Exam 4 Flashcards
Biorhythm
Cyclical changes in behavior or bodily functions
Zeitgeber
a clock-setting cue
Entrainment
when a biorhythm is reset by a zeitgeber
Free-running rhythm
cycle that has a period of the body’s own devising
Jet lag
disruption of the body’s circadian phase
Circannual
yearly biorhythm (ex: migratory cycle of birds)
Circadian
daily biorhythm (ex: human sleep-wake cycle)
Ultradian
less than a day biorhythm (ex: human eating cycles)
Infradian
more than a day biorhythm (ex: human menstrual cycle)
Suprachiasmatic nucleus
master biological clock, mostly responsible for maintaining Circadian rhythms
Where is Suprachiasmatic nucleus located and what larger structure is it a part of?
It is located in the Hypothalmus and is part of the retinohypothalmic pathway
How do light signals (melanopsin photopigment signals) get from the retina to the SCN of the hypothalmus?
Light activates a special group of photoreceptors in the retina that send melanospin photopigment signals, via the retinal hypothalmic pathway (respond more slowly to light)
The pineal gland is an endocrine gland that produces the neurohormone melatonin at night.
In what situation mght taking a melatonin supplement be helpful?
Taking melatonin can help with insomnia. Taking it in the afternoon can phase-advance the biological clock, which can help relieve some jet lag.
What is the difference between advanced sleep phase disorder and delayed sleep phase disorder?
Advanced sleep phase disorder is when your rhythm makes you go to bed earlier while Delayed sleep phase disorder is when your rhythm you go to bed later
List interruptions of consciousness
Coma, vegetative state, minimally conscious state, and brain death
Coma
extended period of unsciousness caused by head trauma, stroke, or disease characterized by low brain activity that remains fairly steady
Vegetative state
person alternates between periods of sleep and moderate arousal but no awareness of surrounding
Minimally conscious state
one stage higher than a vegetative state marked by occassional brief periods of purposeful action and limited speech comprehension
Brain death
no sign of brain activity and no response to stimulus
Why do we sleep?
Conservation of energy, repair & restoration (release growth hormone to repair tissue), and learning & memory consolidation
Who sleeps more predator or prey?
Predatory animals sleep more than prey
When is human body temperature lowest during a 24-hour cycle?
Human termperature is lowest at 4:30 Am
What are growth hormones good for (besides growth) and when are they released during the 24-hour cycle?
Growth hormones are also good for regeneration of tissue, secreted during sleep
What tools do we use to measure that activity of the brain and body during sleep?
Polysomnograph
Electroencephalogram (EEG)
Electromyogram (EMG)
Electroculogram (EOG)
Polysomnograph
measure activity of brain & body
Electroencephalogram (EEG)
record brain wave activity
Electromyogram (EMG)
record muscle actvity
Electroculogram (EOG)
record eye movement
Stage 1 of sleep
Overall brain activity is high, but declining
Alpha rhythm: relaxation; brain waves of 8-12 Hz
Stage 2 of sleep
Sleep spindles & K-complexes
Sleep spindles
memory consolidation and declarative memories
K-complexes
sharp, high amp negative wave followed by slower positive wave; protect person from waking due to stimuli; lows of make up
Stage 3 & 4 of sleep
Slow wave sleep
Heart rate, breathing, brain activity slow with each stage
Percent of slow, high amp waves increases
What in particular occurs in stage 4 of sleep
thalmus stops relaying sensory info to cortex (unless extreme or relevant)
REM sleep stage
Paradoxical sleep
Considerable brain activity, HR, BP and breathing are more variable; more facial twitches
Postural muscles of bofy are most relaxed
REM seems to intensify dreams, but REM x=x dreaming
Which is stage of sleep is paradoxical sleep and why?
Rapid Eye Movement (REM) sleep is also known as paradoxical sleep because it is the lightest sleep, weirdest dreams, and paralyzed body.
Which neurotransmitters begin and end REM sleep?
Acetylcholine begins REM sleep
Seratonin ends REM sleep
Atonia
a lack of muscle tone
How does age affect sleep patterns?
Duration of REM sleep varies with age and changes dramatically over the life span. It is high in infancy, increased during growth spurts, in conjunction with physical exertion, and during pregnancy.
Developing brain needs lots of sleep.
As we age neurons in certain reticular nuclei tend to degenerate.
Normal rhythm of sleep becomes dysregulated (less orderly sleep patterns and less deep slow wave sleep from stage 3 & 4)
Insomnia is very common in older people
Insomnia
sleep disorder associated with inadequate sleep
Occurs in NREM
Caused by: noise, stress, pain medication, disorders like epilepsy or Parkinson’s disease, depression, anxiety, other psychatric conditions, dependence on sleeping pills, shifts in circadian rhythms
Sleep apnea
sleep disorder known for inability to breathe while sleeping for a prolonged period of time
Occurs during both REM and NREM?
Symptoms: sleepiness during day, impaired attention, depression, sometimes heart problems
Narcolepsy
sleep disorder characterized by frequent periods of sleepness
Occurs during NREM?
Symptoms: gradual or sudden sleepiness, occasional cataplexy, sleep paralysis, hypnagogic hallucinations
Cataplexy
muscle weakness triggered by strong emotions
Hypnagogic hallucinations
dreamlike experiences the persona has dfficulty distinguishing from reality
REM behavior disorder
vigorous movement during REM sleep
Acting out dreams (damage to pons)
Night terrors
experiences of intense anxiety from which a person awakens
During NREM
Sleep talking
occurs during both REM and NREM sleep
Sleep walking
runs in families, mostly in young children, and occurs mostly stage 3 & 4 of sleep (NREM)
Contrast sleep paralysis and sleep walking
Sleep paralysis is wakefulness while your motor system is still inhibited while Sleep walking is movement while your awareness is still inhibited
What are the effects of sleep deprivation (general, not specific peripheral effects)?
Cognitive deficits, poor reaction time, memory loss, mood imbalance, and hallucinations
Lack of sleep is secondarily deadily to humans (negative outcomes are deadily)
When do we dream?
Dream in both REM (real time, vivid dreams) and NREM (brief nightmares)
Learning
a change in an organism’s behavior as a result to experience
Memory
the ability to recall or recognize previous experience
Neuroplasticity
the nervous system’s potential for physical or chemical change, which engances its adaptibility
Associative learning
linkage of two or more unrelated stimuli to elicit a behavioral response
Classical conditioning
Pairing of 2 stimuli (conditioned stimuli + unconditioned stimuli = unconditioned response that turns conditioned)