Consciousness and sleep Flashcards
(36 cards)
Evolutionary (circadian) theory
Emphasises the relationship of sleep to circadian rhythms. The idea that sleep is adaptive and evolved to enhance survival.
Pros: Accounts for why and when we sleep
Con: Does not account for loss of awareness and alertness during sleep
Restoration theory
Sleep is to recover from depleting activities during wake up time that use up the body’s physical and mental resources.
NREM: restores and repairs body (growth and tissue repair)
REM: Restores body and is involved in learning and memory (the consolidation of memory)
REM REBOUND
catching up on REM sleep immediately following a period of lost REM sleep by spending longer in REM sleep than usual next time sleeping.
Pros: Research evidence
Cons: A physically disabled person confined to their bed has a similar sleep cycle to a physically active individual
Automatic process
Requires little conscious awareness and mental effort, minimal attention and does not interfere with the performance of other activities
Beta brainwaves
High frequency, low amplitude
- Alertness and intensive mental activity during NWC
- Present during states of tension, anxiety, threat and fear
Delta brainwaves
Low frequency, high amplitude
- Deep, dreamless sleep or unconsciousness
- Begin to appear in stage 3 of NREM sleep
- Stage 4 - deepest sleep
Theta brainwaves
Med frequency, mix of medium, high, and low amplitude
- Very drowsy, falling asleep, just waking
- Awake and engaged in creative activities, excited and deeply meditating
Controlled processes
Conscious, alert awareness and mental effort in which the individual focuses their attention on achieving a particular goal
Alpha brainwaves
Low to medium frequency, low to medium amplitude
- Awake and alert but mentally and physically relaxed and internally focused
- Drowsy or relaxed state, just prior to falling asleep
Selective attention
Choosing and attending to a specific stimulus to the exclusion of others
Daydreaming as an altered state of consciousness
A temporary change in one’s normal state
A temporary shift on the consciousness continuum
Divided attention
Ability to distribute our attention and undertake two or more activities simultaneously
EOG
Electro-occulargraph
Measures eye movement by detecting, amplifies and recording electrical activity in eye muscles that control eye movements
EMG
Electromyograph
Detects, amplifies and records the electrical activity of muscles
EEG
Electroencepholograph
Detects, amplifies and records patterns of electrical activity in the brain
Circadian rhythm
Changes in bodily functions and activities during a cycle of 24 hours
Area of the hypothalamus - the suprachiasmatic nucleus - is called the ‘master’ biological clock. It regulates timing and activity of the sleep wake cycle.
The brain induces sleep by alerting the pituitary gland to secrete melatonin until exposed to light stimulus
Ultradian rhythm
Changes in bodily functions and activities during a cycle of less than 24 hours
Psychological construct
Cannot be directly observed eg) consciousness
Self reports
Written or spoken responses to questions, statements or instructions
Sleep diary
A self recorded report of an individuals sleep and waking time activities
Video monitoring
Recording of externally observable physiological responses during a sleep episode
Methods to study consciousness
EEG, EMG, EOG, self reports, sleep diaries, video monitoring
Infant’s sleep
Sleep duration = irregular
Fewer sleep cycles but cyclic alternation of NREM-REM sleep is present
REM sleep = restless, may contain movement
Sleep onset occurs through REM
Proportion of REM sleep is relatively high
Young children
Total sleep time decreases as kid gets older
REM sleep decreases, NREM increases
Slow wave deep sleep is quantitatively and qualitatively different from adults
Adolescents
Total sleep time decreases, REM sleep too
NREM = 3 +4 stages decline and 2 increases
Slow wave deep sleep decreases more
