Sleeping and dreaming (topic 9) Flashcards
what are the effects if sleep deprivation
–trouble witht hinking and concentration
–accidents
–mood changes
–weakened immunity
–risk of heart disease
–high blood pressure
how much sleep do you need
0-2m: 12-18h
3-11m: 14-15h
1-3yrs: 12-14h
3-5yrs: 11-13h
5-10yrs: 10-11h
10-17yrs: 8.5-9.25h
+17yrs: 7-9h
REM (rapid eye movement)
-stage which dreaming occurs.
-brain waves are the same as when a person is awake
-sensory blockade
-signaks in the pons shuts off neirons in the spinal cord, preventing movement
-20% in adults, 50% in infants
stage 1
-when relaxed: alpha waves
-when fallen asleep: theta waves (irregular and slow)
-breathing, heart rate slow down, temp decreases.
stage 2
-conciousness if the outside world fades
-muscle activity decreases
-brain activity slows down, mainly theta waves
-busts of brain activity can be found (spindles)
-light sleep–> sleep
stage 3
-brain shows delta waves
-virtually no eye movements and body is relaxed
-difficut to wake up
stage 4
-deep sleep very difficult to wake up
-heart rate, temp and blood pressure at lowest
-no eye movements
what is the sleep cycle
the changign of stages during your sleep. each cycle takes 90 minutes
what are circadian rhythms
psychological and behavioural characteristics tha follow a daily pattern - a 24 hour cycle
(e.g., sleep-wake cycle, body temp and hormones)
what is the difference between the sleep-wake cycle and the sleep cycle
the sleep cycle is when a person is asleep. while the sleep wake cycle is when a person is asleep and awake
what are ultradian rhythms
bodily rhythms that last less than a day (24h)
(e.g., blinking, appetite, sleep cycle)
what is the saprachaismatic nucleus (SCN)
the SCN is a type of biollogical clock that keeps our circadian rhythms on close to a 24 hour cycle. it is effected by both endogenous (internal) and exogenous (external) influences
internal effects on sleep
hormones:
aldrenaline
melatonin
–adrenaline makes us feel more alert and prepared for action
–if there is high levels of aldrenaline then it will be hard to go to sleep
–to prevent this calmin gactivities should be done before bed
–melatonin is made in the pineal gland. it is referred as the sleep hormone
–levels increase in late evening and throughout the night to bring sleep
external factors affecting sleep
–zeitgebers refers to the syncing of our biological clocks to external cues such as light, dark, seasons, etc.
–stress
–medication
what a person eats or drinks
siffre 1975
aims
–to investigate thee effects of living underground in a cave without external cues on the 24 hour sleep wake cycle