Notes on Module 4
4.1
● Consciousness describes our awareness of internal and external stimuli.
-Many other states of consciousness people experience, daydreaming, intoxication, and
unconsciousness due to anesthesia.
● Sleep is a state marked by relatively low levels of physical activity and reduced
sensory awareness that is distinct from periods of rest that occur during
wakefulness.
● Wakefulness is characterized by high levels of sensory awareness, thought, and
behavior.
Biological Rhythms
● Biological rhythms are internal rhythms of biological activity.
-A woman’s menstrual cycle is an example of a biological rhythm—a recurring, cyclical
pattern of bodily changes.
● One complete menstrual cycle takes about 28 days a lunar month but many
biological cycles are much shorter.
● A circadian rhythm is a biological rhythm that takes place over a period of about
24 hours.
● Homeostasis is the tendency to maintain a balance, or optimal level, within a
biological system.
● The brain’s clock mechanism is located in an area of the hypothalamus known as
the suprachiasmatic nucleus (SCN).
, ● One important regulator of sleep-wake cycles is the hormone melatonin.
-Melatonin release is stimulated by darkness and inhibited by light.
● The pineal gland, an endocrine structure located inside the brain that releases
melatonin, is thought to be involved in the regulation of various biological rhythms
and of the immune system during sleep
● Sleep regulation refers to the brain’s control of switching between sleep and
wakefulness as well as coordinating this cycle with the outside world.
Disruptions of Normal Sleep
● Jet lag is a collection of symptoms that results from the mismatch between our
internal circadian cycles and our environment.
, -These symptoms include fatigue, sluggishness, irritability, and insomnia(i.e., a
consistent difficulty in falling or staying asleep for at least three nights a week over a
month’s time)
● Rotating shift work refers to a work schedule that changes from early to late on
a daily or weekly basis.
● A person with a sleep debt does not get sufficient sleep on a chronic basis.
-The consequences of sleep debt include decreased levels of alertness and mental
efficiency.
4.1
● Consciousness describes our awareness of internal and external stimuli.
-Many other states of consciousness people experience, daydreaming, intoxication, and
unconsciousness due to anesthesia.
● Sleep is a state marked by relatively low levels of physical activity and reduced
sensory awareness that is distinct from periods of rest that occur during
wakefulness.
● Wakefulness is characterized by high levels of sensory awareness, thought, and
behavior.
Biological Rhythms
● Biological rhythms are internal rhythms of biological activity.
-A woman’s menstrual cycle is an example of a biological rhythm—a recurring, cyclical
pattern of bodily changes.
● One complete menstrual cycle takes about 28 days a lunar month but many
biological cycles are much shorter.
● A circadian rhythm is a biological rhythm that takes place over a period of about
24 hours.
● Homeostasis is the tendency to maintain a balance, or optimal level, within a
biological system.
● The brain’s clock mechanism is located in an area of the hypothalamus known as
the suprachiasmatic nucleus (SCN).
, ● One important regulator of sleep-wake cycles is the hormone melatonin.
-Melatonin release is stimulated by darkness and inhibited by light.
● The pineal gland, an endocrine structure located inside the brain that releases
melatonin, is thought to be involved in the regulation of various biological rhythms
and of the immune system during sleep
● Sleep regulation refers to the brain’s control of switching between sleep and
wakefulness as well as coordinating this cycle with the outside world.
Disruptions of Normal Sleep
● Jet lag is a collection of symptoms that results from the mismatch between our
internal circadian cycles and our environment.
, -These symptoms include fatigue, sluggishness, irritability, and insomnia(i.e., a
consistent difficulty in falling or staying asleep for at least three nights a week over a
month’s time)
● Rotating shift work refers to a work schedule that changes from early to late on
a daily or weekly basis.
● A person with a sleep debt does not get sufficient sleep on a chronic basis.
-The consequences of sleep debt include decreased levels of alertness and mental
efficiency.
