Chapter 5 Psych

General Psychology - Chapter 5: Consciousness

Consciousness

Subjective experience of world & ourselves (i.e. our bodies & mental perspectives)

Diff states of consciousness

Awake vs sleep vs in between

Consciousness is sensitive to brain chem (meds alter!), expectations, culture

Biology of Sleep

Circadian rhythms: cyclical processes that occur on ~24 hr basis

E.g. hormone release, brain waves, body temp, drowsiness

Biological clock: term that describes part of hypothalamus that controls sleep/awake cycles

Releases melatonin

Infl by external stimuli

Disruptions can be harmful (jet lag, night shifts, etc)

Sleep we need decreases w age

Newborns: ~16 hrs

>65: ~7-8 hrs

College students: ~9 hrs

Rarely < 6 hrs (due to DEC2 mutation which

Consequences of inadequate sleep

Physiological – weight gain, depression, decreased immune sys activity

Cognitive – difficulty learning, slower rxn times, trouble problem solving

Lack of sleep 1 night is not a big deal

Building up a sleep debt is a big deal

You can’t catch up w sleep on weekends

Stages of Sleep

Rapid eye movement (REM): movement of eyes underneath eyelids during sleep, associated with vivid dreams

non-REM (NREM) sleep: stages 1-4 of sleep cycle where rapid eye movement doesn’t occur and dreaming is less frequent & vivid

Cycle through 5 stages of sleep in 90-min cycles

Stages 1-4 (Non-REM or NREM) → fewer dreams

(REM) sleep AKA Stage 5 → vivid dreams

Brain Waves

EEG scan allows us to read brain waves (esp for ppl who get strokes in sleep)

Beta waves: v rapid & narrow; take place when we’re awake

Alpha waves: lower frequency than β-waves & take place in calm wakefulness

E.g. when our eyes are close but we aren’t sleeping

Theta waves: produced during drowsiness and light sleep

Delta waves: slower & wider; take place at deepest level of NREM sleep

KNOW THE Names, association, def’n for these waves & what they look like

Stages of Sleep

Stage 1 (5-10 min/cycle)

Barely asleep

Theta waves

Hypnagogic imagery: dream-like images that flow in and out of consciousness

Myoclonic jerks: sudden jerks in our limbs as if we were startled

Stage 2 (10-30 min/cycle)

Theta waves

Sleep spindles (left on image): sudden intense bursts of electrical activity

K-complexes (right on image): sharply rising & falling waves, only appear when we’re asleep)

HR slows, Body Temp decreases, Muscles relax

Spend 65% of sleep in stage 2

Stage 3 & 4 (15-30 min/cycle)

Delta waves

Deep sleep

Adults spend 25% of their sleep in deep sleep

Stage 5 (REM sleep; 10-20 min/cycle)

Brain activity similar to wakefulness (AKA alpha & beta waves)

Unique brainwave

Increase HR & BP

Longer as night goes on

20-25% of sleep

After 10-20 mins of REM sleep, repeat cycle

We circle back to REM sleep 5-6 times each night

Dreams and Sleep

Are dreams tend to be more negative/aggressive/about misfortune than positive

NREM dreams

Shorter & fewer dreams

More thought-like

Repetitive

Concerned w/ daily tasks

Generally less frequent

REM dreams

More dreams

Emotional, illogical

Prone to plot shifts

Biologically crucial

Refers to rat study where rats died bc they didn’t experience REM sleep w/in a few weeks

REM Sleep

REM Behavior Disorder: rare disorder where brain stem structures usually prevent movement during REM sleep

A person may attempt to act out their REM dreams w/o necessarily being aware that they are doing son

REM rebound: over-activity after REM deprivation leading to intense dreams or nightmares