UNIT 3THE CONSCIOUS SELF

AREA OF STUDY 1: MIND, BRAIN & BODY

CHARACTERISTICS & PATTERNS OF SLEEPNon-Rapid Eye Movement sleep (NREM sleep)Rapid Eye Movement sleep (REM sleep)

CHARACTERISTICS & PATTERNS OF SLEEPNon-Rapid Eye Movement sleep (NREM sleep)Rapid Eye Movement sleep (REM sleep)

CHARACTERISTICS & PATTERNS OF SLEEPNREM SLEEP

The characteristics of NREM sleep include:

•The brain is active, but not as active as REM sleep or normal waking consciousness

•May be the time when the body recovers, repairing body tissue, removing waste products and replenishing neurotransmitters

•Consists of 4 different stages in which the sleeper progresses from light sleep to deep sleep over the course of the night

BEING AWAKE BEING ASLEEP

HYPNAGOGIC STATE

CHARACTERISTICS & PATTERNS OF SLEEPNREM SLEEP – STAGE 1

STAGE 1 CHARACTERISTICS

•Drift into and out of a true sleep state

•Decrease in heart rate, respiration, body temperature and muscle tension

•Hypnic jerks occur

•EEG shows a decrease in alpha waves, replaced by theta waves

CHARACTERISTICS & PATTERNS OF SLEEPNREM SLEEP – STAGE 2

STAGE 2 CHARACTERISTICS

•A light stage of sleep in which someone can be said to be truly asleep

•Body movements lessen, breathing becomes more regular, blood pressure and body temperature continue to decrease

•EEG shows mainly theta waves (but slightly lower in frequency and higher in amplitude than Stage 1)

•Sleep spindles periodically appear (brief burst of higher frequency brain waves)

•K-complexes appear in response to external stimuli (bursts of low frequency, higher amplitude waves)

CHARACTERISTICS & PATTERNS OF SLEEPNREM SLEEP – STAGE 3

STAGE 3 CHARACTERISTICS

•The start of the deepest period of sleep (moderately deep sleep)

•Heart rate, blood pressure and body temperature continue to decrease and breathing rate is slow and steady

•EEG shows that delta waves begin to appear (20-50% of brain waves)

•These delta waves indicate the onset of slow-wave sleep (SWS)

CHARACTERISTICS & PATTERNS OF SLEEPNREM SLEEP – STAGE 4

STAGE 4 CHARACTERISTICS

•The deepest stage of sleep (called very deep sleep)

•Our muscles are completely relaxed and barely move

•Delta waves dominate the EEG recording

•When woken during Stage 4 sleep, person experiences sleep inertia

•Sleep-walking, sleep talking and night terrors may occur

CHARACTERISTICS & PATTERNS OF SLEEPREM SLEEP

REM SLEEP CHARACTERISTICS

•The eyeballs rapidly move beneath the closed eyelids

•EEG shows low amplitude, high frequency beta waves

•Heart rate and blood pressure increases

•Breathing is quicker and more irregular

•Although occasional twitching occurs, the muscles in the face and body are limp

•Paradoxical sleep (internally the brain and body are active, while, externally, the body appears inactive)

CHARACTERISTICS & PATTERNS OF SLEEPREM SLEEP

REM SLEEP CHARACTERISTICS

•80% of time that someone is awoken during REM sleep that person will report that they were dreaming

READ BOX 3.4 – WHY WE DREAM (pg.142-143)

HOMEWORK

LEARNING ACTIVITY 3.2 (pg.143)LEARNING ACTIVITY 3.3 (pg.144)

CHANGES IN SLEEP PATTERNS OVER THE LIFESPAN

CHANGES IN SLEEP PATTERNS OVER THE LIFESPAN

CHANGES IN SLEEP PATTERNS OVER THE LIFESPANSLEEP-WAKE CYCLE SHIFT DURING ADOLESCENCE

CIRCADIAN RHYTHM

Hormones are produced in a 24-hour period to control body functions

MELATONIN is the neurotransmitter released that causes us to feel sleepy. This cycle is linked to external cues such as

sunlight, alarm clocks, meal times & television

CHANGES IN SLEEP PATTERNS OVER THE LIFESPANSLEEP-WAKE CYCLE SHIFT DURING ADOLESCENCE

CIRCADIAN RHYTHMHormones are produced in a 24-hour period to control body functions

SLEEP-WAKE CYCLE SHIFTA hormonally induced shift of the body clock forward by about 1 to 2 hoursThis means an adolescent is sleepier 1 to 2 hours late than other people

RESULTS IN SLEEP DEBTSleep that is owed and needs to be made up

(Now you know why you sleep in on the weekend!!)

HOMEWORK

LEARNING ACTIVITY 3.5 (pg.152)LEARNING ACTIVITY 3.6 (pg.152)