biological rhythms and sleep

Question 1

biological rhythms

Answer 1

inherent rhythm that controls or initiates various biological processes

Question 2

period

Answer 2

time required to complete a cycle of activity

Question 3

circannual rhythm

Answer 3

Yearly (e.g., migratory cycles of birds)

Question 4

infradian rhythm

Answer 4

Less than a year (e.g. human menstrual cycle)

Question 5

circadian rhythm

Answer 5

Daily (e.g. human sleep-wake cycle)

Question 6

ultradian rhythm

Answer 6

Less than a day (e.g. eating cycle)

Question 7

endogenous rhythms

Answer 7

Control is within the animal, not stimulus-driven (i.e. exogenous)
Neural system that times behaviour
Allows animals to anticipate events (ex: sunrise) before they happen

Question 8

free-running rhythms

Answer 8

Remove all external cues: no changes in light, no food schedule, no clocks, no alarms, no phone, etc

Question 9

nocturnal animals

Answer 9

those that are chiefly awake at night (rodents)
If left in constant darkness: awake-sleep period is <24 hours
If left in constant light: awake-sleep period is >24 hours

Question 10

diurnal animals

Answer 10

those that are mostly awake during the day, sleep at night
If left in constant darkness: awake-sleep period is >24 hours
If left in constant light: awake-sleep period is <24 hours

Question 11

entrainment

Answer 11

determination or modification of the period of a biorhythm
Our biological clock is entrained by light
Blind individuals and sailors serving on submarines may experience sleep problems

Question 12

Zeitgeber “time giver”

Answer 12

environmental event that entrains biological rhythms
Light resets the biological clock; social interactions (yawning)

Question 13

shift work

Answer 13

drastic changes in work schedule (ex: working morning shift to working graveyard shift) is more stressful than subtle changes (evening shift to graveyard shift)

Question 14

jet lag

Answer 14

changing time zones: eastward travel- Lose time, difficult to adjust
Westward travel- gain time, easier to adjust

Question 15

Suprachiasmatic Nucleus

Answer 15

Chief pacemaker of circadian rhythms
Located just above (“supra”, dorsal to) the optic chiasm, in the hypothalamus

Question 16

retinopothalamic pathway

Answer 16

Originate from set of photoreceptors in the retina, called cryptochromes
Melanopsin- photopigment
Provides light information to the SCN
Entrains the rhythmic activity of the SCN

Question 17

why does the oscillator oscillate

Answer 17

Is the endogenous rhythm of the SCN a result of nature (genetic factors) or nurture (learned)?
In absence of Zeitgebers, there is still rhythmiccity to an animals behaviour
An animals behaviour will remain rhythmic even if previous generations are not exposed to Zeitgebers
If the SCN is lesioned in a mother rat, so that her own behaviour lacks rhymicity her (normal) offspring will still demonstrate biological rhythms

Question 18

beta rhythm

Answer 18

Fast brain-wave activity (15 to 30 Hz) pattern associated with a waking EEG

Question 19

theta rhythm

Answer 19

Large brain waves (4 to 7Hz) associated with drowsiness (stage 1)

Question 19

alpha rhythm

Answer 19

Large, extremely regular brain waves (7 to 11 Hz) associated with relaxation/drowsiness

Question 20

delta rhytm

Answer 20

Slow brain-wave activity (1 to 3Hz) pattern associated with deep sleep (also known as slow wave sleep

Question 21

REM sleep

Answer 21

Fast brain-wave pattern displayed by the neocortical EEG record during sleep;

Question 22

stages of sleep

Answer 22

Stage 1: low voltage, fast activity
Stage 2: K complexes and sleep spindles
SWS- Stage 3/ Stage 4: delta waves
Emergent stage 1 EEG: REM or paridoxal sleep
90 minute cycles

Question 23

Non-REM

Answer 23

Body movements (toss and turn), decline in body temperature, heart rate decreases, blood flow increases
Some dreaming, but different (less vivid) from REM
Sleepwalking, sleeptalking, and night terrors happen in NREM

Question 24

REM

Answer 24

Eye movements dart around rapidly (in other stages, eyes roll slowly)
Atonia- seen in the EMG: absence of muscle tone due to the inhibition of motor neurons
Sleep paralysis
Dreams are quite vivid
Stickgold and the Tetris experiment

Question 25

freud

Answer 25

dreams symbolize unfulfilled and unconsious wishes
Manifest content: bizarre events in the dream
Latent content: “true” meaning of the dream

Question 26

jung

Answer 26

personal and collective unconsious
Common themes in dreams reflect the “collective unconsious” (history of the human species)
How do we empirically determine which is right?

Question 27

J ALLan hobson

Answer 27

Dreams are personal, but they have no meaning
The cortex, receiving signals from the brainstem, generates random images from memory stores