Chapter 4 - States of Consciousness Flashcards
consciousness
our awareness of internal (e.g. hunger) and external stimuli (e.g. sunlight)
sleep
- a state marked by relatively low levels of physical activity and reduced sensory awareness
- distinct from periods of rest that occur during wakefulness
wakefulness
characterized by high levels of sensory awareness, thought, and behavior
biological ryhthms
- a recurring, cyclical pattern of bodily changes
- ex. periods, body temperature
circadian rhythm
- a biological rhythm that takes place over a period of about 24 hours
- body’s internal “clock”
homeostasis
- the tendency to maintain a balance, or optimal level, within a biological system
- the hypothalamus is a main center of homeostasis
suprachiasmatic nucleus (SCN)
- where the brain’s clock mechanism is
- light-sensitive neurons in the retina provide information to the SCN based on the amount of light present - allows internal clock to be in sync w/outside world
melatonin
- hormone that’s a regular of sleep-wake cycles
pineal gland
- endocrine structure located inside the brain that releases melatonin
- thought to be involved in the regulation of various biological rhythms and immune system in sleep
sleep regulation
- to the brain’s control of switching between sleep and wakefulness as well as coordinating this cycle with the outside world
jet lag
a collection of symptoms that results from the mismatch between our internal circadian cycles and our environment
insomnia
a consistent difficulty in falling or staying asleep for at least three nights a week over a month’s time
rotating shift work
- a work schedule that changes from early to late on a daily or weekly basis
- schedule changes so much it’s hard for circadian rhythm to maintain
sleep debt
someone that doesn’t get good sleep on a chronic basis
meta-analysis
a study that combines the results of many related studies
sleep rebound
the fact that a sleep-deprived individual will fall asleep more quickly during subsequent opportunities for sleep
evolutionary psychology
discipline that studies how universal patterns of behavior and cognitive processes have evolved over time as a result of natural selection
beta waves
- the most popular brain activity while awake
- have highest frequency and lowest amplitude
rapid eye movement (REM)
- characterized by darting movements of the eyes under closed eyelids
- appear very similar to brain waves during wakefulness
- last stage of sleep cycle
non-REM (NREM)
- first three stages of sleep
- stages divided by three patterns of brain waves
stage 1 sleep
- a transitional phase that occurs between wakefulness and sleep
- heart rate and breathing slow down
- easy to be woken up
alpha waves
- brain waves during stage 1 sleep
- patterns of waves resemble that of someone who is very relaxed, yet awake, have less variability
theta waves
- brain waves during stage 1 sleep
- lower waves and higher amplitude than alpha waves
stage 2 sleep
- body goes into a state of deep relaxation
- Theta waves still dominate brain activity, but are interrupted by brief bursts of activity known as sleep spindles
sleep spindle
- happen during stage 2
- a rapid burst of higher frequency brain waves that may be important for learning and memory