brain and behavior sleep and dream
how might sleep improve memory
"playback" of info synchronized brain activity may promote storage resetting synapses- scaling "most active" remain stronger
suprachiasmatic nucleus (SCN)
'master clock'
narcolepsy
A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times. loss of orexin neurons in human brain tissue
REM sleep
EEG dysynchrony (rapid irregular waves) muscular atonia rapid eye movements penile erection or vaginal secretion dreams
SWS (slow wave sleep)
EEG synchrony (slow waves) moderate muscle tonus slow or absent eye movement vague thoughts
what activity increases during REM
activity in the pons and limbic system and parietal and temporal
what role does acetylcholine play in sleep
arousal
Which of the following is TRUE concerning the duration of a self-generated sleep/activity cycle (aka 24h internal clock)? a) It is longer if the organism is normally active in the dark. b) It is highly consistent in a given individual in a given environment. c) Every species has a different length of their internal clock depending on their environment
b) It is highly consistent in a given individual in a given environment.
clinico-anatomincal hypothesis
dreams similar to thinking (under usual circumstances) arousing stimuli in the brain are combined with recent memories and sensory info
what role does GABA play in sleep
high during short wave sleep phase inhibits brain activity, makes us tired
what type of memory does SWS sleep help
hippocampus-dependent memory declarative memory- facts and events
what type of memory does REM sleep help
hippocampus-independent memory procedural memory; emotional memories
Histamine
important for arousal released during times of wakefulness
adenosine
important for inducing sleep produced as a by-product of energy production; builds up
circadian rhythm
include behavioral and physiological rhythms
What is the principal zeitgeber for land animals?
light
A proprioceptor is sensitive to the ____.
position and movement of a part of the body
brain activity during dreaming
prefrontal cortex is suppressed (why dreams are inherent) activity is high in the inferior part of parietal cortex; visual-spatial perception activity is high in the hypothalamus and amygdala; emotional and motivational content of dreams
orexin
released by hypothalamus a peptide neurotransmitter, stabilizes wakefulness activates basal forebrain acetylcholine areas, brainstem arousal areas, and cortex stress facilitates release feeding inhibits orexin release
Suppose you fell into a cave and lost your watch. Without any time cues, your circadian rhythm would ____.
remain relatively constant
what are the functions of sleep
repair and restoration energy conservation learning and memory
retinohypothalamic tract
resets SCN based on light input made of special ganglion cells containing melanopsin
zeitgeber
the stimuli that resets the circadian rhythm
activation-synthesis theory
theory of dreaming spontaneous activity of pons activates cortical areas cortex synthesizes a story from pattern of activation
what activity decreases during REM
visual cortex, motor cortex, and the dorsolateral prefrontal cortex
What experience is similar to losing proprioception?
walking on a leg that has "fallen asleep"
Which activity is an example of a motor program in a human?
yawning
The proteins PER and TIM, originally discovered in insect but now found in mammals also, influence circadian rhythms by ____.
building up during the day and declining during sleep