Sleep Flashcards
EEG records very small electrical fields generated by syanaptic currents in cortical ______
EEG records very small electrical fields generated by syanaptic currents in cortical pyramidal cells
describe what is seen in the EEG
- cortical activity causes high (voltage) amplitude EEG waves; found in the sleeping brain
describe what is seen in the EEG
- cortical activity causes low (voltage) amplitdue EEG waves; normal awake brain
seen in a comatose/unconscious person
describe this hypnogram
describe sleep pressure
- homeostatic process that keeps track of how long we have been awake
- the longer we are awake, the greater the build-up of sleep pressure, possibly reflected by adenosine levels
- sleep pressure interacts with the circadian sleep rhythm
describe the sleep pressure graph
contrast arousal vs sleep systems
- arousal systems (cholinergic and monoaminergic pathways) and sleep-promoting systems (GABA-ergic pathways) are mutually inhibited by turning off each other’s circuitry
- the circuitry that governs sleep/wake cycling is analogous to a flip-flop electrical switch with either an ON state or OFF state
- the switch is controlled by GABA containing neurons in the ventrolateral preoptic region (VLPO) of the ant. hypothalamus that turn off arousal systems in the asecnding reticular activating system (ARAS)
describe the components involved in the ARAS (ascending reticular activating system)
- PPT: pedunculopontine nuclei = cholinergic
- LDT: laterodorsal tegmental nuclei = cholinergic
- RN: raphe nuclei = serotonin
- LC: locus ceruleus = norepi
- VT: ventral tegmentum = dopamine
describe the hypothalamic components involved in wakefulness
- hypothalamus
- LH: lateral hypothalamus
- TMN: tuberomammillary bodies
describe the basal forebrain components involved in wakefulness
- basal forebrain
- septal nuclei
- nucleus basalis
describe the components of the brain involved in sleep
- hypothalamus
- VLPO: ventrolateral preoptic region
- GABA-ergic that inhibits wakefulness
- VLPO: ventrolateral preoptic region
the ____ promotes ____ and ____ during the wake period
____ projections to the ____ influence the firing patterns of sensory relay neurons
the cholinergic system (ACH) promotes thalamic and cortical during the wake period
ACH projections to the thalamus influence the firing patterns of sensory relay neurons
the ____ contains sensory relay stations whare are in “_____” during waking state but go into “____” during slow wave sleep (SWS)
the thalamus contains sensory relay stations whare are in “transmission mode” during waking state but go into “burst mode” during slow wave sleep (SWS)
describe the activity of these thalamic neurons and in what state they are found
how does the suprachiamastic nucleus influence sleep?
- the SCN has minimal projections to the VLPO
- SCN strongly innervates the subparaventricular zone (SPZ) of the hypothalamus and the dorsomedial hypothalamic nuclei (DMH)
- DMH integrates feeding, temp. and light cues from SPZ and SCN
- DMH has GABAergic projections to the VLPO and excitatory projections to the LH
there is transient ____ activation during REM sleep
there is transient cholinergic cell activation during REM sleep
compared to SWS, REM involves increased _____ in:
compared to SWS, REM involves increased blood flow in:
- pons, midbrain, basal gang
- paralimbic regions
- association cortices
____ activity higher in ____ than in awake brain
paralimbic activity higher in REM than in awake brain
describe why there is paralysis during REM sleep
- glycinergic ventromedial medulla nerons inhibit spinal motor neurons during REM-associated motor atonia
summarize the sleep stages
describe memory and sleep
- memory encoding takes place during the waking state, whereas memory consolidation is facilitated during the sleeping state due to the lack of interference from incoming sensory stimuli
