Sleep and Wakefullness Flashcards
what are the consequences of sleep deprivation?
weight loss, impaired cognitive abilities, death
sleep may be needed to replenish __ stores in the brain
glycogen
sleep may be required for ___ consolidation
memory
sleep is intrinsically regulated by ___
internal clock (circadian rhythms)
sleep is extrinsically regulated by ___
light and dark cycle
neurons require a lot of glucose during wakefulness, this glucose is provided by ___ cells
glia;
sleep allows for the clearing of ___ made by neurons
waste (o2 radicles)
t/f cellular repair happens better during sleep
true
t/f sleep is subject to regulation on multiple layers
true
light activates ___ that project into brain structures that house the internal clock
retinal ganglia
the body and brain can regenerate in what stage of sleep?
non rem
heart rate and respiratory rate ___ in NREM
decrease
NREM sleep is longer and deeper at what point in the night?
early
REM sleep is also called __ sleep
paradoxical
REM sleep is characterized by
rapid eye movements, but inactivation of skeletal muscle
heart rate and respiratory rate ___ in REM sleep
increase
REM sleep is longer and more frequent at what point in the night?
later in sleep phase
dreams occur in what stage of sleep?
REM
memory consolidation occurs in what stage of sleep?
REM
t/f it is suggested that REM sleep may have some metabolic demand
true
electroencephalogram EEG allows measurement of
neuronal activity (mainly of the cortex)
what does an EEG look like during wakefulness?
high frequency low amplitude waves
with low amplitude, high frequency waves, what can be said about the neurons of the cortex?
asynchronous , everyone doing their own function
what rhythm is seem in attentive wakefulness?
beta (>13 Hz)
what rhythm is seen in inattentive wakefulness?
alpha (8-13 Hz)
what does an EEG look like for NREM sleep?
low-frequency, high amplitude waves
low-frequency, high amplitude waves suggest what of the neurons in the cortex?
synchronous
the wave frequency of NREM sleep gets substantially slower during what stages of sleep?
2-4
what does an EEG look like form REM sleep?
high-frequency, low amplitude waves (similar to awake)
pharmacological action of benzodiazepines
potentiate actions of GABA and promote sleep
pharmacological action of nonbenzodiazepines
potentiate actions of GABA and promote sleep
pharmacological action of antihistamines
block histamines, promote drowsiness
pharmacological action of antidepressants
inhibit reupatke / breakdown of monoamines, suppress REM
pharmacological action of methylphenidate
inhibit reuptake of NE, cause attention (used to treat ADHD)
in response to external stimuli, the limbic system generates __ and __
goal-directed behaviour and emotions
goal-directed behaviours are reinforced by ___ and diminished by __
rewards; aversive stimuli
goal-directed behaviour subserves both __ and __
primary needs and acquired desires
what are emotions?
outwards expressions, autonomic and hormonal responses
structure of the amygdala
2 almond shaped structures of nuclei found deep within the temporal lobes
the amygdala gets sensory input and initiates ___ behaviour
fear-related
what is fear conditioning?
association of initially neutral stimuli with some adverse stimuli
what structure stores memories associated with fear conditioning?
amygdala
the hypothalamus initiates changes in tone of the ANS, leading to changes is ___, ___ etc
heart rate, respiratory
the ___ elicits changes in hormonal secretions
hypothalamus
the ___ elicits somatic motor responses generating outward expression of emotion
hypothalamus
the ___ is the output region of the limbic system
hypothalamus
the mesolimbic dopaminergic pathway is part of the __ system
limbic
what is the function of the mesolimbic dopaminergic pathway?
generation of pleasure and reward-oriented behaviour
outline the mechanism of the mesolimbic dopaminergic pathway
the ventral basal nuclei is de-repressed through inout from the hippocampus and amygdala and facilitated by activity of dopaminergic neurons in the ventral segmental area of the brainstem, resulting in rewarding effect
what is the function of the ventral basal nuclei?
normally represses initiation of goal-oriented behaviour
the release of dopamine when completing goal-directed behaviour can be beneficial, but can also result in __
addiction
psychoactive drugs are typically structurally related to ___
dopamine
psychoactive drugs result in the increase activation of __
ventral striatum
frequent use of psychoactive drugs can cause:
addiction, drug tolerance, psychological and physical dependence
t/f even psychoactive substances structurally unleaded to dopamine (cocaine, opiates, alcohol) can act by enhancing the dopaminergic activation of the ventral striatum
true
unipolar depression / major depressive disorder
pervasive low mood, lose interest, withdrawal from social situations
what % of men and women suffer from MDD?
10-25% of women and 5-10% of men
bipolar spectrum disorder / manic depression
alternating episodes of mania and MDD
what are the proposed causes of mood disorders?
- combination genetic and social factors
- altered blood flow and neuronal activity in limbic cortex and amygdala
- monoamine theory of depression
what is the monoamine theory of depression?
cause of depression is lack of serotonin, NE and dopamine
list 3 treatments for mood disorders
- monoamine oxidase inhibitors (block breakdown of serotonin, NE and dopamine)
- tricyclic antidepressants (block reuptake of serotonin and NE)
- selective serotonin re-uptake inhibitors
t/f SSRIs are typically very effective for MDD
true
there are more than __ gene variants linked to depression
100
