Biological Rhythms and Sleep Continued

Question 1

the pattern of activity in an … contains many frequencies: mixture of low amplitude waves with many fast frequencies (>15-20 Hz)

• known as beta activity or desynchronized EEG
• The relaxed mind exhibits an alpha rhythm, a regular oscillation at a frequency of 8-12 Hz

Answer 1

awake, alert person

Question 2

• time spent in alpha rhythm decreases
• waves of smaller amplitude and irregular frequency begin
• vertex spikes or sharp waves appear
• heart rate slows, muscles relax, eyes roll about slowly
• lasts several minutes

Answer 2

stage 1 sleep

Question 3

• sleep spindles - bursts of 12-14 Hz waves
• K complexes - sharp negative EEG potentials

delta waves- large amplitude, very slow waves; about one per second

Answer 3

Stage 2 sleep

Stage 3 sleep

Question 4

small amplitude, high frequency activity, like an awake person

• eyes dart rapidly under closed lids
• breathing and heart rate are irregular, like when awake
• called paradoxical sleep because of active brain waves but complete absence of muscle tone (Atonia)

Answer 4

REM sleep

Question 5

• total sleep time ranges from 7-8 hours
• about half is stage 2 sleep
• about 20% is REM sleep
• cycles lasts 90-110 minutes
• cycles early in the night have more stage 3 SWS
• later cycles have more REM sleep

Answer 5

typical night of a young adult sleep

Question 6

occur during REM sleep, characterized by: visual imagery, sounds, smells, emotions

• sense the dreamer is “there”

Answer 6

vivid dreams

Question 7

are long, frightening dreams that awaken the sleeper from REM sleep

Answer 7

nightmares

Question 8

sudden arousals from stage 3 SWS, marked by fear and autonomic nervous system activity

Answer 8

night terrors

Question 9

humans sleep more during infancy than in adulthood, but sleep increases during

• this suggests that the functions of sleep are more important at different stages of life

Answer 9

adolescences

Question 10

• shorter sleep cycles
• more REM sleep- 50% which may provide essential stimulation to the developing nervous system
• stable patterns of sleep at night don’t tend to appear until about 16 weeks

Answer 10

infant sleep

Question 11

partial or total:

• increased irritability
• difficulty concentrating
• episodes of disorientation

Answer 11

sleep deprivation

Question 12

sleeping more than usual after a period of deprivation

night 1- stage 3 sleep shows greatest increase relative to normal, at the expense of stage 2 sleep

nights 1 and 2- REM sleep shows a great increase relative to normal; its also more intense than normal, with more rapid eye movements

Answer 12

sleep recovery

Question 13

sleep conserves … muscular tension, heart rate, blood pressure, temp and rate of respiration are reduced

Answer 13

energy!

Question 14

sleep forces species to conform to the … to which they are adapted

• sleep helps animals avoid predators, animals sleep during the part of the day when they are most vulnerable

Answer 14

ecological niche

Question 15

sleep has a …. materials used up during waking hours, such as proteins, are rebuilt or restored

• most growth hormone is only released during SWS
• proper sleep is essential for immune function

Answer 15

restorative function

Question 16

sleep may aid … sleep during the interval between learning and recall improves retention

• learning of perceptual skills is improved by a period of REM sleep
• consolidation of declarative memory tasks and complicated motor skills seems to benefit from SWS
• REM sleep is not absolutely necessary for learning

Answer 16

memory consolidation

Question 17

• a forebrain system: generates SWS
• brainstem system: activates the forebrain to wakefulness
• a pontine system: triggers REM sleep
• a hypothalamic system: coordinates the other 3

Answer 17

sleep is an active state mediated by