methods

Question 1

what are some objective methods of observing sleep?

Answer 1

actigraphy, brain imagery, depth electrodes, polysomnography

Question 2

actigraphy

Answer 2

accelerometer - tells you how much you move (based on idea that if you’re not moving, you’re probably sleeping)

Question 3

functional near infrared spectroscopy

Answer 3

similar to mri and eeg but less invasive - measures hemoglobin concentration and absorption of near infrared light

Question 4

depth electrodes

Answer 4

yucky wires implanted into head for lots of days (not experimental! Meant for pre operative/diagnostic epilepsy non responsive to medication - basically only for treatment things - we just learn about sleep from these patients because the wires stay in their heads during both sleep and waking)

Question 5

polysomnography

Answer 5

the gold standard in sleep research - eeg (brain), eog (eyes), emg(muscles), ekg (heartrate) - bunch of sensors on face

Question 6

what does EEG measure?

Answer 6

sleep stages, sleep onset, anomalities

Question 7

EOG

Answer 7

REM - eye movements: REM sleep and slow rolling eye movements in SWS

Question 8

EMG

Answer 8

teeth grinding, restless leg, etc - muscle tonus - atonia characteristic of REM, body movement during sleep, and sleep disorders

Question 9

EKG

Answer 9

heart conditions

Question 10

what is the last part of the body to relax in sleep?

Answer 10

the face

Question 11

what is bruxism?

Answer 11

teeth grinding

Question 12

what are the sleep stages

Answer 12

nrem1, nrem 2, nrem3 (used to be stage 3 and 4), rem

Question 13

nrem 1

Answer 13

• Sleep onset
  
  • Hynogogic images
  • Rolling eyes
  • Diminished responsiveness
    Sleepiness felt before onset

Question 14

nrem 2

Answer 14

• Mixed freq, low ampp
  
  • K complex: bipolar wave (like slow wave 0-2 Hz, lasts .5 sec) that happens when the brain notices something in the outside world but decides to preserve sleep (thalamocortical gating) - also plays a role in memory consolidation
    Sleep spindle: associated with protective processes against neurodegeneration and with brain plasticity - studies try to stimulate sleep spindles in old people for their neuroprotective effects

Question 15

nrem 3

Answer 15

• Slow wave sleep/Delta 0-4hz
  
  • Characterized by a predominance of delta activity - slow and synchronized
  • Parasomnias, night terrors, sleep walking
  • Dont want to wake up from slow wave - will be groggy, cranky, headachey (i.e. only take a 20 minute nap or a 90 minute nap (then you cycle back))

Question 16

REM

Answer 16

• Rapid eye movements
  
  • Mixed frequencies
  • Atonia
  • Breathing and cardiac activity irregular
    Dreamings, nightmares, realistic and engaging mental activity

Question 17

k complexes

Answer 17

· Pattern with a sharp high amplitude spike, followed by a slower positive wave
· Present during stage 2 of NREM sleep
· Supposed to help the brain filter out irrelevant stimuli
· When the brain notices something disruptive, the brain responds with a K complex - maybe serving to inhibit further processing of the stimulus?
Brains mechanism for maintaining undisturbed sleep

Question 18

sleep spindles

Answer 18

· Bursts of rhythmic activity (freq range: 11-16Hz)
· Seen in central regions of the brain like the thalamas
· Role in information processing and memory consolidation during sleep
· Enhance memory and cognitive functions? Learning and problem solving?
Younger people have more sleep spindles