1. CNS system Forebrain Midbrain Hidbrain Part II
Supplemental instruction
CNS system
Part II
Forebrain
Midbrain
Hidbrain
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Developmental categorization of CNS system.
-Forebrain ~ telencephalon ~ forming hemispheres of cerebrum.
diencephalon ~
-Midbrain ~ does not subdivide.
-Hindbrain ~ metencephalon ~ pons, cerebellum
myelencephalon ~ Medulla oblongata, RAS
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Forebrain
comprised of cerebrum and diencephalon
-Involved in emotion, learning and memory
____________
-Regulate sensory info and motor response.
-Basal nuclei in deep region.
Cerebrum
Diencephalon
____________
-Thalamus/epithalamus
-Hypothalamus
-Pituitary gland
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Diencephalon (in forebrain)
-Thalamus/epithalamus(pineal gland)
-Hypothalamus
-Pituitary gland
_________
- relay center to cerebrum
all sensory information except smell
__________
- includes pineal gland which secrets melatonin.
Thalamus
epithalamus
Hypothalamus
_____________
- integrates nervous and endocrine systems
- Regulates anterior and posterior pituitary glands.
- Hunger and thirst, body temperature, emotions
coordinate autonomic and endocrine responses.
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Pineal gland
SCN (suprachiasmatic nucleus)
-regulate ______________(biological clock)
Adjusted daily by light from eyes.
Controls pineal gland secretion of __________ to regulate circadian rhythms
Circadian rhythms
melatonin
*Melatonin is involved in aligning physiology with sleep/wake cycle and seasons.
-Secreted at night
-Inhibited by light
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Choose Thalamus, Hypothalamus, Epithalamus
________
-relay center to cerebrum all sensory information except smell alertness.
-Role in level of arousal.
Thalamus
____________
-integrates nervous and endocrine systems(hormone).
-contains neural centers for hunger, thirst, body temperature.
Hypothalalmus
___________
contains choroid plexus and pineal gland.
____________ secretes CSF.
____________ secretes melatonin
*Melatonin: involved in sleep cycle and seasonal reproduction.
Epithalamus
choroid plexus
pineal gland
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Midbrain
-visual and auditory reflexes
-connects with cerebrum and cerebellum; motor reflexes
- Superior colliculi, Inferior colliculi, Red nucleus , substantia nigra
______________ - involved in visual reflexes
______________- relay auditory information
_______________________- involved in motor coordination
Superior colliculi
Inferior colliculi
Red nucleus and substantia nigra
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Dopaminergic pathways
Neural pathways in the brain which transmit the neurotransmitter __________.
Motor coordination
dopamine
Mesolimbic dopamine pathway
- involved in reward and drug addiction.
- Abused drugs cause dopamine release from the nucleus accumbens.
*heroin and morphine- production
cocaine and amphetamines- inhibit reuptake
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Nigrostiatal dopamine pathway
- Motor control pathway
Dopamine neurons in ______________ degenerate in Parkinson’s disease.
Substantia nigra
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Hindbrain
A: B: C:
pons
Medullar oblongata
Celebellum
Contains______, _________,and _______
pons
cerebellum
medulla
__________ motor coordination; motor learning; trained voluntary activity
cerebellum A
__________ ataxia caused by damage to this area.
cerebellum B C
Ataxia: Loss of the ability to coordinate muscular movement.
__________ Includes two important respiratory control centers
pons
Medullar oblongata
________________ several crucial centers for breathing and cardiovascular systems.
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Hindbrain
___________________________
- an ascending arousal system.
- composed of several neuronal circuits connecting the brainstem to the cortex.
* Textbook says “…originates in groups of neurons in the pons, midbrain reticular formation, hypothalamus and basal forebrain.”
- promotes wakefulness, but inhibits sleep.
- Regulating Sleep-Wake Transitions
Reticular Activating System (RAS)
-Stimulation in RAS causes wakefulness.
-Damage to RAS causes coma.
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Disorder in RAS
Loss of general sense of consciousness or wakefulness.
result in alterations of sleep-wake cycles and disturbances in arousal.
Narcolepsy:excessive daytime sleepiness
Coma
* Be careful!
RAS ~ Promotes wakefulness and inhibits sleep at the day time!
Melatonin in pineal gland ~ Promotes sleep at the night!
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