Consciousness Flashcards
Purpose of consciousness?
What does it do?
- Monitor mental events
- Regulate thought and behaviour
What is it for?
- Consciousness may have evolved to direct or control behaviour in an adaptive
way
Altered States of Consciousness
SLEEP, MOTIVATION, HYPNOSIS, RELIGIOUS EXPERIENCES
These are states in which the usual conscious ways of perceiving, thinking and feeling are modified or disrupted.
Location of consciousness
- Hindbrain + Midbrain ; arousal and sleep
- Damage to the reticular formation can lead to coma
- Prefrontal cortex is key for conscious control of information processing
Psychodynamic view of consciousness - Freud
UNCONSCIOUS - mental events that are inaccessible to awareness - events that are actively kept out of awareness
CONSCIOUS - mental events of which you are aware
PRECONSCIOUS - mental events that can be brought into awareness
SLEEP- Functions of sleep?
- memory consolidation
- energy conservation
- restoring bodily functions
Sleep deprivation can cause?
- altered immune function
- early death
- hallucinations
- perceptual disorders
Why do we sleep:
Conservation hypothesis?
Restorative Hypothesis?
REM Necessary for?
Conservation hypothesis?
NREM sleep evolved to conserve organisms’ energy when not searching for food etc
Restorative Hypothesis?
Brain works hard during waking states and subsequently sustain cell damage; NREM repairs that damage
REM Necessary for?
Normal development of visual, other sensory and motor systems in intimacy. Learning and memory in adults
What are CIRCADIAN RYTHMS?
- Cyclical biological process that evolved around daily cycle of light and dark (awake and sleep)
- foetuses begin to show rhythms by 6 months gestation
- circadian rhythms account for difficulties people experience with time zones + night shift
Differences in CIRCADIAN RYTHMS?
- daily rhythms occur in all individuals, but exact timing differs from person to person ; CHRONOTYPES
- Different chronotypes = different patterns of sleep and wake
- Morning type = early to bed, early to rise
- Evening type = late to bed, late to rise
States of Sleep
NREM (Non REM sleep)
- stages 1,2,3,4
- phases of sleep with no rapid eye movements
- helps us recover from daily fatigue
- 75% to 80% total sleep time
States of Sleep
REM (Rapid Eye Movement Sleep)
- light, associated with dreaming
- body still, motor paralysis (except for diaphragm)
- 20% to 25% total sleep time
Sleep Research Instruments
- EEG Electroencephalograph = measure brain electrical activity
- EMG Electromyograph = measure muscle activity
- EOG Electrooculograph = measure eye movements
Changes in sleep patterns during stages of life?
- Newborn infants sleep up to 16 hours a day - 50% NREM + 50% REM
- Young adults sleep 7-8 hours a day - 75% NREM + 25% REM
- By age 50, sleep 6 hours a day - 75% NREM + 25% REM
SLEEP STAGE 1
- 3-7 CPS (cycles per second)
- Theta waves
- Slow eye movements
- Muscles relax
- BP drops
SLEEP STAGE 2
- 12-14 CPS
- K complex = high amplitude waves
- Sleep spindles = low amp bursts activity
