Chapter14 Flashcards
Electroencephalogram (EEG)
A measure of the gross electrical activity of the brain, commonly recorded through scalp electrodes.
Electrooculogram (EOG)
A measure of eye movement.
Electromyogram (EMG)
A measure of the electrical activity of muscles.
Alpha waves
Regular, 8-to-12-per-second, high amplitude EEG waves that typically occur during relaxed wakefulness and just before falling asleep.
Delta waves
The largest and slowest EEG waves.
Initial stage 1 EEG
The period of the stage 1 EEG that occurs at the onset of sleep; it is not associated with REM.
Emergent stage 1 EEG
All periods of stage 1 sleep EEG except initial stage 1; each is associated with REMs.
REM sleep
The stage of sleep characterized by rapid eye movements, loss of core muscle tone, and emergent stage 1 EEG.
Slow-wave sleep (SWS)
Stage 3 and 4 of sleep, which are characterized by the largest and slowest EEG waves.
Activation-synthesis theory
The theory that dream content reflects the cerebral cortex’s inherent tendency to make sense of, and give form to, the random signals it receives from the brain stem during REM sleep.
Recuperation theories of sleep
Theories based on the premise that being awake disrupts the body’s homeostasis and the function of sleep is to restore it.
Adaptation theories of sleep
Theories of sleep based on the premise that sleep evolved to protect organisms from predation and accidents and to conserve their energy, rather that to fulfill some particular physiological need.
Executive function
A collection of cognitive abilities (planning, insightful thinking, and reflective memory) that appear to depend on the prefrontal cortex.
Microsleeps
Brief periods of sleep that occur in sleep-deprived subjects while they remain sitting or standing.
Carousel apparatus
An apparatus used to study the effects of sleep depravation in laboratory rats.
Circadian rhythms
Diurnal (daily) cycles of body functions
Zeitgebers
Environmental cues, such as light-dark cycles, that entrain the circadian rhythms.
Free-running rhythms
Circadian rhythms that do not depend on environmental cues to keep them on a regular schedule.
Free-running period
The duration of one cycle of a free-running rhythm.
Internal desynchronization
The cycling on different schedules of the free-running circadian rhythms of two different processes.
Jet lag
The adverse effects on body function of the acceleration of zeitgeber during east-bound flights or their deceleration during west-bound flights.
Circadian clock
An internal timing mechanism that is capable of maintaining daily cycles of physiological functions, even when there are no temporal cues from the environment.
Suprachiasmatic nuclei (SCN)
Nuclei of the medial hypothalamus that control the circadian cycles of various body functions.
Melanopsin
Photopigment found in retinal cells that respond to changes in background illumination and play a role in synchronizing circadian rhythms.
