Chapter 8 - Higher Functions and Perception Flashcards
What can be distinguished by the brains small electric field?
Whether or not it is:
Alert
At rest/asleep
The phase of sleep
What are the 5 stages of sleep?
1 - drowsiness - lasting 10 minutes
2 - light sleep with short periods of fast EEG waves - 20minutes
3 - deeper sleep
4 - deep, slow wave sleep - difficult to be aroused
5 - REM sleep - associated with dreaming
How long is a sleep cycle?
90 mins
How many sleep cycles are there in a night of sleep?
4 - 5
What happens to REM sleep as the night progresses?
It gets longer.
What is so special about REM sleep?
It rejuvinates your brain.
What happens if someone becomes sleep deprived?
Mood swings - irritability
Increased fatigue
Reduced concentration
Lack of attention
Increased risk of sensory illusions
Individual becomes prone to errors
Progressive decline in intellectual performance
What can prolonged sleep deprivation lead to?
increased severity of symptoms
How many sleep points does 1 hour of sleep give you?
2 points
How many sleep points does 1 hour of being awake take from you?
1 point.
What is the maximum amount of sleep point you can get in one nights sleep?
16
Why must you try to get more sleep if you go into sleep debt?
Sleep debt is cumulative so the only way to make up for it is to sleep for at least 8 hours in numerous sittings.
What happened to the performance reduction with increased altitude?
it gets even worse with altitude
What is the circadian rhythm?
Fluctuations of:
Body temperature; Blood pressure; Heart Rate; Sensory acuity; Adrenal gland output; Brain nuero-transmission level.
Usuallly locked to 24 hours but without visual cues - Zeitgebers - locks to 25 hours
What is circadian disrhythmia?
Where your circadian rhythm is incorrect for the time zone you are in, usually due to jet lag.
What is transmeridian desynchronisation?
Jet lag
How long does it take for your circadian rhythm to adjust to a new time zone?
1 day for every 90 minutes difference in time zones.
When is body temperature lowest and what does this mean for performance?
around 0500/0600
performance is least efficient - circadian low.
When is body temperature highest?
Around 2000
When is sleep longer and more refreshing?
When taken when body temperature is falling.
When is the effect of jet lag the worst?
When travelling to the east (against the sun)
How do you work out jet lag?
Jet lag = day length experienced - body clock(25)
What is the recommended jet lag recovery technique?
If stop over less than 24 hours - stay on YOUR local time
If more than 24 hours - change to new local time asap
If equal to 24 hors take a little rest period on arrival.
What is the effect of alcohol/heavy meals on REM sleep?
It is reduced considerably
What happens to a person within 5 minutes of waking up from a nap?
Their responses & reactions are slow
How long does a nap have to be in order to be restorative?
at least 10 minutes
What is a microsleep and what are the dangers of them?
A sleep for a fraction of a second
A person can be unaware of them
They do not assist in reducing sleepiness.
What types of fatigue are there?
Short term (acute) - physical/mental exersion; crew scheduling; long duty period; lack of food; jet lag
Long term (chronic)
fatigue is cumulative
What is the difference between bottom up and top down processing?
Bottom up takes sensory information and then assembles a mental model from info recieved
Top down compares information received with past experience and knowledge.
