Transcript Slide 1

Brain Tidbit II: Brainstem
• Medulla oblongata
• Pons
• Mesencephalon (midbrain)
Human Anatomy and Physiology I, Frolich, Brainstem
What is brainstem?
• Interior inferior “core” of
brain
• Includes all parts of brain
except:
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Cerebral hemispheres
Cerebellum
Diencephalon
(remember “2-oval skull”)
• Think direct autonomic
control
Human Anatomy and Physiology I, Frolich, Brainstem
Cerebral
hemispheres
Cerebellum
“2-oval skull”
(brainstem deep and inferior)
Medulla oblongata
(relay from the spinal cord)
What is it?
What it does?
• Extension of spinal cord
into cranial cavity
• All motor and sensory
information to and from
peripheral nerves via
spinal cord passes
through
• Central canal of spinal
cord opens into fourth
ventricle
• Autonomic nuclei control
visceral activity
Human Anatomy and Physiology I, Frolich, Brainstem
– Cardio-vascular: heart
rate, strength of heart
contractions, vasomotor
(blood vessel opening)
• Respiratory rhythmicity
center
• Nuclei for Cranial Nerves
VIII-XII
• Relay for sensory and
motor information to other
brain regions
Human Anatomy and Physiology I, Frolich, Brainstem
Pons (relay from “lower” to “higher” functions)
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Links higher to lower brain region
Nuclei for Cranial Nerves V-VIII
Nuclei that control respiration
Part of “metencephalon”
Human Anatomy and Physiology I, Frolich, Brainstem
Midbrain/Mesencephalon
(integration of information for reflexive movements)
• Superior to pons
• Deep within brain
• Superior and inferior colliculi—initiate
reflexive responses to visual and auditory
input
• Substantia nigra and red nuclei (basal
ganglia)—background skeletal muscle tone
• Nuclei for Cranial Nerves III, IV
Human Anatomy and Physiology I, Frolich, Brainstem
Human Anatomy and Physiology I, Frolich, Brainstem
Interactive overview of basic
regions of brain from PBS
[link]
Human Anatomy and Physiology I, Frolich, Brainstem