Chapter 10

Question 1

Circadian Rhythm

Answer 1

Pattern of behavioral, biochemical, or physiological fluctuation that has a 24-hour period.

Question 2

Ultradian

Answer 2

Period shorter than a day, usually several minutes to several hours long

Question 3

Infradian

Answer 3

Period longer than a day

Question 4

Free-running

Answer 4

Rhythm of behavior shown by an animal deprived of external cues about time of day

Question 5

Period

Answer 5

Interval between two similar points of successive cycles, such as sunset to sunset

Question 6

Phase Shift

Answer 6

Shift in the activity of a biological rhythm, typically provided by a synchronizing environmental stimulus

Question 7

Entrainment

Answer 7

The process of synchronizing environmental stimulus

Question 8

Zeitgeber

Answer 8

“time-giver” The stimulus (usually the light-dark cycle) that entrains circadian rhythms

Question 9

Suprachiasmatic Nucleus (SCN)

Answer 9

Small region of hypothalamus above the optic chiasm that is the location of a circadian clock.

Question 10

Melatonin

Answer 10

Amine hormone that is secreted by the pineal gland at night, signaling day length to the brain.

Question 11

Retinohypothalamic pathway

Answer 11

The route by which retinal ganglion cells that project to the suprachiasmatic nucleus

Question 12

Melanopsin

Answer 12

Photopigment found in those retinal ganglion cells that project to the suprachiasmatic nucleus.

Question 13

Rapid-eye-movement (REM) sleep

Answer 13

“paradoxical sleep” Small-amplitude, fast EEG waves, no postural tension and rapid eye movements.

Question 14

non-REM sleep

Answer 14

3 stages,, defined by presence of distinctive EEG activity

Question 15

Desynchronized EEG

Answer 15

“beta activity” pattern of EEG comprised of a mix of many different high and low EEG’s

Question 16

Alpha Rhythm

Answer 16

Brain potential of 8-12 hertz, occurs during relaxed wakefulness

Question 17

Vertex Spike

Answer 17

Sharp-wave EEG pattern seen during stage 1 sleep

Question 18

Stage 1 Sleep

Answer 18

Initial stage of non-REM sleep, small amplitude EEG waves of irregular frequency, shlow heart rate, reduced muscle tension

Question 19

Stage 2 Sleep

Answer 19

Bursts of regular 14-18 hertz EEG waves called sleep spindles

Question 20

Sleep Spindle

Answer 20

14-18 Hz EEG waves (characteristic to stage 2)

Question 21

K complex

Answer 21

Sharp negative EEG potential seen in sleep stage 2

Question 22

Stage 3 Sleep

Answer 22

“slow wave sleep” (SWS) Stage of non-REM sleep defined by presence of large amplitude, show delta waves

Question 23

Delta Wave

Answer 23

Slowest type of EEG wave. (characteristic to stage 3)

Question 24

Nightmare

Answer 24

Long, frightening dream that awakens sleeper from REM sleep

Question 25

Night Terror

Answer 25

Sudden arousal from stage 3 sleep, marked by intense fear and autonomic activation