Sleep Flashcards
reticular formation
The Reticular Formation is the oldest part of the brain.
It forms a diffuse, multisynaptic, net-like meshwork
(reticulum) of widely interconnected neurons in the
Tegmentum
monamine centers
locus ceruleus- NE
substantia niagra and Ventral tegmentum nu- dopamine
raphe nu.- serotonin
RF influences all acsending pathways T/F
T
RF has a key role in this mechanism or theory ?
Gate
Retcicular Activating system
ignition system of the brain
Two Mechanism that excite and facilitate the RAS:
Two Mechanism that excite and facilitate the RAS: Sensory pathways Cortex itself (bi-directional connections between cortex and thalamus).
RAS helps mediate transitions from
RAS helps mediate transitions from relaxed wakefulness to periods of high attention.
The primary sleep/wake oscillators are ?
The primary sleep/wake oscillators: temperature, light
(SCN) ?
The Suprachiasmatic nucleus (SCN) contains a biological clock that governs some circadian rhythms.
SCN projects, via multiple synapses, which are ?
SCN projects, via multiple synapses, to the Locus Coeruleus (LC), and the Ventro-Lateral Pre-Optic (VLPO) area of the hypothalamus: two critical structures for sleep-wake regulation
sleep is defined by what behavioral activities
reduced motor activity,
decreased response to stimulation
stereotypic postures (in humans, for example, lying down with eyes closed)
Relatively easy reversibility (distinguishing it from coma, hibernation).
2 states of sleep
Non-rapid eye movement (NREM) sleep
A relatively inactive yet actively regulating brain in a movable body
→Rapid eye movement (REM) sleep A highly activated brain in a paralyzed body
Importance of sleep
restitution of of brain function and autonomous function, energy saving, and brain growth
stage 1 NREM
Transition from alpha to theta waves on EEG
Is a light sleep, easily responsive to sounds
Typically lasts from 1 to 7 minutes
Hypnic Myoclonus may occur
eyes make slow rolling movements
Hypnic myoclonus
jerking in sleep
stage 2 of NREM
Sleep Spindles and K complexes
Bodily movements continue
Lasts usually 10-25 minutes during first cycle
Constitutes 45-55% of sleep
Probably initiates 0.5 F temperature reduction through the Hypothalamus
Eye movements almost stop
Stage 3 of NREM
As delta waves first appear , sleep spindles and K complex occur, but are less common compare to stage II.
Lasts 10 minutes during the first cycle
Represents only 7% of the total night sleep.
stable vital signs
little movement
sleep walking & talking in humans
enuresis
Enuresis
bed wetting
stage 4 of NREM
High voltage Delta waves now predominate in EEG
Breathing, her rate, blood pressure and temperature are all reduced under the influence of parasympathetic nervous system
Psychologically probably the stage that tells a person he has slept.
Sleep walking (somnambulism)
Night terrors
Skeletal muscles still active!
HALLUCINATION VS DREAMS
Auditory > Visual Not volitionally guided Interferes with the stream of thought VS Usually during REM sleep Visual > Auditory “Lucid” Dreams can be thematically guided
coma
fails to respond to a strong stimulus from disruption of RAS pathways (thalamic or hypothalamic to cortex) or from bilateral impairment of the cortex
