
pain
pressure
noise
Where would you find an involuntary control center for sleeping and waking?
hypothalamus
Injury to the hypothalamus may cause someone to sleep for abnormally ____ periods
long
List some of the NT involved in the sleep process
(list 5 involved with excitation)
(give the name/abbreviation of the one necessary for inhibition)
excitation: NE, ACh
dopamine, serotonin, histamine
inhibition: GABA (gamma-aminobutyric acid)
What type of clocks assoc. with sleep exist with plants, animals, and humans?
Rhythmic biologic clocks
Circadian Rhythms complete a full cycle every ___ hours
every 24 hours
When there is an interference with your normal cycle of circadian rhythm, what is this called?
- circadian disruption
or chronodisruption
For nurses that work graveyard, the exposure to light at night during normal sleeping hours is called what?
night-shift chronodisruption
When do problems of desyncronization occur?
when sleep-wake patterns are frequently altered and the person attempts to sleep during high-activity rhythms or to work when the body is physiologically prepared to rest
Name the 2 major stages of sleep
NREM: Non rapid eye movement
REM: Rapid eye movement
How much of our sleep is NREM sleep?
75% total
How many stages of NREM sleep are there and what happens during them?
4 stages
Stage I and II: light sleep states
Stage III and IV: deep sleep or delta sleep (slow wave)
define arousal threshold
the intensity of stimulus required to awaken
greatest in stage IV NREM
which Nervous System dominates during NREM sleep?
parasympathetic
How much of a person’s nightly sleep time is consumed by REM sleep?
20-25%
REM sleep is believed to be essential to mental and emotional equilibrium and plays a role in what 3 things?
- learning
- memory
- adaptation
If you are deprived of REM sleep for several nights, what does your body to to ensure you get a constant amount of it?
it will increase the amount of time spent in REM sleep in successive nights, this is called REM rebound
How many cycles of sleep will a person go through each night and on average how long does each cycle last?
four to five cycles
each cycle on average 90-100 minutes
what is the name for the alternating between NREM and REM sleep during cycles?
sleep architechture
Which stage of NREM sleep is a transitional stage between wakefulness and sleep?
Stage I
In Which stage of NREM sleep does a person finally fall into a stage of sleep but can be aroused with relative ease and this constitutes for 50 to 55% of sleep
Stage II
Which stage of NREM sleep counts for about 10% of sleep and depth of sleep increases and arousal starts becoming difficult?
Stage III
In which stage of NREM sleep does a person reach the greatest depth of sleep “delta sleep”?
Stage IV
REM sleep enters from which stage of NREM sleep and then reenters NREM sleep at which stage?
Stage II for both
