Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
14 Cards in this Set
- Front
- Back
What photoreceptors are responsible for intake of light and regulation of biological clock?
|
Melanopsin receptors transmit sernsory information via retinohypothalamic tract to the SCN (suprachiasmic nucleus)
|
|
What is the MASTER BIOLOGICAL CLOCK?
|
SCN is the main clock. It coordinates the circadian clocks all over the body.
SCN drives the circadian drive for wakefulness! |
|
What are two main hormones that SCN controls.
|
Melatonin and cortisol. Both oscillate.
Melatonin levels are HIGH at NIGHT Cortisol levels are OPPOSITE. STRESS INCREASES DURING DAY. |
|
What are the two factors determining performance and alertness?
|
Circadian drive for wakefulness (via SCN) and the homeostatic need for sleep (starts when you wake up and gets extreme by 16hrs)
|
|
When does sleep-walking occur?
|
Delta sleep: NREM 3&4...earlier hours of the evening. very HIGH amplitude.
REM cycles become more frequent later in the night. |
|
How long is one sleep cycle?
|
~90-120 minutes. This is considered normal architecture
|
|
What kinds of deficits do we see in sleep loss?
|
Cognitive (LAPSES ARE HALLMARK!), physiological (EYES ROLL OUT AND UP...SLOW BLINKING), behavorial (PFC hypometabolism, inferior parietal, occipital, thalamus)
Other physiologic changes...elevated cortisol levels (HPA activation). elevated insulin resistance. leukocytosis/monocytosis INCREASED OBESITY AND MORTALITY. Working memory declines. |
|
True/false?
Environmental factors cause sleepiness? |
FALSE, all they do is UNMASK an underlying situation.
|
|
Must sleep debt paid off?
|
YES! not necessarily the same number of hours, but a certain type of sleep.
With effort, people can improve their task performance, but OPTIMACY AND CONSISTENCY ARE LOST IN SLEEP DEPRIVATION. |
|
What is sleep inertia?
|
A feeling of groggyness, hung over feeling. Can last for 15-30 minutes upon waking.
|
|
What are two KEY components involved in good night's sleep.
|
1) Number of hours
2) Normal sleep architecture (normal REM cycles) |
|
Which is worse? ACUTE sleep deprivation or CHRONIC sleep deprivation?
|
CHRONIC AND ACUTE = Just as bad!
Levels of increased depression, problems at work |
|
Do people know how sleepy they really are? How good they are at cognitive tasks?
|
Vulnerable people to sleep loss DO NOT PERCEIVE DIFFERENCES IN THEIR ABILITY TO PERFORM TASKS
|
|
What are big risks for driving and getting in accidents?
|
NIGHTSHIFT (8 AM accidents), young male drivers, commercial truck drivers, patients with sleeping disorders.
|