Altered States of Awareness

Question 1

Circadian rhythms

Answer 1

a behavioural or physiological cycle that takes place over 24 hours

• sleeping in the dark, waking in the light helps keep the rhythm in phase
• body temperature peaks in the afternoon and lowest in the early morning

Question 2

What do circadian rhythms include?

Answer 2

Sleep/ awake cycle 
body temperature 
blood pressure 
secretion of growth hormones 
blood sugar levels

Question 3

Sleep Cycle

Answer 3

Relates to the level of awareness - morning/ lower levels

• SCN, cluster of nerve cells located in the hypothalamus
• Light is our external cue to synchronise the body clock
• SCN controls the sleep/wake cycle by sending messages to the pineal gland to adjust melatonin levels or regulate levels of hormones and neurotransmitters

Question 4

Influences on circadian rhythms

Answer 4

• melatonin = hormones that tell our body whether it should be awake or asleep
• jet lag = new environmental time cues differ from our biological clock and Cr orrurs when travelling through different time zones. Results in fatigue, loss of concentration, increased irritability

Question 5

Theories on why we sleep

Answer 5

• energy conservation
• repair and restoration
• memory and consolidation

Question 6

What is energy conservation?

Answer 6

Metabolic rate is lower, therefore, not as much energy being used when sleeping
Temp lowers, body doesnt need to work as hard

Question 7

What is repair and restoration?

Answer 7

Substantial cell repair occurs in the body when sleeping

During sleep, immune system strengthens and eliminates waste products from muscles

Question 8

What is memory consolidation?

Answer 8

Allows brain to consolidate learning and in particular to make sense of memory and store in logical order
Get plenty of deep non-REM sleep or REM in second half > improve their ability to perform tasks

Question 9

Stages of sleep

Answer 9

NREM = Stage 1-4
REM = Stage 5
EEG = measures electrical activity (brain wave patterns) in brain through stickers on head
Amplitude and frequency of brain waves differ when we enter different stages of consciousness
Each cycle lasts 90 - 110 mins of NREM and REM. Average person is likely to flow into stages 1-4 four - six times a night

Question 10

Stage 1

Answer 10

Relaxed wakefulness (approx 10 mins)
Brain = alpha brain waves present on EEG, reduced brain activity
irregular fast and slow amplitude on EEG
Body = rolling eye movement
slowed breathing and heart rate
reduced muscle activity
hyphogic jerk

Question 11

Stage 2

Answer 11

approx 20 mins
Brain = presence of sleep spindles and K - complexes
Body = Medium amplitude in muscle movement - no eye movement
Temp, heart rate, breathing and blood pressure continue to drop

Question 12

Stage 3

Answer 12

SWS (slow wave sleep) approx 15 mins
Brain = slow waves appear - delta
travel to stage 4
delta waves make up 20-50% of brainwave activity
Body = medium to low amplitude in muscle tension
no eye movement

Question 13

Stage 4

Answer 13

SWS - deepest stage of sleep
Brain = delta waves account for more than 50% of activity
Body = Little t no muscle movement
breathing at its slowest and deepest
hard to wake someone > if awoke person is confused and disorientated
Amount of SWS = how restored a person feels

Question 14

Stage 5

Answer 14

REM
sleep lightens and moves back through stage 4-3-2 to a unique stage
Rapid eye movement = eyes move around
Brain = dreaming is reported
EEG in REM similar to an awake person
Beta and some alpha waves present
Body = pulse, breathing, blood pressure quickens, eyes move very quick
deepest sleep in first cycle, dream in last cycle