Brain Rhythms/EEG/Sleep

Question 1

3.6 Behavioral States

Answer 1

Conscious: alert to drowsy
Sleep: NREM (EEG synchronized) and REM (desynchronized)
Unconscious: comatose and persistent vegetative

Question 2

Stupor

Answer 2

Partial or nearly completely unconscious in which person can be aroused only briefly and with very strong repeated stimuli

Question 3

Reticular Activating System

Answer 3

Runs from reticular formation in brainstem to diffuse thalamocortical projections to control level of excitability in cerebral cortex by delivering EPSPs. Afferent input (like medial lemniscus) stimulates it

Question 4

Primary vs. Secondary Response

Answer 4

First, from somatosensory specific projection systems vs. second from reticular formation and diffuse projection systems

Question 5

Blocking Primary and Secondary Responses

Answer 5

Only by lesioning specific projection nuclei of thalamus vs. anesthesia

Question 6

Barbituates

Answer 6

Anesthetic agents that make IPSPs longer and EPSPs shorter

Question 7

Synchronous vs. Asynchronous Brain Waves

Answer 7

When not thinking or w/e, dendrites just run at rate of RAS so brain waves are larger. When are thinking, neurons firing at different rates so they cancel out and brain waves smaller

Question 8

Alpha and Beta Rhythms

Answer 8

8-13 Hz, larger rhythm when awake but eyes closed vs. when eyes open or thinking about problem

Question 9

Brain Waves of Sleep

Answer 9

REM is in alpha or beta, deep sleep is in Delta (largest jumps, most disconnected from RAS)

Question 10

3 Kinds of Epilepsy

Answer 10

Tonic-Clonic Seizures: overactivity of RAS causing everything to go off
Absence Seizures: maybe overactivity of inhibitory circuits causing blackout for few seconds
Focal Epilepsy: from injury to one side of brain, spreads waves of excitability and contracts contralateral muscles

Question 11

Sleep Progression

Answer 11

Go from N1/N2 to N3/N4 (light to deep sleep), then return back through to N1 where you go to REM sleep

Question 12

Sleep Spindles

Answer 12

Bursts of alpha rhythm activity in N2 that might be bursts of RAS or to inhibit it?

Question 13

3 Functions of Sleep

Answer 13

Memory consolidation
Reduce dominant circuits to maintain stability
Work underused circuits so they aren’t lost

Question 14

Suprachiasmatic nucleus (SCN)

Answer 14

Pacemaker for circadian rhythm

Question 15

Persistent Vegetative State

Answer 15

Higher cortical centers are nonfunctional, but brain stem still is so reticular formation keeps them in states of arousal and sleep

Question 16

Difference between Coma and Persistent Vegetative State

Answer 16

Sleep/wake cycles